Getting Good Harp Mic Tone

Getting the Best Tone from your Rig

Many people first starting out with amplified harp may think that great tone comes from a super harp mic, or a combination of the mic and amp. Well this is a very misleading belief. The tone you get from your rig is influenced by many things from your playing ability and technique, right down to the tubes and components used in your amplifier. The microphone you use does have an affect on tone, but it’s probably in the neighborhood of 25% influence on your final tone. Choosing the right mic is important, and it needs to be designed and built the way it was meant to be built or it will not perform as well as it can or should. If you have a mic built for you, make sure you get it from a reputable mic builder who knows how they work and builds top quality microphones. Just because you pay someone $250 for a mic doesn’t mean they know what they’re doing. Many mics you see on auction sites with flashy paint jobs were built by painters, not mic builders, so be careful where you get your mic from and ask around for references. You’ll likely hear the same few names come up time after time. Also, look for mic builders who guarantee their work, as I mentioned in the “Building Mic’s” section.

Choosing the Right Mic

Picking the right mic is very important to get the tone you want to achieve. Picking the right mic shell is important too, to get the most out of it. Keep in mind that the size, shape and the material that your shell is made of, will have some affect on the way any given element will sound. Generally, the bullet shaped shells, or shells having a bit of space behind the element seem to have the best affect for good tone from a harp mic element. The shallow shells, like the Astatic biscuit, seem to have an affect that makes the elements sound a bit thinner, but it may not be very noticeable to most people. So don’t choose a shell based solely on this! It’s much more important to be able to hold the mic comfortably, and to be able to use the different hand techniques with it.

Plastic and wood shells may be cool looking, but plastic and wood does nothing to shield an element which helps to keep feedback down, which is a common problem with many of the high output mic’s. I have found that the bullet shells that I have had chrome plated have better shielding qualities than the same type of shell without the chrome, and allow me to be able to turn my amp up a notch higher and getting a little more bite out of the element. Chroming die cast shells usually has to be done in a way different than chroming steel. Being mostly die cast zinc, the shells must first be copper plated, then nickel plated, and then chrome plated. So quite a bit of metal has been added to the shell which is why they have better shielding qualities than painted shells of the same type. Many players don’t like chrome because they do get slippery in sweaty hands, so keep that in mind if you think you might like a chrome plated mic.

Choose a shell that you can hold comfortably, and one that you can hold with your harp in hand, and be able to form a chamber with the palms of your hands around the mic and harp. This technique takes a lot of practice but is probably the single most important technique to perfect. You’ll need to be able to make this chamber with your harp and mic in hand as airtight as you possibly can. Therefore, choosing the right shell for your mic is as important as choosing the right element to get the tone you want from it. Players with fairly large hands find it easy to get used to the full sized bullet mics such as the 520 green bullet, or other shells of this size, but many players, especially the younger, and female players with small hands find it difficult to hold the larger mics comfortably, and be able to get a good seal around the mic and harp with their little hands. Therefore, players who can’t handle the larger mics should choose one of the smaller shells usually available from most good mic builders. There are many types and shapes of mic shells out there, so finding one to suit your needs shouldn’t be a problem.

Various Models of the JT30 Shell

Many players love the Astatic JT30 shells which are slightly smaller in diameter than the Shure 520’s, and like the old art deco look of them as well. These shells were made starting back in the late 30’s I believe, so there are plenty of them around and are easily found on most auction sites. This type of shell was also used for other model number mics, other than the JT30 in the early years. Some of the models I’ve seen using this type shell had tags on them with the following model numbers stamped on them: A, 30, 40, A30, W30, W80, JT30, JT30VC, JT31, JT40, and probably a few others that I don’t know of.

This same type of shell was offered by CAD, a subsidiary of the Astatic Corp. which made the same mic called a model HM50, or HM50VC, the VC meaning the mic came with a volume control. The CAD mics are just JT30’s with a brass plated (gold colored) grille and a flat black body rather than the usual chrome grilles found on the JT30’s. The Hohner Blues Blaster, which I believe is still in production today, are still using these shells. Recently the grilles have been changed slightly and don’t have the same detail that the vintage JT30 chrome grilles had, but they do fit the vintage shells.

So as you can see, the ever popular JT30 shell was used on many different mic model’s, most of them being vintage model numbers dating back into the 40’s and 50’s before they were just called JT30’s. The JT30 is a crystal mic, but the shell is able to house just about any mic element you choose without much modification if any at all. The older models are slightly shorter than the later models, as are the Canadian models which I prefer over the longer ones. They’re not much shorter, but they are, slightly. The newer models have a more rounded end, whereas the shorter models have more of a pointed end of the shell body.

The Astatic “Biscuit” & the EV 605

Another of the smaller shells is another shell made by the Astatic Co. It too carried the model 30 on some of them but many had no visible model # or tag on them. This shell is better known as “the biscuit”, which is a small round mic that came on a stand, usually found as an accessory to old console units made in the late 30’s and early 40’s by other mfg’s, that had recording capabilities. These were crystal mics that are either all brown, or brown with a chrome grille, and were about 2 1/4 inches in diameter with a very shallow body that has a hump on the back, and a domed grille. The crystal elements are usually long gone these days but you can find the shells around in very good condition. These are probably the smallest and easiest mic shells to hold for those who have trouble with the larger shells. These shells will also hold just about any element you choose, but may require a custom gasket. These shells are popular with many players, even those who can handle the larger shells. The only real drawback with this type of shell, is that it is almost impossible to use with a built in volume control due to it’s small size.

