[navin]

My son (age 10) is learning guitar.

He started with a beginner nylon guitar. Then he inherited an electric guitar as well as a Marshall 4001 (Studio 15) tube combo (6V6) and a smaller Marshall solid state (Lead 12) combo amp.

Now he was gifted a Yamaha CPX 900 Acoustic. The guitar has an electric pickup and he asked if he could get a acoustic amp. We live in a small apartment and I was loathe to get him a third amp so asked him to connect it to one of the combo amps above.

Would this combonation sound good? I would assume that between the 2 combos, the solid state amp would be a better match.

[silver_strings]

What an inheritance  , an acoustic has a wider frequency rannge though and an acoustic amp is better suited to hear the fuller sound but it will sound good through the ss amp.

[navin]

What an inheritance  , an acoustic has a wider frequency rannge though and an acoustic amp is better suited to hear the fuller sound but it will sound good through the ss amp.

Well the electric is a Fernandez Strat made in 1979 (FST 70 Stone Logo). The original pickups were very noisy so I upgraded the pickups to Lace Holy Grails and installed an N-tune and push pull volume pot for the N-tune.

Now the heads (tuners) are also rusting so I have ordered Kluson locking heads which should get here in 4-6 weeks.

[dflee]

Not familiar with the pickup on the acoustic. If it has a battery in it than it has the boost for a non accuostic amp. If not than other options need to be considered.

[navin]

Not familiar with the pickup on the acoustic. If it has a battery in it than it has the boost for a non accuostic amp. If not than other options need to be considered.

Yes there is a 9 v battery on the Acoustic. Would a D.I box like the one from LR Braggs help match the Acoustic to the Combo?

[srb]

Would this combonation sound good? I would assume that between the 2 combos, the solid state amp would be a better match.

Am I missing something here?  You already have in your possession the Marshall 4001 (Studio 15) and the Marshall solid state (Lead 12) amps as well as the Yamaha CPX 900 guitar?
 
So tell us how the guitar sounds with either amplifier.
 
Steve

[navin]

Am I missing something here?  You already have in your possession the Marshall 4001 (Studio 15) and the Marshall solid state (Lead 12) amps as well as the Yamaha CPX 900 guitar?
 
So tell us how the guitar sounds with either amplifier.
 
Steve

Yes I have all three in my possession. Common sense says that plugging the CPX900 into either amp should not harm anything. Correct? My son's guitar teacher told him not to connect the Acoustic to the combos. Any idea why?

I was wondering if I would need some load or impedance transfomer between the Acoustic and the combo amp.

[srb]

Well, I guess I'm guilty for going through life unabashedly plugging a variety of guitars and keyboards into a variety of amps, both tube and solid state, and even if the match wasn't ideal it hasn't yet posed a problem that damaged anything.
 
If I'm not mistaken both of those amps have a High and Low input (?).  The guitar has a preamp after its piezo soundboard pickups, so I doubt you will have too weak a signal.  But you could start with the attenuated High input and see.  One of them will probably work better in getting a greater usable range from the guitar's volume control.
 
Steve

[dflee]

SRB! The man knows his stuff

Don

[Ericus Rex]

My son's guitar teacher told him not to connect the Acoustic to the combos. Any idea why?

He could be a moron.

Do what SRB says.  If the pre in the acoustic is too hot for the amp you'll get unwanted distortion.  But other than acoustic amps shooting for the warmest sound possible there aren't any real differences between an acoustic amp and an electric amp.

As I side note, I have a work colleague who has been using guitar amps as bass amplifiers for 30 years.  Everyone tells him it shouldn't be done but he gets a great sound and absolutely HATES the sound of ss bass amps.  He doesn't need hundreds of watts and needs tubes so the only options for him have been guitar amps.

[navin]

Do what SRB says.

thanks SRB, Ericus Rex and co.

Ok I did and in the lo input the Lead 12 amp sounds very 'jangly". When I turn the volume pot on the guitar down the sound is very acoustic. When I turn the pot up so the amp lends a weird set of overtones to the sound. I saw some old videos of the Eagles playing live and the Acoustic guitars sounded natural like they would if there were no amplifiers.

