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Old 09-09-2012, 06:28 PM   #1
pauldude
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Default A simple DIY preamp for guitar....maybe the cheapest on the planet?

I've notice quite a few posts from beginners about plugging their guitars directly into a computer's built-in soundcard. I guess some people might not be able to afford the cost of even a cheap store-bought interface.

(Just came across this site - this preamp has a good reputation....tube-like warmth, to quote: http://www.hawestv.com/amp_projects/...fetpreamp1.htm which has a ton of info about the preamp and using alternatives to the transistor used in the original design)

I found this site which shows you how to make a preamp using just seven components and a 9V battery. You'd also need two guitar-plug sockets, an extra guitar cable and a 1/4 to 1/8 plug adapter if you didn't fit it into your guitar as shown but used it externally (economy tips at the end of this post):

http://www.diyguitarmods.com/guitar-preamp.php

The guy shows how to fit this inside a guitar but you could put it into a small metal box with input and output sockets and use it between the guitar and the computer.

This site has a link to the site of the guy who designed it, which is here:

http://www.till.com/articles/GuitarPreamp

Plenty of info - the designer shows how this can be built into a guitar cable plug! Control pots can be added also, in place of fixed resistors.

I think the main feature is that this preamp matches up the impedances correctly - high impedance input from the guitar and low impedance output to the computer. That should eliminate the sound quality problems caused by the impedance mis-match which results from a direct guitar input into the soundcard. It seems the preamp does produce a good tone too.

I'll be building it as soon as my field effect transistor arrives, and will report back.

Cheap as chips! Google "J201 semiconductor" to get a price on the transistor, or try "MPF102 semiconductor" (I just bought this here, for 89 British pence plus despatch ): http://www.dayga.co.uk/Semi_Conducto...A_To_92_Case_1) if the J201 is hard to locate or only available in quantities of 100 or has a high minimum-order fee, and refer to the url in bold above to get the mod specifications). The other components could be snilched from old electronics units. Google again to get "resistor colour codes". Capacitors usually have their values printed on them in numbers and farad symbols.

And 9V is a pretty safe level to be toying around with. The circuit is very simple indeed. If you are new to practical electronics and don't fancy doing it yourself, it wouldn't take an experienced friend long to put it together for you to try out. A little more time would be needed to get it mounted nicely in some kind of metal box with the input and output sockets on it.

Disclaimer:

Please don't blame me if....etc etc .

Note:

If you need to scrimp on the cost (or want to keep costs to a minimum until you've tried it out) and not buy an extra guitar cable, you could scavenge a lead which has a 1/8 plug on the end. These are often stereo, so just twist the coloured wires together. Connect this lead to the output from the preamp and that would go into the computer....wouldn't need to be very long. You'd also save on the cost of the preamp output socket.

To save the cost of the preamp input socket, you could sticky-tape the input wires of the pre-amp to the correct points on your guitar cable plug.




.

Last edited by pauldude; 09-09-2012 at 09:12 PM.
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Old 09-10-2012, 01:18 AM   #2
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J201s are end-of-life and hard to find. Sadly, they're also the nicest sounding /feeling. MPF102s aren't so great for distortion but have served me fairly well in mic pres.

I wouldn't build it into a guitar plug because it's incredibly difficult to work in such a tiny space. That is, I broke lots of jfets trying with a similar circuit.

Another problem can be headroom at 9v with high output pickups if you want a clean DI, and finding the right value for R2 can be tricky (you could use a trim pot but they drift). Trust us here, you'll want more headroom unless you're using it with a low output tele or strat pickup, or don't mind MPF102 distortion.

Since the circuit is so simple there's a ton of variations to have fun on a rainy day.

-robo
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Old 09-10-2012, 04:36 AM   #3
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Quote:
Originally Posted by robo View Post
J201s are end-of-life and hard to find. Sadly, they're also the nicest sounding /feeling. MPF102s aren't so great for distortion but have served me fairly well in mic pres.

I wouldn't build it into a guitar plug because it's incredibly difficult to work in such a tiny space. That is, I broke lots of jfets trying with a similar circuit.

Another problem can be headroom at 9v with high output pickups if you want a clean DI, and finding the right value for R2 can be tricky (you could use a trim pot but they drift). Trust us here, you'll want more headroom unless you're using it with a low output tele or strat pickup, or don't mind MPF102 distortion.

Since the circuit is so simple there's a ton of variations to have fun on a rainy day.