Another shell made by Astatic is the model T3 which is an all chrome shell that is slightly smaller in diameter than a 520 and has a metal mesh, dome shaped grille, but it quite comfortable and easy to hold. It has a long stem built onto it that is meant to be used with a mic stand which can be bothersome to some people, but it can be cut short and customized to make it less cumbersome. The head of the mic moves back and forth on a swivel that is built into the stem and the shell. As I mentioned, this stem can be cut up close to the mic and a screw on connector installed on the shortened stem making it adjustable as to where you want the connector to be while using the mic. Because the swivel is built into the shell, you really can’t remove it completely. It is possible, but you will be left with a good sized open slot on the bottom of the shell. You can see an example of this in the picture section.

Another small shell very popular with harp players is the Electro-Voice model 605. It is a small, all polished metal shell that has a narrow diameter, maybe 1.25 inches or so, and has a streamlined body that is very easy to hold. These were originally dynamic mics that came in high and low impedance models, and make for good harp mics as all original, but these shells will also accept just about any element you wish to put in it, but are a bit more difficult to customize to use other types of elements if done properly. I’ve seen these types of shells with CM’s in them with the element resting on top of a wad of polyester pillow stuffing, and a half a roll of tape wound around the element to hold it in place. This is not the way you want your mic built. It won’t respond the way it should and just won’t work anywhere near as well as it could if built properly. Its things like this that make it important to have your mic built by a reputable mic builder.

The Smaller Shure Bullet Shells

Many players really like the old Shure crystal mic shells made in the 40’s, which have a slightly smaller diameter than the regular 520’s.They are roughly 1/8 of an inch smaller in diameter than a full sized 520. These slightly smaller shells were used only for the older 707A’s and some of the older bullet mic models used in the early to late 40’s. These shells are quite popular with many players but are not as easily found, and usually sell for a good buck on auction sites. Finding them in near mint original condition is very rare, but there are some out there. Be prepared to pay top dollar for mint condition mics, and don’t expect them to work well enough to gig with if you do find one in working condition. You can occasionally find them in working condition, but 99% of them are too weak to be usable, and they will be extremely fragile if they do work, so if you do find one, you might want to put it on your desk or mantle and just admire it if you want it to keep its value! If you buy one for its size, you’re better off buying a beat up one and refinishing it yourself

Other Shells

There are many home brew mic shells popping up all the time in all kinds of shapes and sizes. The trick is to find the shell that you can handle the best, and one that you can hold comfortably while forming as airtight a chamber as you can around it with a harp in your hands. The better you can seal the chamber up, the better your mic will sound and the more you’ll be able to alter the way the mic sounds with your hands. So, once you’ve found the right shell, choose the element that will give you the tone you like best, and have a reputable mic builder put it together for you properly to get the most out of it. Once you’ve got the mic-shell combination that’s best for you, work on perfecting your technique handling the mic and harp while playing. You will find that you will be able to get a whole bunch of different sounds from the same mic by using your hands as sound deflectors, mufflers, fluttering and chamber forming.

Choosing An Amp

As with microphones, there is a whole world of good amps out there to choose from that will give you a good harp tone. Beginners will probably want to start off with a small practice amp to use to develop your technique. Your technique will be one of the biggest influences on the final tone you hear coming out of your amp, so don’t expect to sound like William Clarke or Sonny Boy once you get a good mic and amp! As you’ll probably notice sooner or later, any great harp player can make just about any rig sound great no matter what it is.

Point to Point vs. PC Board

I’d like to first comment on an amp subject that seems to have many different opinions from many people. The subject of “point to point circuit’s vs. a printed circuit board”. I have discussed this with many people and technicians, and everyone seems to have a different theory. First, a PCB (printed circuit board) is just a board full of holes for all the perspective parts, with a thin copper trace going from one point to another to complete the connection from one hole to another. As long as the parts are inserted and soldered in properly, the circuit works just as well as the same circuit on a turret or eyelet board.

A true point to point amp is rarely seen these days. They are very time consuming to build and also expensive to build. A true point to point amp does not use a turret board, or an eyelet board. A true point to point circuit uses insulated stand off’s for each and every point of contact, and all the parts are assembled to these stand offs in an actual point to point contact manner. These amps usually look like a rats nest when completed because they are difficult to build neatly. Most of the custom made amps you see today use eyelet cards, or boards, or turret boards which do the same thing in a different way. The turret lugs are stand off’s, instead of eyelet’s, in which parts are soldered to, and eyelet boards use eyelets to connect the parts together. The advantage of eyelet and turret boards is more of an ease to work on advantage rather than any electrical or tonal advantages. They are also more rugged and less prone to bad connections and cold solder joints. The materials used to make the boards these days are much better than the fiberboard used years ago. Today’s phenolic board materials are much stiffer, and won’t bend out of shape when you fill them with parts like the fiberboard will. The phenolic material also does not absorb moisture as it’s said that the old fiberboard would. This could be a problem with noise if used in a high humidity climate. But it’s been my experience that as far as having tonal superiority over printed circuit board, I really don’t think so as long as the same components are used. One of the down sides of PCB’s, is that they can be difficult to work with, especially when removing parts who’s leads have been bent over the solder hole. Solder eyelets and the traces can be easily damaged when removing hard to get at parts, especially when you don’t have the proper specialty tools to work on them, but I really don’t think that PCB’s are inferior to other types of turret and eyelet boards sonically. They’re simply much easier to work on when it comes to diagnosing and replacing parts.

Outside of reliability, think the PCB’s are just as good sonically as turret and eyelet boards. One thing that can affect the way a circuit performs and sounds is the layout, or physical design of the circuit board. Where certain parts are located, and their proximity to other components can affect the way a circuit performs. Sometimes PCB’s will have a whole bunch of components crammed together closely on a small board to accommodate limited space in which to work with. Situations like this may be the reason that some PCB amps don’t sound as good as the same circuit laid out on an eyelet board amp.