On the hi input of the Lead 12 I got very little output. So I have gone back to playing with the tone controls on the amp and guitar to try and achieve sometching resembling a natural acoustic. Any pointers.

One friend suggested an Acoustic D.I. Box but I can't see how that would help. Would it?

[srb]

You've probably fiddled with the controls on the amplifier, but turning up the volume control and turning down the gain control should give you a less distorted overdrive sound.
 
Steve

[navin]

You've probably fiddled with the controls on the amplifier, but turning up the volume control and turning down the gain control should give you a less distorted overdrive sound.
 
Steve

Steve, thanks for walking me through this. When I turn the gain down ( as low as I can go without turning the guitar off) the sound quality is about the same. It does not sound like distortion but some weird jangly overtone or something.

[srb]

Obviously they do make specific acoustic guitar amps which are ultra-clean with a lack of any discernible distortion as opposed to electric guitar amps where some amount of distortion is desireable for electric guitar sustain).  I wonder if the solid state amp is working properly or if that is just the sound it has by design, although I guess you do not notice a "jangly" sound with an electric guitar?
 
Did you also give the tube amp a try?
 
Steve

[navin]

Obviously they do make specific acoustic guitar amps which are ultra-clean with a lack of any discernible distortion as opposed to electric guitar amps where some amount of distortion is desireable for electric guitar sustain).  I wonder if the solid state amp is working properly or if that is just the sound it has by design, although I guess you do not notice a "jangly" sound with an electric guitar?
 
Did you also give the tube amp a try?
 
Steve

The tube amp does not have enough gain. The Lead 12 sound very nice with the electric. Maybe Marshall introduced some characteristics to make the solid state sound like a over driven tube (typical in tube combos). The sound of the guitar with the amp is not as mellow as the sound of the natural guitar.

[dflee]

And it never will be!

[Ericus Rex]

The tube amp does not have enough gain.

There's something strange going on here.  An electric guitar with passive pickups has far less output than your acoustic with an active preamp in it.  The acoustic should sound louder than the electric.  Not the other way around.

[navin]

There's something strange going on here.  An electric guitar with passive pickups has far less output than your acoustic with an active preamp in it.  The acoustic should sound louder than the electric.  Not the other way around.

Steven, thanks I was going nuts trying to duplicate that mellow sound. How do the Eagles do it? Does a PA have that much more control over tone than a combo?

ER, the Lead 12 had 2 inputs. The Hi input also did not have enough gain. Could it be an impedance mismatch? Would a D.I. Box like the LR Braggs help?

The Studio 15 is profiled here
http://www.thegearpage.net/board/showthread.php?t=1074289

The Lead 12 here
http://www.ultimate-guitar.com/reviews/guitar_amplifiers/marshall/lead_12_combo/index.html

Thanks everyone.

[srb]

There's something strange going on here.  An electric guitar with passive pickups has far less output than your acoustic with an active preamp in it.  The acoustic should sound louder than the electric.  Not the other way around.

That was my original though concerning the built-in preamp.  Just a thought - have you tried a fresh battery in it?
 
Steve

[Quiet Earth]

Hi navin,

Replace the battery in the Yamaha if it has one, or take the Yamaha down to your local guitar store and ask them if you can plug it into an acoustic amp to see if it is working properly. Then you will know if it is a guitar issue or an amp issue without spending any more money.

Keep in mind that even if you do get this sorted out, cranking up an acoustic guitar in a small room (or a big room) can lead to feedback issues, which is why your son's teacher may have recommended an acoustic amp in the first place. I like the little Fishman Loudbox Mini.

Here's something else to consider. If your son isn't performing in a band or playing acoustic anywhere outside of a bedroom sized room, tell him to play it unplugged. I think the best thing about owning an acoustic guitar is the ability to pick it up and play it just because it's sitting there.  If he only wants to play the acoustic guitar because it is plugged in, then he and you are just chasing gear.