Guitar amp what driver to use?

[Boscoe]

Didn't really know where to put this but I was wondering what sort of driver I needed and what sort of frequency response I need for a regular guitar, Do I need to change anything from making a regular enclosure?

I'm thinking of THIS but have no idea on parameters or anything!

I'm looking at 100Wrms 12"

Thanks
Boscoe

[turboyam]

If you like a vintage sound, there is Celestion and Jensen. Check Eminence
drivers too, they have a huge choice.

[epitaxial]

The Peavey will come in close to the Jensen and Celestions. A very light and thin cone will be the way to get the "speed" of the guitar's strings to reproduce, but if you ar attempting to improve your sound, don't rule out pickups. Also keep in mind that if you want your sound to stay consistent with volume, the IC amps DO NOT CHANGE the sound of your guitar as the volume is raised, but a tube will add achieve some "auto smoothness" to the rough high end roll off of the "crude" ancient driver. If you want the most accurate sound of your guitar, something like a Fostex full range may be the best, with an IC amp, driven with a two stage Class A transistor preamp (low noise mic preamp).

(Sorry if this appears to be a hi-jacking, but I've seen some crazy and cheep combinations use to amplify some fabulous guitars.)

[Boscoe]

No thats great thanks.

[Racket Scientist]

There are a number of differences from "a regular enclosure". First thing is to realize that most guitar amps don't reproduce the input signal very accurately, and they're not expected to. They color the sound in a characteristic way we've come to like, and certain types of distortion and coloration are actually sought after. There is a whole subculture of guitarists who sweat the details of guitar and amp tech in the same way as DIY audio is here, and a whole range of speakers with various types of coloration that are employed. There are a few areas, such as jazz and acoustic guitar, where sometimes not much coloration is desired and a fairly close reproduction of the signal is sought, but thats not the norm.

The quick and easy answer is that you need a speaker designed for a guitar amp from a reputable maker. The more in depth answer requires more information, such as the style you play, the guitar and pickups, what type amp you have, what artist's sounds would you like to mimic, etc.

For hours of reading on the subject, look over "The Gear Page" guitar forum. For suggestions from me, give some of the info listed above.

[Racket Scientist]

I also would have suggested putting this in the "Musical Instruments" section; maybe the mods will move it.

[Boscoe]

Okay thanks for the advice and I don't know half of that as I'm looking into making this for someone, the amplifier everything but I don't think it's do able on his budget.

[Racket Scientist]

If the budget is limited, I'd consider looking for a used solid state guitar combo amp rather than DIY. My usual suggestion is an older Peavey Bandit (Transtube model).

If you really want to DIY a guitar amp on a budget, look over the web for advice, build a simple pine open back cabinet (don't worry about Thiele Small parameters or anything) and mount a guitar speaker in it (in USA Eminence are the best value, but in UK probably a Celestion). Then track down a vintage mono PA amp (Newcomb, Bogen, etc.) and change out the electrolytic caps and bring it up to good working condition. Finally, replace the input and output jacks with 1/4 inch phone jacks to make it compatible with guitar stuff. Those make killer sounding guitar amps.

[wakibaki]

Originally Posted by epitaxial

If you want the most accurate sound of your guitar, something like a Fostex full range may be the best, with an IC amp, driven with a two stage Class A transistor preamp (low noise mic preamp).

I definitely recommend against this approach. What Racket Scientist says is good sense. You want a guitar speaker, not a hi-fi speaker. It should go in a large open- or semi-open-back box, not a regular enclosure (this is regular for musical instrument cabs, go look at some). The Peavey is a good choice on a budget, particularly if the player is a novice and is unsure what kind of sound they prefer.

Most successful DIY guitar amps are valve (tube) amps. Solid state can easily end up sounding too clean with unpleasant overload characteristics. A SS amp can work if it's got plenty of headroom and it's preceeded by an effects processor such as the Sansamp. The traditional guitar amp makers all produce SS amps now, but they go to some lengths to get acceptable tone. You are unlikely to get this at your first try. An exception to this is a bass amp, these are more often SS with a sealed or ported enclosure and sometimes tweeter reinforcement.

If you build a tube amp use a known circuit (or close to) with a tone stack and do not overspecify the power and output transformers, or again you will end up with too clean a sound. A spring reverb is nice.

w

A few last words, it's very difficult to build a guitar amp cheaper than you can buy one of equivalent or better quality and probably greater versatility off-the-shelf. Absolute power may not be the consideration it once was, depending on what PA is available, there's a lot to be said for an amp that works good without upsetting the neighbours.

[epitaxial]

Another consideration will be volume if the amp is a low powered tube amp, or accuracy if you rely on pedals (such as the germanium, FET, or tube) and emulators to make the sound. But the cone weight should be as low as possible to get the unrestrained sound. A smooth HF response is nice too. But every speaker sounds a bit different.