Popular Tube Amps

The most popular amps with most harp players are the amps that are all tube driven. Solid state amps just don’t have the same tone that tube amps have, and although there are a few decent solid state amps that have good harp tone, almost all amps used by harmonica players are either vintage or boutique all tube amps. Some of the more popular smaller amps being used today are the Fender Pro Jr., the Champ and Vibro Champ, the Blues Jr., and the Princeton, which is more of a medium sized amp. Also popular are some of the older smaller Gibson’s, and the old Sears & Roebucks Silvertone amps that usually have a single 8, 10 or 12 inch speaker and have a power output of around 8 to 15 watts. This is usually plenty of power to drive your family members out the door, but not enough to gig with or annoy the neighbors. There are a number of other amp mfg’s who made small 8 to15 watt tube amps that sound pretty good as well as the ones mentioned.

There are many medium sized amps around to choose from. Again, the all tube amps are the front runners for best tone. The Fender Princeton is a very popular medium sized amp, as well as the Fender twin and the Gibson GA30, and a couple of the Silvertone models which I’m not familiar with, but these vintage amps are usually not cheap. If you’re looking for something with decent tone but won’t put you in debt, look for the smaller Silvertone’s, and the less popular name brands. There are a lot of home brew amps around that you can get cheap that will give you good tone to start out with, but if you’re looking for an amp that you can gig with that will cover fairly large clubs, you’ll need something around 40 to 50 watts or more.

The 59 Fender Bassman

Without a doubt, the most popular of the larger amps being used by gigging harp players is the Fender 59 Bassman 4X10 amp, or some other 4X10 amp that’s based on the famous Fender 59 Bassman circuit. It’s my favorite too, so I feel compelled to put this section on my site. Just about every amp mfg. has put together an amp based on the Fender 5F6-A bassman circuit. This is a very simple, basic circuit design that Fender made famous for its signature warm clean vintage tone. It was originally designed to be a bass amp as the name suggests, but it turned out to be a great amp for guitar, and especially, harp. It’s my favorite amp without a doubt, and I own two of them and two tweed Blues Jr’s. that I have modified to suit my taste. One bassman is a reissue and the other is an eyelet board amp that I built from scratch using the original 5F6-A circuit and layout (see picture section), although I have modified it extensively. These amps have very high gain, the original tag board circuit amp more so than the reissue. All of my amp’s I have modified for better tone to suit my taste for harp.

The 59 Bassman reissue as it comes out of the box is a decent sounding harp amp, but it can definitely be improved upon. As they used to come with a solid state rectifier, in the form of a solid state plug that fits into the octal tube socket, you can replace it with a tube rectifier, which is the first thing you can do to improve it’s tone. I suggest using a 5U4G or a 5U4GB rectifier to get the most tube sag, and having the fixed bias replaced with an adjustable bias control so that you can adjust the amps bias. This will allow you to use a variety of new and NOS (new old stock) output tubes and have the amp biased to any particular set of tubes.

Those of you who have a 59 Bassman know that plugging a nice strong green bullet into it can cause the amp to squeal like a pig with the volume control on 2. This is because the green bullets and most crystal mics have a very strong output signal, way stronger than a typical guitar would have. The squeal is caused by the high gain of the mic, and the high gain of the preamp tubes. Leaving it like this just causes you to put an overloaded preamp signal into the power section of the amp, and you can’t drive the amps output section into natural distortion, which is where these amps really start sounding good.

One way around this is to change the amps 12AX7 preamp tubes to lower gain tubes. Most of the common preamp tubes all work in the same way, but some have a lower gain factor than others. The gain factor of the preamp tubes determines how much the preamp amplifies the input signal before being sent to the output section of the amp. All preamp tubes have a specified gain factor, with the 12AX7 having the highest gain factor of all the preamp tubes. The Bassman comes equipped with all 3 preamp tubes being 12AX7’s, which is great if you’re going to use it for guitar, but not for use with a mic with high output. Therefore the best thing to do is to lower the amount of amplification in the preamp section by replacing the high gain tubes with lower gain tubes.

Here’s how the preamp tubes are rated for gain. The 12AX7, which is the highest gain tube, has a gain factor of 100. A 12AT7 has a gain factor of 70. A 5751, which is a high quality tube made to be used as a direct replacement for a 12AX7 with lower gain factor, has a gain factor of 60. A 12AY7 has a gain factor of 40, and a 12AU7 has a gain factor of 18. Any of these tubes can be used in any of the preamp positions of the 59 Bassman. Lowering the gain factor of other amps is usually possible, but if you have a different amp and want to try reducing the gain factor of the preamp, you should check with the mfg. or a technician who is capable of giving you correct information. Not all amps can use different types of preamp tubes!

There are also many things that can be done to most amps to give them better harp tone, but unless you understand electronics and what all the different parts do, there’s no sense in me getting into that in detail, but changing the types and values of certain components in your amp can also help you get better tone from your amp. The tubes that I use in my reissue Bassman are, a 12AU7 in the first and second stage of the preamp, (the 2 sockets farthest to the right looking into the back of the amp), and a 5751 in the phase inverter position (closest to the power tubes). I use and recommend that you use Tung Sol, or another US mfg. of 5881 power tubes. They have a warmer tone, and break up sooner than the Russian 5881’s or 6L6’s, and use a 5U4G rectifier tube. New old stock Tung Sol 5881 tubes are usually fairly expensive as compared to others, but well worth the extra money if you want the best tone from your amp. If the Tung Sol’s are too expensive for you, you can use other US made 5881’s with good results. Other than the Tung Sol’s, I like the GE’s best.

