GUITAR BUFFER/PREAMP

Hi all I hope I in the proper forum .

I want to build a similar preamp like this one :

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Can you offer a relevant similar schematic as such ?

Elico

Reply to
RealInfo
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Try to google mc4558.

or

mc4558 guitar amp

Reply to
hamilton

That'll get you schematics, but not any over the top ad copy -- for that you'll have to go to your Thesaurus.

Antique Electronic Supply sells books on building guitar amps, not all of which will be about vacuum tubes. I suspect that your local guitar store and Amazon.com are also rich sources for books.

Knowing the whys and wherefors of getting a good sound may help you as much as getting schematics for things that are known to work.

--
Tim Wescott 
Control system and signal processing consulting 
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Reply to
Tim Wescott

You will find out that for really hard strums a single 9Vdc battery supply is NOT enough! Either use two, or add a DC-DC converter stage.

With the preamp right at the guitar, you'll miss the 'peaky' resonances some guitar players like. But, you could probably add a switch in cap to duplicate the ong run cable capacitance

From designing guitar preamps around 30 years ago, TI makes a great preamp chip very linear, 3-4nV/rtHz input noise and can run off +/-

9Vdc batteries. They probably make much better chips now. Don't be misled in your search just because an amp can go rail to rail doesn't mean that it's working very well when it does that. I've usually had to stay over 2.7+ V away from each rail to keep distortion below 1%.

Inspection of your link shows an EXTREMELY simple amp, you could pretty much copy it if you wanted to.

Reply to
Robert Macy

Yes, but will you get "exquisite tonal characteristics: a nice low end; clear mids with a touch of warmth; upper mids with a great ring quality; and clear, sweet highs"?

You know, I think too much attention has been paid to making audio equipment out of wires and vacuum tubes that have been dipped in liquid nitrogen. I think that it's time that we bring audio phoolery into the

21st century.

Yes -- I'm talking about making electronics that start with circuit board stock made using glass fiber that's spun from black Hawaiian obsidian, and epoxy resin that's hand-formulated by Genuine Europeans (in Europe!), using oil from carefully selected North Sea wells, and who are wearing lab coats and safety glasses designed by Armani.

Of course, if there's ever an eruption that spews out obsidian lava, the best circuit board glass fiber will be made by spinning the stuff in its virgin state, without ever letting it cool.

--
My liberal friends think I'm a conservative kook. 
My conservative friends think I'm a liberal kook. 
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Reply to
Tim Wescott

RealInfo used his keyboard to write :

check out ramseyelectronics.com for amplifier kits. easier way to go.

Reply to
OldeGuye

"Months of development and testing" ? Looks like one opamp maybe.

--
John Larkin         Highland Technology, Inc 

jlarkin at highlandtechnology dot com 
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Reply to
John Larkin

Sure but opamps are amazing these days. That might make them not so good for guitar amps though; is clipping a good or bad thing?

George H.

Reply to
George Herold

"Robert Macy"

You will find out that for really hard strums a single 9Vdc battery supply is NOT enough!

** What utter bollocks !!

Pre-amps with 9V supplies are used in a great many guitars and are 100% FINE.

This sort of alarmist bullshit is NOT welcome here - pal.

.... Phil

Reply to
Phil Allison

Look at Ebay item number 300852388218 There is not a lot of information at the web page you listed. My thought is that it is priced way higher than the cost of manufacturing and they do not want you to be able to check the specs against other preamps.

Dan

Reply to
dcaster

RealInfo

Look at Ebay item number 300852388218

** Why?

It is a completely different thing.

... Phil

Reply to
Phil Allison

Enough for what? What are you running this guitar cord into? Pretty much anything you plug an electric guitar into will clip before your 9V-powered buffer does. Note the classic Fender input stage clips at +- 2 or 3 V, and nobody would say that a Fender Twin isn't a 'clean' amp.

I'm familiar with the gross 'pffflunk' sound you mention. This will happen if you run the signal through a low-headroom buffer so it clips on peaks, and then pad it down. That'll bring the op-amp clipping down to a level wh ich can be reproduced by a real guitar amp. So don't put an attenuator aft er the buffer. If you want one, (although most guitars have perfectly good ones built in), put it before/in the gain stage itself, not after.

Reply to
morris.slutsky

I am not a guitar player, so I missed the word acoustic. I thought the Ebay item was a guitar preamp plus a 5 band equalizer

But the original poster ought to look at Ebay to find either pcb boards or assembled preamps.

Dan

Reply to
dcaster

"Phil Allison"

I am not a guitar player, so I missed the word acoustic. I thought the Ebay item was a guitar preamp plus a 5 band equalizer

** The Ebay item is a conversion kit for an acoustic guitar to make it "electric ".

The various boxes go INSIDE the guitar - so you need plenty of room.

The OPs little unit is fitted into a solid body guitar by carving a cavity in the back - if the ones already there are not big enough.

But the original poster ought to look at Ebay to find either pcb boards or assembled preamps.

** It's bad manners to tell someone to go look in some place - when YOU have not bothered to do so.

... Phil

Reply to
Phil Allison

ave

I agree. I did look but found so many possible candidates that I though the OP ought to look. I might suggest a preamp that is too big or miss some other unstated requirement.

Dan

Reply to
dcaster

The little bit I looked at tells me there is a high frequency loss when cabling is added between guitar and amp, also a tonal change when adjusting the volume from bigh to low on the guitar. So adding the preamp can decrease these affects, but the preamp must be put in the proper position in the chain depending on what you want to achieve.

I found a pdf manuual for the CB-2, but no schematic and as you see they scratch out the IC number. $125 is way more than the cost to produce and market this device.

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Here is a different preamp. Cost is a little better at $47.

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$49 If it were my money, I'd try this one.

Here's a Velleman guitar preamp kit, $29.

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If you really feel the burn to build a preamp, here are a few circuits.

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A bunch of kits here.

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Some education.

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Mikek

Reply to
amdx

Hey, there is a lot of effort in doing blindered, dumb and drunk testing.

?;-P)

Reply to
josephkk

It pretends.

Reply to
josephkk

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