-robo
Thanks for the info, robo!

The guy at the url I gave in bold goes through a trial-and-error procedure for getting the optimum value for this resistor....just pulling one out and dropping another in and measuring the voltage. This of course involves the use of a voltmeter so may not be for the totally inexperienced.

I was looking around for something like this because I was sure there must be something quick and simple and cheap to get the impedances matched up for plugging a guitar into a built-in soundcard.

It's probably, as you say, something to play around with on a rainy day more than a noob option. Once one has a guitar, a computer and stuff I suppose the cost of a basic interface wouldn't stretch the bank much further.

It all adds a couple of drops into the pool of knowledge, though, so I posted it up. It seems that practical electronics at home has been on the decline over the past couple of decades, mainly due to the disposable products were are presented with these days. Just throw away and buy another! It is getting harder to repair stuff because of the shrinking size of components.

But there is still stuff to explore and play around with to get a better understanding of basic electronics, especially for plugged-in musicians.


Remember - high voltages and currents can kill!

.

Last edited by pauldude; 09-10-2012 at 08:21 AM.
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Old 09-10-2012, 06:49 AM   #4
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Hi
I've been looking for a circuit to make a pre-amp for an Epiphone Chet Atkins thinline acoustic-electric (actually a chambered solid body - not really acoustic at all in the real sense) so I'm really interested in this. I think I can probably manage to build the one shown and I can easily get the MPF102 FET (£1.60/$1.10 for 5). So, as distortion isn't really going to be my main concern would this pre-amp circuit be suitable? I think the piezo pickup needs a very high impedence input (5 mega ohm or more I've been told). Thanks in advance for any advice on this.
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Old 09-10-2012, 06:53 AM   #5
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Thanks for the info, robo!

The guy at the url I gave in bold goes through a trial-and-error procedure for getting the optimum value for this resistor....just pulling one out and dropping another in and measuring the voltage. This of course involves the use of a voltmeter so may not be for the totally inexperienced.

I was looking around for something like this because I was sure there must be something quick and simple and cheap to get the impedances matched up for plugging a guitar into a built-in soundcard.

It's probably, as you say, something to play around with on a rainy day for those who know what they are doing more than a noob option. Once one has a guitar, a computer and stuff I suppose the cost of a basic interface wouldn't stretch the bank much further. But the impedance-matching properties of the preamp might be useful to someone, somewhere, sometime.

It all adds a couple of drops into the pool of knowledge, though, so I posted it up. It seems that practical electronics at home has been on the decline over the past couple of decades, mainly due to the disposable products were are presented with these days. Just throw away and buy another! It is getting harder to repair stuff because of the shrinking size of components.

But there is still stuff to explore and play around with to get a better understanding of basic electronics, especially for plugged-in musicians. The info on the webs sites to which I posted links is well-written and informative and might be a good first step for anyone wanting to learn more about this subject.


Remember - high voltages and currents can kill! Licking the terminals on a 9V battery tickles the tongue (has everyone done this ?) but mains voltages and currents are a serious business!!!

.

Last edited by pauldude; 09-10-2012 at 08:21 AM.
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Old 09-10-2012, 07:33 AM   #6
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A company with good reviews on Ebay has some J201 transistors on offer, at $2 (GB 1.25) each:

http://www.ebay.co.uk/itm/Transistor...item5ae139443c

Seem to be plenty around still - the trick is finding a seller who will do small orders.

.

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Old 09-10-2012, 07:44 AM   #7
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Quote:
Originally Posted by pauldude View Post
A company with good reviews on Ebay has some J201 transistors on offer, at $2 (GB 1.25) each:

http://www.ebay.co.uk/itm/Transistor...item5ae139443c

Seem to be plenty around still - the trick is finding a seller who will do small orders.
I had a look at that eBay item and it's $2.00 for 8 transistors. Thanks for the link.
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Old 09-10-2012, 07:51 AM   #8
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You're welcome.

Here too:

https://sslrelay.com/doctortweek.co....2smPfYllOguygl

Plenty around still, for sure. Apparently it's a good idea to use a couple of diodes to protect these things....see:

http://www.hawestv.com/amp_projects/...fetpreamp6.htm

.

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Old 09-10-2012, 08:02 AM   #9
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....and here, with normal despatch costs ($1 each and $4.35 despatch to Europe):

http://www.tubesandmore.com/search/node/j201

The planet's oozing with J201s! Prices vary a lot but the most expensive are still going for peanuts. I was able to buy ten here and got a prompt order-confirmation email, so fingers crossed they're on their way.