Tung Sol made 5881 tubes for other companies like GE, RCA and others, and the tubes are identical other than the name on the tubes. You might be able to find some of these cheaper, but the Tung Sol 5881’s are highly sought after tubes and the people selling them know this, so they usually sell for a pretty good buck. This tube set up allows me to be able to push the output tubes into natural distortion giving the amp a much better tone that is less harsh and much warmer than the stock tubes. I recommend using new old stock US made tubes in the preamp as well, or, if you have the bucks for the expensive European tubes, go for it, but stay away from the Japanese and Chinese tubes. With this tube set up, I can turn the volume of the #1 bright input up to 6 or more depending on the mic I’m using. With the amp that I built, I need to use all three 12AU7’s in the preamp. The original Bassman amp circuit has much more gain than the reissues. With this amp I can get the volume up to near 7, which is where you want to be to push the output tubes into distortion.

These amps sound fantastic with plenty of volume, grit and bite without feedback. I have done other modifications to my amps but these are the first things to do with a stock Fender 59 Bassman reissue. I like the older reissues best. The ones that came with the blue framed Eminence alnico magnet speakers. I think these are one of the best speakers for harp on the market today. Actually, they are no longer being made. The ones that came in the Fenders were special designs, but basically the only difference between those and the Eminence model is the dust cap. The Fenders have a paper dust cap on the speakers giving them a slightly brighter tone. The Eminence models were made with a felt dust cap and are less bright sounding than the Fender design. Either of them make for great harp amp speakers. I believe that Fender is now using Jensen reissue speakers in the current 59 Bassman reissues which are not getting as good reviews as the Eminence speakers did in the older bassman’s from what I’ve heard.

Speaker Selection

Speaker selection is also a very important part of your final tone. Most harp and guitar players believe that the old vintage Jensen speakers have the best tone of just about any speaker out there. They can be difficult to find, and expensive if you do find them. There are also a couple other speaker companies that made superior speakers, even better than the Jensen’s according to some audio buffs, such as Fane and Heppner, but I can’t rightly say that this is true because I have no personal experience with them. However, I have talked to many harp players who do use them who say that they are in fact excellent speakers. I do however have some experience with vintage Jensen’s. I have a 1956 Jensen P12RC Professional Series speaker in my Blues Jr. The speaker alone turned this little 15 watt amp into a tone beast. Not that it’s blowing out windows or rattling the doors, but the tone is better than any other amp of this size that I’ve ever heard. It’s loud enough to gig with if mic’ed, but the tone is of the likes I’ve never heard from any other speaker. I also did some mod’s to it and upgraded the output transformer, but I fully believe that it was the speaker that turned a mediocre amp at best into the best tone I’ve ever heard from a small amp, and it’s a 12 inch speaker too, which aren’t known for being the best size speaker for harp amp’s.

Many people believe that a 12 inch speaker won’t produce a real crunchy tone and prefer the smaller speakers. This is not true! This particular Jensen has a strange dust cap on it that appears to be half paper, and the center is some type of see through brass mesh or something. The cap itself is about the size of a quarter. The label on the speaker magnet housing says, “Specially Designed for Commercial, Industrial, and Institutional Use”. I’ve tried, but have been unable to get any good information about this speaker from anywhere. If you’re a vintage speaker guru who knows about these “Professional Series” Jensen’s, I’d love to hear from you! Whatever it is, it’s got TONE!

Choosing A Speaker

There are a number of good speakers being produced today that make for great harp amp speakers. A few mfg’s do produce speakers specifically to produce good harp tone, or are made to sound like the vintage Jensen’s that have become popular with harp players. These speakers are usually made a certain way with certain materials, such as thin paper cones and alnico magnets, to produce the same sounds of the popular speakers of the past. Your speaker is what produces your final tone, so be sure to find the right one

The right speaker can make, or break the tone that you want to get from your amp. Look through the websites of current speaker mfg’s and find out which ones will best suit your amp. You can usually email or call on the phone to these places for technical support, and maybe get some suggestions. Most places will be happy to help you choose the right speaker. Speaker specs can be confusing, so ask a lot of questions. You’ll need to choose a speaker that first will give you good harp tone. Personally, I like the Eminence Legend Series speakers, which are what I use in my Bassman amps. Many harp players today are giving the Weber speakers good reviews as well.

You’ll need to get a speaker with the correct impedance for your amp too, which is its resistance spec, or its ohm rating. You will need to select a speaker that is of the right power rating for your amp too. If you have a 15 watt amp, you don’t want to choose a speaker that can handle 100 watts. It likely will sound like it’s hardly being driven and sound low in volume. Choose a speaker that can safely handle the amount of power that your amp can produce, but don’t go overboard. Choosing a 20 watt speaker will be plenty for a 10 to 15 watt amp. Keep in mind that a speaker’s efficiency will have a lot to do with the amount of volume it will put out. You may have noticed from past experience that some speakers that have the same power rating as others, will sound louder than the others. Speakers DO NOT produce power, unless they have a built in amplifier, so choosing a 50 watt speaker is not necessarily going to be louder than a 25 watt speaker.

