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what amplitude a signal going to guitar amp

hello,

I'd like to make a sine wave generator that I can play through a guitar amp... or bass amp for that matter... I imagine the signal coming out of a guitar into an amp is pretty tiny... I was wondering if anyone could tell me around what amplitude range I should make my signal so that it's comparable to that of a guitar or bass....

also, is there any kind of impedence matching or anything I need to check with the amplifiers input impedance and the circuit I'm making? I would guess not, because I just tried to measure the resistance looking into my amp... and it's like a meg.... but i hear a lot about impedence matching and speakers being 8-ohms and 4-ohms and such....

much thanks!

Reply to
panfilero
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Output from guitars can be as low as 10 mV and as high as 1 V or larger (especially in the case of active pickups or active circuitry). But for passive pickups somewhere in the 50 to 200 mV range is typical.

As for impedance matching, don't worry about it. Impedance matching is important for power transfer -- like when you go from your amp's output transformer into speakers -- but is irrelevant at the other end of the signal chain. You're interested in good *voltage* transfer basically, which means that you should try to keep the output impedance of your device well under 1 megohm, which by the way is a typical input impedance for most guitar amps.

Reply to
RichL

r

cool, thanks that's exactly the info I was looking for!

Reply to
panfilero

For what it's worth, 0db is defined as 1 volt, peak to peak, across a

300 ohm load.
Reply to
Tom

Huh? 0dBm = 1.5492V P-P across 300 Ohms.

...Jim Thompson

--
| James E.Thompson, P.E.                           |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
 I love to cook with wine     Sometimes I even put it in the food
Reply to
Jim Thompson

He didn't say "0dBm". He said "0db", whatever that is ;-)

0dBV is 1Vrms (impedance not specified).
Reply to
krw

Yup. "itsme" is now "itshistory" ;-)

...Jim Thompson

--
| James E.Thompson, P.E.                           |    mens     |
| Analog Innovations, Inc.                         |     et      |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
| Phoenix, Arizona  85048    Skype: Contacts Only  |             |
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  |
| E-mail Icon at http://www.analog-innovations.com |    1962     |
             
           Liberalism is a persistent vegetative state
Reply to
Jim Thompson

dBs are relative, so 0 dB can be anything.

John

Reply to
John Larkin

All of which does nothing to enhance the OP's knowledge.

Try this and try Google next time before asking a question. Google

electric guitar pickup voltage level

and see how many answers you get like this one

answers.yahoo.com/question/index?qid=20080609130810AAnq2T5 - 29k -

Jim

-- "It is the mark of an educated mind to be able to entertain a thought without accepting it." --Aristotle

"Jim Thomps>

Reply to
RST Engineering (jw)

Perhaps not. Misinformation doesn't enhance the OP's knowledge either.

Why? Doesn't interest me.

Reply to
krw

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