I can't buy on Ebay - neither Ebay nor PayPal likes my address.

And here, although I don't know how much low-number ordering will cost. Sometimes they have a minimum payment and despatch for one can cost $40 . I didn't continue through to checkout:

http://www.futurlec.com/Transistors/J201pr.shtml

.

Last edited by pauldude; 09-10-2012 at 08:20 AM.
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Old 09-10-2012, 08:22 AM   #10
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Quote:
Originally Posted by tweezer View Post
Hi
I've been looking for a circuit to make a pre-amp for an Epiphone Chet Atkins thinline acoustic-electric (actually a chambered solid body - not really acoustic at all in the real sense) so I'm really interested in this. I think I can probably manage to build the one shown and I can easily get the MPF102 FET (£1.60/$1.10 for 5). So, as distortion isn't really going to be my main concern would this pre-amp circuit be suitable? I think the piezo pickup needs a very high impedence input (5 mega ohm or more I've been told). Thanks in advance for any advice on this.
Can't help, sorry. I'm not an expert in this field but can solder and enjoy doing new things.

The designer really seems to rate this preamp though, so go ahead and build it at the amazingly low cost and see how you go. Check the stuff I referred to earlier here, about trying out different resistors. You might strike gold !

.
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Old 09-10-2012, 12:22 PM   #11
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I believe paul is correct that you have plenty of voltage, and it's really a matter of impedance matching*. (A transformer is the normal/simple way to match/transform impedance, but a transformer won't work in this application because it would also lower the voltage.)


A buffer amplifer should do the trick. It has a gain of 1, high input impedance, and low output impedance.

Using an op-amp, you can build a buffer amplifier with 3 electronic components (plus the power supply, connectors, wiring and box.)

DISCLAIMER - Although I've built quite a few of these op-amp buffers, I've never tried one in a guitar application.

An op-amp generally requires a positive & negative supply (i.e. two 9V batteries). The power supply connections are not shown on the schematic I linked to, and it's standard practice to use a bypass capacitor (typically 0.1uF, value not too critical) across each power supply, mounted close to the chip (also not shown on the schematic).

Or you can create a virtual ground and run it from a single power supply, but this requires 4 more components - A pair of equal-value resistors to make a virtual ground (i.e. at 4.5V) plus a capacitor on the input (maybe ~0.1uf or more) & output (maybe ~1uF or more) to block the 4.5V DC bias from the virtual ground.

If you are going to plug-into a laptop (with only a mic input)you need an attenuator (i.e. 2-resistors an a voltage divider) and/or a pot to knock-down the buffer amps output-voltage by a factor of somewhere in the range of 10 to 100. ...But you probably don't want to use a laptop anyway, ince the built-in mic preamps are generally lousy quality.

Op-amp circuits generally have great performance, but a "standard design" like this does not distort "nicely"... If you overdrive it, it simply hard-clips. That's usually OK, since you are probably going to use some amp sims or other software plug-ins anyway.



*
Technically, you don't really want to "match" the impedance of the guitar pickup. You want a high-enough input-impedance on the preamp (1M Ohm or more) so that the signal from the (high-impedance) pickup doesn't get "dragged down" by the preamp's input-impedance, and/or so the load impedance (as seen by the guitar) doesn't change the character of the sound.

Then, you want a low-impedance output from the buffer/amplifier (~1K Ohm or less) so that the input impedance on your line-level (or mic level) soundard's input (~10K or more) doesn't "drag-down" that signal.
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Old 09-10-2012, 02:29 PM   #12
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^^^^

Cool stuff! Thanks for posting.

You are right about the "impedance matching" phrase. It's a bit 'loose' really, but it's the one that gets used a lot in web discussions and articles. I see it as meaning "matching from two sides" - the guitar output matches the preamp input (more or less) and the preamp output matches (more or less) the soundcard input. It has nothing to do with matching the input to the output, ie making them have the same impedance.

I have an interface on my main music computer (I'm on a laptop as I type), which is a console that links to my Audigy soundcard. I got curious about how to get the best from a direct guitar input into the laptop soundcard, which is abysmal at the best of times. The direct connection was awful, and then I found out I could use my delay pedal as a pre-amp, without having to use the fx. I got a much better result with the sound.