A speaker’s ability to produce a certain amount of loudness as compared to the amount of power being put into the speaker is the speakers efficiency rating, which can be difficult to understand as they put it in the speakers specifications. Loudness is measured in db or, decibels. Unless you know how loud 90db is or 100db is, it will be difficult to understand a speaker’s efficiency rating. Generally, the less amount of power a speaker needs to produce let’s say for example, 90db of sound, the more efficient it will be. One speaker may require 20 watts to produce 90db of sound, whereas another may require only 1 watt to produce the same amount of volume! The loudness is usually given as a decibel rating at a given distance from the speaker, usually 1 meter, with the amount of power that the speaker needs to produce that amount of sound. If you do your homework on this subject, you will see that some speakers are much more efficient than others that have the same power rating, therefore, they will produce more sound or loudness with less power than speakers that are less efficient. So keep in mind that it is a speaker’s efficiency that makes it produce more volume, rather than its power rating.

So, as you can see, getting good tone from your rig has many things affecting what you’re hearing. There are many things you can do to change the tone to make it sound the way you want it to, but there are no magical mics, or amps, or pedals, or anything else out there that are going to give you fantastic tone. It’s a combination of everything in the chain from your lips to the speaker in your amp that affect the way your playing sounds. Once you develop your technique and hone it down, you’ll be able to make just about any mic-amp combination sound great. If you have any questions about how you may be able to improve your mic or amp, feel free to email me by clicking on the email link at the bottom of this page and I’ll do my best to answer your questions.

Harp Specific Amps

As most of you already know, there are quite a few new amp’s being built by various amp builders that are built specifically for harmonica players. Most of these amps have their own very distinctive sound. Some are small 8 to 15 watt models, which are great for practice, or to use in small venues where a larger amp is not necessary, and some are larger 30 watt and higher models meant to be used by the gigging harp players who want an amp that is suitable for most any situation. Many of these amps have great tone, but most of them have their own distinctive tone that cannot be altered very much, and do not appeal to all harp players who like to have the option of changing their sound, say from loud and gritty to loud but clean. Everyone has their own opinion of what good tone is. Some custom amps do come with circuits that have the ability to accomplish this, by adding a switch on the amp that changes the circuit from a clean channel to a more dirty sounding channel. Some custom amps have controls on top of the amp to adjust the tone to do the same. As of yet, there doesn’t seem to be a favorite amp that everyone is using.

Harmonica specific amps are still fairly new, and there are different amps and circuits popping up all the time. This is great for us harp players because harp amps need to be built differently from guitar amps. Most harp amps do not make for very good guitar amps, harp amps need different circuitry. There are only a few really good harp specific amps to choose from these days, but I’m sure that will change in the years to come as more and more people start building amps specifically for harp players. Have you ever noticed that accordian amps make for great harp amps? That’s because accordian’s, like harmonica, have different requirements and don’t need certain things that guitar amps need to produce the amplified sound accurately. As amplified harp becomes more and more popular, more amps will be made, hopefully with the quality of real genuine boutique amps.

One thing that I’ve noticed, and have also heard from others as well, is that so called “boutique” amps are not living up to what they should be. When I hear the term “boutique amp”, what comes to my mind is a custom built, hand made amp, made to the highest standards with the best components available from top to bottom, including a custom cabinet, and usually with a hefty price tag. Maybe I’m missing them somewhere, but many of the so called custom boutique amps being made today seem to have taken on a commercial type of quality, with cheaper parts and standard workmanship. To me a boutique amp should be something special, a one of a kind made to order, and not just something different. I know that there are many very good amps being made by very good amp builders, but it just seems to be that the amps these guys are putting out are good amps, but they don’t live up to the “boutique” standard that used to be. I guess maybe it could be that there just isn’t enough money to be made building amps to that standard because at today’s prices, a real boutique amp would cost $1,400 or maybe more just in parts, and building to such a high standard takes much longer than simply slapping things together quickly. Thus putting a price tag on them of close to $2,500 for a simple amp like a Fender Bassman. I hear the Victoria’s come close to this kind of quality. I’ve never actually seen one, but I have seen the price tags! I’ve heard that some amp builders are charging close to $2,500 for their custom amps that are nowhere near boutique quality. I’d really like to see someone start building harp amps to this standard. My momma used to tell me all the time, “you get what you pay for these days”, which I have found, is true 98% of the time. The other 2% of the time, you get ripped off. It’s about time for someone to start building genuine boutique quality for us harp players! Heck, we’re paying close to boutique prices now!

Modifying Amps For Harp

There are literally hundreds of modification’s that can be done to a bassman reissue, or a bassman tag board (point to point type) clone amp, or any other amp that can be modified for harp. Almost all of these mod’s, including mod’s changing the input resistance to make the amp respond better to a high output, high impedance microphone, have been around for as long as the tube amps themselves.

Modifications of every type imaginable have been tried throughout the years since the first tube amps were developed. Many of the mod’s that do work well for harp, did not work well for use with guitar, and therefore were never used in guitar amps. After all, they were building guitar amps, not harmonica amps! They were not commonly used mod’s and therefore were brushed aside and not documented, or talked about much, if at all, when it came to modifying guitar amps

However, many vintage amp’s that were built for use with accordion, or had an input for accordion, did come with a high resistance input and a lower resistance input for guitar. These amp’s usually sound pretty good with a high Z mic for harp. This is due to the accordion’s need for a different input resistance to sound good, just as a harmonica has different needs in an amp to sound good. Harp amp’s have many other needs to sound good as well, and like guitar amp’s, there will be many different design’s in harp specific amp’s being made by different harp amp builders, as we are already beginning to see.

Harp specific, and harp modified amps are sounding better all the time. There are more and more harp players who are capable of designing and building new amps, and modifying old tube amps with the right mod’s for great harp tone. These are the guy’s who are taking the time needed to experiment with all the different types of components available, and finding the right parts and circuits that work best for harp. This kind of experimenting takes more time and work than you likely can imagine, but I can tell you first hand that it takes literally months, and sometimes years to perfect a harp amp circuit. You really need the determination and the passion for the instrument to put that kind of time and effort into designing the perfect harp amp.

There are really no standard modifications that should be done to an amp for better harp tone. Every amp will have it’s own “personality” for lack of a better term, due to it’s components and specific layout of the components. Other things such as the speaker or speaker’s, the tubes being used, and the microphone all will affect how any given amp will sound, as well as your playing technique and style. If you want to have your amp modified for better harp tone, it should be done by modifying a specific part of the amp’s circuit which would be determined by what you want to accomplish. It should be done and tested with the microphone that you use mostly, and then adjustments made after testing the amp’s tone if more changes are needed.

You should have your amp modified by a tech who is knowledgeable and experienced with making modifications for better harp tone, and not just any good guitar amp specialist. Preferrably, have it done by a tech who plays harp if you can find one. You should also be allowed to play and hear how the amp sounds while the tech is making the modifications if at all possible so you can have the amp tuned to sound the way you want it to sound, and not the way the tech wants it to sound. If this is not possible, and most times it won’t be, let the tech know exactly what it is you don’t like about the way the amp sounds before hand, and exactly how you would like it to sound after the work is done. If your tech plays harp, let him take your mic if you can let it go for a while so he can tune the amp using your mic and not a mic that sounds totally different. If you plan on making any speaker changes, have the new speaker(s) installed before having the amp modified.

It can be very difficult and at times very frustrating trying to find the right design, but the end result is well worth it all. It’s very difficult for a guitar amp tech, or an amp builder who doesn’t play harp, or, who doesn’t work closely with a harp player, to make the right modifications or create a great harp amp. There’s no guessing when it comes to modifying. It takes a lot of time and design changes to develop an amp that will sound good with all the different types of mic’s used, and the sound that the harmonica produces. All amps will react differently to different types of microphones, so it’s not easy to develop an amp that will work great with all types of mic’s. I really don’t think that there will be any one harp amp made that will satisfy everyone’s needs as far as tone. We all have a different opinion of what the perfect tone is. Many players don’t like the distorted tone that many players crave, and many players don’t care for clean tone at all, but both are necessary to satisfy the needs of all harp players.

Designing one amp that will satisfy everyone’s tonal needs for harp will pretty much be impossible, but with all the new amp’s and mod’s becoming available, there should be something available that will satisfy everyone’s needs if they look in the right places. It’s impossible for me to tell you where to look with all the new designs and amp’s becoming available because they’re all coming from different people and places, but searching the internet should lead you to the right person or place to find something that will work for you. I believe that the harp amp business is still in its very early stages. There are more and more harp amp’s popping up of all sizes and new modifications becoming available for new and older amp’s all the time. I believe that as time goes on, we’ll have plenty of options in “harp specific” amps and modifications that will make it much easier for us to find the right amp or mod’s for the amp’s we already have.

One person I can recommend to you for a good harp specific amp is Scott Berbarian, owner, designer, and builder of Meteor Amplifiers. Scott lives near where I live, so I’ve had the chance to visit Scott and see first hand that Scott builds a top quality amp. Scott now has at least two model’s that I know of, the “Meteor” and the “Mini Meat” I believe is the name of a smaller amp that he’s come out with. The Meteor amp is a harp specific amplifier, and because Scott builds them one at a time, and they’re going out the door as fast as he can build them. I haven’t had the chance to play through one myself, but I can tell you that his amp’s are getting great reviews and are being used by some professional’s, Kim Wilson being one of them. That ought to tell you something about the tonal quality of his amps.

Experimenting with the Bassman

As I mentioned before,one amp that seems to be a favorite in one form or another is the Fender 59 Bassman 4X10. This amp has been a favorite of many of the worlds best harmonica players for many years. It has been copied by just about every major amp mfg. in one way or another, but in the form of guitar amps. The 59 Bassman reissue makes for a very good harp amp as it comes out of the box. It has been tested and put up against a few of the more popular custom harp amps of today in a blind “harp amp” tone test. It came out on top as being the best amp for overall harp tone against other amps of similar size, including a couple amps that are harp specific amps. Very many harp players still use the Fender 59 Bassman as their main amp, but many of them have been modified in one way or another, to make it more harp friendly, or to make it sound better using certain favorite mics.

There are countless ways in which to modify these amps for better harp tone, and it seems that everyone who has had one modified, has had something different done to it than everyone else’s modified bassman. There is no question that certain amps sound better with certain microphones, and the 59 Bassman is no different. However, it can be made to sound unbelievably good with just about any microphone, but most players have a favorite mic, and usually will have the amp tuned for that specific mic. The 59 Bassman is without a doubt my favorite amp. I own a reissue made in 1996, and I have a 59 Bassman clone tag board (point to point) amp that I built myself and have modified it to sound it’s best in my opinion, with a very hot Shure vintage controlled reluctance microphone, which I’m sure you know by now is my favorite harp mic. I built this amp a couple years ago and have been modifying it in every way imaginable throughout the course of almost a year. I have tried using all the parts that supposedly supply the magic mojo that certain people claim to be a “must have” to get the ultimate tone. I’ve tried many different types of capacitors, from the high end Auri and Hovland modern caps, to the vintage Sprague orange drops, the new orange drops, and the paper in oil caps. I have tried carbon composition resistors, carbon film resistors, and metal film resistors, as well as wire wound resistors. I have tried using different transformers, different voltages to the amp, and just about every one of the millions of tube combinations that can be used with this amp. I have even tried many different combinations of filtering the power supply, although I only used the Sprague Atom electrolytic caps in the filter sections. It did seem apparent that over filtering the power supply did rob the amp of tonal quality, although it was not hugely noticeable, but none the less noticeable enough to hear. Under filtering will make an amp sound muddy. Many people feel that the original 59 Bassman was under filtered, and use more filtering in the power supply and preamp of the clone amps being built today. The 59 Bassman reissue does have more filtering than the original 5F6-A circuit. The first stage of the power supply went from 40uF to 50uF, the second stage went from 20uF to 23.5uF, the third from 20uF to 22uF and in the 4’th stage to the preamp which went from 8uF to 44uF. So really only the first and last stage saw a significant increase in filtering.