Then I started to wonder about the cheapest possible way to improve the sound quality of a direct input into a soundcard not designed for the job, and started surfing to find out. I'm looking forward to learning yet more here, hopefully.

I think I'm in the early stages of building myself a decent tube amp.

I am here at the moment:

http://en.wikipedia.org/wiki/Buffer_amplifier

and....

http://www.muzique.com/lab/buffers.htm


I'd be grateful to learn what transistors can be used in the buffers shown at the muzique.com page I just referred to - yet another informative page which is quite understandable.


.

Last edited by pauldude; 09-10-2012 at 02:38 PM.
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Old 09-10-2012, 02:45 PM   #13
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Quote:
Originally Posted by tweezer View Post
Hi
I've been looking for a circuit to make a pre-amp for an Epiphone Chet Atkins thinline acoustic-electric (actually a chambered solid body - not really acoustic at all in the real sense) so I'm really interested in this. I think I can probably manage to build the one shown and I can easily get the MPF102 FET (£1.60/$1.10 for 5). So, as distortion isn't really going to be my main concern would this pre-amp circuit be suitable? I think the piezo pickup needs a very high impedence input (5 mega ohm or more I've been told). Thanks in advance for any advice on this.
Aha!!

I posted earlier that I couldn't help, but I am learning. There is a reference to piezo pickups here:

http://www.muzique.com/lab/buffers.htm

....fourth paragraph (not read further than that yet).

.
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Old 09-10-2012, 03:08 PM   #14
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Here is a little bit of general information regarding tubes, amp etc :

http://www.tubebooks.org/technical_b...rcuit%20design

Diving in now....I have decided to study this subject. It's all quite mysterious at the moment, but I have the webbynet!

.
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Old 09-11-2012, 02:31 AM   #15
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Thing about op amps is the crossover distortion can be a problem since they're class AB. You will want a really nice (expensive) op amp like an OPA134 or better. You'll also want much greater than 9vDC.

Dual voltage psu's are easy to make. A simple example can be found here: http://electronics-lab.com/projects/...011/index.html

tweezer, JFETs love high impedance sources like piezos and rhodes keyboards.

pauldude, if you need any help understanding tubes I'm glad to lend my experience. The book you want from pmillet's site is Radiotron Designer's Handbook Volume Four. It's the bible and written for humans. A lot of the other books there are written for chemical engineers and nuclear physicists, and some for children

Don't fear voltages. Fear current.

-robo
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Old 09-11-2012, 04:06 AM   #16
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Quote:
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Thing about op amps is the crossover distortion can be a problem since they're class AB. You will want a really nice (expensive) op amp like an OPA134 or better. You'll also want much greater than 9vDC.

Dual voltage psu's are easy to make. A simple example can be found here: http://electronics-lab.com/projects/...011/index.html

tweezer, JFETs love high impedance sources like piezos and rhodes keyboards.

pauldude, if you need any help understanding tubes I'm glad to lend my experience. The book you want from pmillet's site is Radiotron Designer's Handbook Volume Four. It's the bible and written for humans. A lot of the other books there are written for chemical engineers and nuclear physicists, and some for children

Don't fear voltages. Fear current.

-robo
Thanks again, robo! I'm sure I'll have some questions soon.

I'll check out that book you mention. I started reading some yesterday and really can't handle the more complicated maths. I have a general understanding of audio circuitry from my childhood, and can follow the anode and cathode voltage and current equations okay. Once an equation gets longer than an inch on the page, I'm squirming .

At 57, I was around ten years old when people started throwing out their old gramophone cabinets for newer stuff, and some came my way. I got a local reputation as a repairer after I discovered that most problems were bad connections caused simply by the heat and the passage of time. My technique was to press circuit boards and knock components with a foot-long dry wooden rod as a record or the radio was on, to locate the source of the problem. This worked nearly every time . Once I had learned how to repair a cracked circuit board track with solder, I was away. Most things can be fixed, I've found over the years. Maybe this thread wil inspire some to delve into the subject.

I know about the voltages/current issue but I mentioned both to make it a rounded warning to a novice.

There are plenty of sites on the web dedicated to DIY fx boxes. I'm getting into it so I can learn more about guitar sounds and what it is that makes a great amp like a Marshall great. I have a Carlsboro amp from the eighties and a Boss DD-3 delay pedal, so I don't have much experience at all when it comes to guitar sound.