As far as components went, there didn’t seem to be a very noticeable difference from the expensive modern coupling and tone caps as opposed to the cheaper more popular polyester caps such as the Mallory 150 series, CDE, and vintage Sprague orange drop poly caps. However, the new Sprague polystyrene orange drop 715 and 716 series caps did seem to have a slightly brighter tone when I used only those, especially the 716 series. These cap’s have a real tinny sound and I would recommend staying away from the 715 and 716 series Orange drop’s. They do not have the fuller tone characteristics that the older polyester cap’s have.The paper in oil caps did not seem to give the amp any vintage mojo that some people seem to think you must have to get the magic tone. If anything, I thought them to be about the same tonally as the 60’s vintage NOS Sprague Paper-Mylar Orange drop cap’s, which are polyester film caps with a thin foil conductor and epoxy dipped. They’re pretty much the same as the newer Sprague PS series orange drops. I settled on the NOS Sprague orange drop mylar caps, which seemed to have a nice warm tone to them, although I did not like the new orange drop 715 and 716 series caps. The Mallory and CDE caps were about equally as good tonally. So as far as the paper in oil cap mojo thing goes, I don’t buy it! They’re not bad, but there’s certainly no magic mojo in them and I wouldn’t pay any more for them than I would the polyester cap’s.

With resistors, I first tried the carbon film type, which is what Fender equips the reissues with. The amp had a nice warm tone, quiet, with no apparent coloration. Next I tried metal film resistors. Not much of a change in tone at all, maybe slightly brighter if anything but it wasn’t very noticeable. Next I tried the carbon composition type. The tone of the amp seemed to be slightly warmer, but with lots of hiss, pop’s and crackling. Don’t know if I had a few bad ones or what, but it wasn’t worth finding out and replacing them. The tone didn’t change enough to justify keeping resistors in there that are known to be noisy, and prone to drifting with temperature changes. I also decided to try out some so called designer resistors. I tried the Riken Ohm carbon film on ceramic base type resistors, which are said to have the tonal qualities of the old Allen Bradley carbon composition resistors, but having a 1% tolerance and the ability to handle a lot of heat without drift. These are high end Japanese resistors that they claim are used in many top quality Japanese audio components. These resistors are physically exactly the same size as regular carbon comp resistors, but they are blue and have gold plated extra long leads. They all did measure to within the 1% tolerance. They claim to be able to handle any situation so I used one in every spot that needed a resistor. Tonally they did have a nice warm tone, similar to the carbon comps but the amp was dead quiet, even with all controls on 12. It’s very hard to say whether or not resistors really do anything for an amp as far as tone goes. I would say it might be noticeable to a trained ear, but very minimal. It could be the voltage differences from one type to another giving the tonal differences due to resistor tolerances or something of that nature, but the carbon comp resistors definitely introduced an audible hiss that was not present with any of the other types of resistors. The tonal differences were much more noticeable using different types of capacitors than resistors. The Riken resistors stayed in the amp.

Finally, after close to a years worth of trying every mod I could find, I have finally settled on a bunch of mod’s that combined, make the 59 Bassman “modified” circuit a superb harp amp that gives me the tone that I always knew I could get from it with the right type and combination of parts. The amp has excellent volume before feedback, way better than it was as stock, and it has a very strong mid presence with plenty of punch and gritty honk to it. It responds very well to high notes and has plenty of low end. You not only will hear the amp, you can feel it as well. I could never feel the sound and the low end rumbling through the floor like it does now, and it has great tone even at lower volume settings. I also recently have added a “resonance” circuit to the amp, with a control in the spot on the chassis where the ground switch (which isn’t needed) was. This feature lets you have more control over the intensity of the tone. Turn it all the way down to make it sound a little soft, or turn it all the way up for an “in your face” intensity. It took me a long time to get this circuit working the way I wanted it to, but all the hours of experimenting have paid off.

The Fender 59 Bassman amp has always had the ability to be an even better harmonica amp than it is as it comes as stock, and it is a pretty good amp for harp right out of the box. With the right modifications, it can be an awesome harp amp and it can be tuned to specific types of mics for maximum tone and volume before that nasty feedback set in.

Along with building my “Harp Fanatic” amp, I have decided to do some amp modifying services as well, but only for certain amps, the Bassman being one of them. I also have some excellent mods for all you Blues Jr. owners. This little amp can be made into an awesome sounding harp amp. It has not been a very popular amp with harp players because it comes stock with a speaker that is not very efficient and has terrible tone for harp. With the right speaker and some internal changes, the Blues Jr. can become one of the best sounding small harp amps you’ll ever hear. It’s got all the tone control’s, a preamp and master volume control as well as a built in reverb. There is also a “clean boost module” available for it through “Bill M’s Blues Jr. Mods” website which he claims adds 10db of volume boost without affecting the amp’s tone. I have installed one in my Blues Jr., and a couple others and can say that it does increase the volume noticeably. It can be wired in to turn on with the “FAT” switch, or it can be wired to be on at all times which is how I wired it into my amp. One thing the Blues Jr. lacks is volume, and the module helps a lot so I decided to have the boost on at all times and be able to use the “FAT” switch as it normally operates. With the right speaker and mod’s, the Fender Blues Junior is probably the best 15 watt amp commercially available for harp players who want versitility in a small portable amp. After the mod’s it has more than enough volume to use at gig’s or at home. Contact me if you have any modification questions or if you have an amp that you’d like modified and we’ll take a look at your options.

The “Harp Fanatic” Amp

I have decided to now build and offer a genuine boutique quality, harp specific 4X10 amp, based on the amp I built for myself, and a certain few others. The way I look at it, if you’re going to dole out the big bucks for an amp, it should have top quality construction, top quality parts and top quality tone. You’re not going to get that from amp kit’s, or amp’s that are built by companies who build them on an assembly line. To get true boutique quality from an amp, it must be built by a skilled and knowledgable person from the ground up, one at a time. You’ll likely never see two boutique quality amp’s that are identical in every way. My Harp Fanatic amp is built one at a time, by one person, (that would be me) with strict attention to detail in every aspect of the amp from top quality parts and construction to the way it looks and the way it’s designed, and especially, the way it sounds. Every aspect of the amp was carefully thought out and assembled in a way that affects performance, durability, and most important, TONE.

The core of the amp is based on the infamous Fender 59 Bassman 5F6-A circuit. There have been many copies of this amp built and designed based on this circuit because of its unmatched vintage tone. The 59 Bassman was originally built to be a bass guitar amp, but never really became a popular bass amp. However, it did quickly become a favorite among guitar players, and it also turned out to be one of, if not the best stock guitar amp for harmonica players. Fender re-issued the amp in 1994 and is still building them although some recent changes have been made to the amp. Even the re-issues are good harp amps right out of the box, but with the right modifications, it’s one of the best harp amps there will ever be.

You’re probably thinking, oh no, not another 59 Bassman clone amp! NOT EVEN CLOSE! The final circuit design is about 25% if that, of same value components, mainly resistors, and it also incorporates a “resonance circuit” not found on other Bassman clone amps. The cabinet dimensions are slightly different as well, but the cabinet design is the same. All components used in the making of the HF amp are upgraded and some are hard to find high quality vintage parts such as the ceramic tube sockets. Some are top of the line high tech parts such as the teflon insulated silver tinned copper hook up wire used throughout the amp. All of the components that affect the sound were hand picked after many months of testing and evaluating them for the best tone. From top to bottom, the HF amp is made with top quality parts by hand and attention to quality is a top priority. You will not find a better made amp anywhere in the world, and that is my promise to you.

The Harp Fanatic amp was designed and tuned to have the 59 Bassman personality, but modified to have more low end response, more crunch and distortion, and much more volume before feedback. It’s not as clean sounding as a stock 59 Bassman. It retains the distorted tone even at low volume settings. I designed it using perfectly matched 5881 power tubes, matched for Gm and within .5mA’s current draw at idle. Having perfectly matched power tubes will give an amp a cleaner tone than mismatched tubes. I used matched tubes purposely so that I could make the circuit design produce the distorted sound without having to rely on the tube distortion. The amp can get really raunchy if that is the tone you prefer by using mismatched tubes, or use matched power tubes for a lesser distorted tone. Using mismatched tubes will not hurt an amp as long as they are running within the recommended parameters. The amp does have an adjustable bias control that adjusts both power tubes simultaneously. If you want a real clean sounding amp, the Harp Fanatic is not for you. If you need an amp that has pure Chicago blues harp tone, and one that will cut through a loud band and sound great at lower volumes too, look no further.

The amp I am offering is the result of year’s of experimenting and fine tuning of the finished amp, with strict attention to detail and the highest quality parts. The components were carefully chosen for the highest quality, values, and tonal characteristics right down to the hookup wire which is all silver plated high purity stranded copper and teflon insulated. The amp also incorporates a “resonance circuit”, a feature that other Bassman type amps do not have. This control will allow you to mellow out the tone and give it a slightly softer bite, or turn it up to give the amp an “in your face” punch. So far the response to the amp has been outstanding. If you are interested in what I am building, (and believe me when I say that this amp is in no way shape or form, a copy of, or even close to a copy of any other modified bassman, or any other amp being offered by anyone anywhere), feel free to contact me via email for more details.

The amp is made with the best components available today as long as they continue to be available. If you would prefer certain component brands that are still available, I will be happy to discuss using the components with you, however, I will not use any parts that may affect the quality of the tone. I will be using a custom made cabinet, built by an extremely talented cabinet builder, and will be built to the highest quality standards as well. You will also have a choice of fine wood types of which to have it built from if you so desire the look of fine furniture. The cabinets are built using glued dove tail corner joints with all wood types. Finger jointed corner joints for pine cabinets that will be covered with tweed or tolex can also be ordered. Tolex is available in an assortment of colors if you desire a tolex cabinet covering. Some exotic wood types will be available at an additional cost upon request. Also, many of the high quality Riken 1% precision resistors are no longer available in the values needed, but I will continue to use whatever values are available until they too are gone. I will be substituting the values no longer available with other top quality 1% precision audio grade resistors.

The fine wood cabinets will come “ready for finishing”, so that you may put a custom finish of your choice on it, or you may order a tweed or tolex covered cabinet from one of the usual suppliers who offer pre made cabinets. These cabinets are nowhere near made to the quality standards of the custom made cabinets I offer and are not the exact same size of the custom cabinets either. I don’t recommend these cabinets but I do offer the use of them to those who would like to reduce the total cost of the amp. Email me for wood types available, more details or any questions you may have, or, if you would like to see some of the comments I have received from the people who are using my HF amps, or other amps that I have modified.

Feel free to contact me at GRBULLETS2@AOL.COM.