With careful soldering and de-soldering, a set of components and be used over and over in different configurations. Once I have the basic stuff and learn some theory I can start playing around with my own designs, which seems like a cool thing to do.

For young guitarists embarking on the road to a professional career, studying this could only help. Even if just at the BS level at parties:

"Well I say it's all about the grid bias, and metal film is the way to go."



Not quite a REAPER discussion here any longer....this thread only had a tentative link to REAPER and has now morphed into something else. Perhaps a move to the lounge might be in order? I'm easy.

PS....

Found the Radiotron book., thanks. A tip for Firefox users, something I discovered recently (other browsers have a similar function I believe):

Hitting the forward slash brings up a small window, bottom left of the browser window - "Quick find". Just type in the word you want to search for and the target word gets highlighted on the page.

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Old 09-11-2012, 04:58 AM   #17
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I found this just now, which seems useful for learning stuff:

"The Tone Stack calculator is designed to help you check out the design and response curves of a variety of tone stacks used in popular guitar amplifiers."

http://www.duncanamps.com/tsc

Works on XP, though not listed in the OS specs. You can change components and check the effect of the change on a frequency/decibel graph. Ther are three sliders - bass, mid and treble. Fender, Vox and marshall amp tone stacks included.

Just need something to mod now. Could be a while yet .
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Old 09-11-2012, 05:19 AM   #18
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@ robo....

Any thoughts on this as a first guitar amp project?:

http://www.ax84.com/p1.html

Looks good to me.

Thanks in advance,

Paul.
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Old 09-12-2012, 03:44 AM   #19
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AX84 projects are great!

They have an awesome community and I believe they helped with Revalver development.

Here's another great book from an ax84 super guru: http://www.amazon.com/Designing-Tube.../dp/0956154506

Also banging things with a stick is a normal troubleshooting method. I use chopsticks or a drum stick to slap around for funky joints and microphonics, and to move wires around in risky spots.

Tubes are really awesome low-level, direct electron field manipulation devices. In the near future we're getting carbon nanotube triodes and pentodes which will be fun.
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Old 09-12-2012, 04:49 AM   #20
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Thanks, robo! I'll dive into the aforementioned project then. Continuing to read....just around and around and things are starting to sink in.

Yeah, tubes. I think for me it's also a bit of a nostalgia trip. I can still remember the smell of a warm mahogany cabinet and the slightly eerie glow of the tubes.

Re knocking with sticks - all these years I thought I was mad :0! I didn't have a multimeter back then so I didn't have too many options in troubleshooting.

After the AX84 guitar amp project I plan to do an audio amp to play my vinyl. More nostalgia! Nothing special initially - perhaps 10W with around 5% THD should sound pretty cool and not too expensive.

Re power supplies....

Could you recommend a kind of universal transformer that I could use for the guitar amp, and then re-configure to try out the audio amp before buying a second transformer. Or maybe I could build a guitar/audio combo amp on the same chassis and use just one transformer - not necesarily using the two together at any one time, although that could be sweet. Good transformers look pretty expensive, but I know it's important to have a good power supply with some reserve.

Cheers!

Paul.

PS....

I've just applied to join the AX84 forum. I had a shave and washed behind my ears beforehand, so I'm optimistic .

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Old 09-12-2012, 07:09 AM   #21
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I'd be grateful to learn what transistors can be used in the buffers shown at the muzique.com page I just referred to - yet another informative page which is quite understandable.
The buffer circuit is quite forgiving as to the jfet type. Almost any fet will do the job. Mouser still carries a few in the TO-92 package such as the J111 or J113, which can be used in the buffer.

regards, Jack
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Old 09-12-2012, 02:17 PM   #22
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If you're getting into electronics a little more, you definitely want to join the forum here:
http://www.diystompboxes.com/wpress/

Great bunch of guys, much like here at the Reaper forum, and one of them (RG) is the wiz behind http://www.geofex.com/.

Also, if you're getting into tube amps, you must have this: http://www.londonpower.com/catalog/p...?products_id=3

and you can get a lot of info off his site as well, particularly here: http://www.londonpower.com/tech_articles.htm

Kevin's an approachable guy (or at least he used to be, can't say for sure now since I haven't asked him anything in a few years); I had a problem with my amp that I was going to try to fix myself, and, as he had a question form, I contacted him describing the problem. I wasn't really expecting an answer, but he replied a day or so later and definitively said "this is what's wrong with your amp".

And he was right.
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Old 09-13-2012, 05:26 AM   #23
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Pauldude, any Hammond transformer for mains and output will do, or Edcor. Both are affordable.

http://www.hammondmfg.com/ for the models, http://www.tubesandmore.com to buy.

Edcor sells direct @ http://www.edcorusa.com
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Old 09-13-2012, 05:57 AM   #24
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Quote:
The guy at the url I gave in bold goes through a trial-and-error procedure for getting the optimum value for this resistor....just pulling one out and dropping another in and measuring the voltage. This of course involves the use of a voltmeter so may not be for the totally inexperienced.
Use a trimmer, adjust to desired point, measure resistance, replace with fixed resistor of that value ( or combination of resistors if it's an in between value ).
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Old 09-13-2012, 06:15 AM   #25
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Quote:
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@ robo....

Any thoughts on this as a first guitar amp project?:

http://www.ax84.com/p1.html

Looks good to me.

Thanks in advance,

Paul.
I love my AX-84 - very good sound and the tone controls and master give you a lot of flexibility. I built mine as a rack - but its easy to fit into a cab or whatever.












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Old 09-13-2012, 07:13 AM   #26
Jacko
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Here's my page with some pix of the AX84 that I built. It was one of the early prototypes while the design was being developed. I still use it in the studio because of its excellent tone.

http://www.muzique.com/ax84.htm

regards, Jack
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Old 09-13-2012, 03:54 PM   #27
pauldude
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Thanks guys! The pictures are inspirational and give good idea of how the schematic converts to the real world.

I got accepted at the AX84 forum and will be posting there as 'pauldude' soon.

We should get this thread on-topic somehow. Erm....I can't wait to record my new amp in REAPER.

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Old 10-24-2012, 09:57 PM   #28
Ianpb
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Default Tillman Preamp

Hi,

Just to let you know that I built this pre-amp using a J201 a while back and it does make the electric guitar sound good, rather like that full bodied quality you get when you crank a guitar and amplifier up loud whilst in clean mode. However, that was with a Squier Stratocaster with single coil pickups. When I connected a guitar with humbuckers (not hot output) it clipped badly. I then discovered that the bias was wrong (8.5v instead of recommended 6v) even though the component values were correct. I only managed to get the bias voltage to the correct 6v by adding a 20k trim-pot in series with R3 and adjusting it so that the total voltage (pot + R3) = 20k ohms. This also caused the preamp to amplify, which was not wanted, plus it was still just about clipping. I haven't done this yet but it's clear that for use with powerful (hot) humbuckers 18v supply is necessary to give the pre-amp more headroom, which will then add to the problem of fitting it inside a guitar together with two PP3 batteries instead of one, although maybe a small 12v battery might just about manage it.

I understand that the J201, like most jfets, can stray greatly from its specs, so I suggest that before assembling your preamp you try it out on a breadboard and experiment with your options from there - it's a lot easier than messing about with a soldered up job, which I ended up being forced to do.

I should add that you can add a switchable 10mfd capacitor across R2 to give it some nice treble boost.

I would suggest that anyone more interested in the technicalities and options of this Tillman pre-amp should have a read of this website:

http://www.hawestv.com/amp_projects/...fetpreamp1.htm

I hope that helps.

Last edited by Ianpb; 10-24-2012 at 10:02 PM.
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Old 10-12-2015, 10:32 AM   #29
eclecticguitarman
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Default Tilman like JFET preamps available

I have built several J201 JFET pre-amps that can be mounted internally or externally to an electric guitar. The pre-amps are powered via a standard stereo cable (TRS plug) and a power unit is also available. I've added a relay to the pre-amp so it is bypassed if power is not provided, so the guitar can still use a mono cable in a pinch. I am making them available on eBay and they're called the Road Runner Pre-amp.
Feel free to check them out at www.guitarpre-amp.com

Thanks,
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Old 10-12-2015, 01:20 PM   #30
stanley jones
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so...how do I navigate to the diy pre-amp from that page on the 1st link you posted?
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Old 10-12-2015, 02:59 PM   #31
karbomusic
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Quote:
Originally Posted by stanley jones View Post
so...how do I navigate to the diy pre-amp from that page on the 1st link you posted?
Don't know the answer but you can check out our very own DIY electronics thread over in the lounge.

Additionally diystomboxes.com should be able to handle anything you can possibly need in this area.

Lastly, a DIY guitar preamp/buffer is likely one of the easiest electronic projects out there.
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