Greetings, and looking for advice for an amp module

[mixsit]

Hello everyone. My first post here, and I hope I've come to the right place.
I'm a long time musician, and have about 20 years in with a part time home studio.
My project here isn't exactly DIY.. More 'Assemble It Yourself perhaps.

I have a Pearce G2x preamp that was part of my rig along with the G2R head back when and I want to commission an open back combo' cab for it. I'm looking light preconfigured plug-in 120vac' SS power amp module to mount in the back.

I'm not looking to build a real high power rig, 1-10 or 12 inch, but given the light high efficiency amps available presumably I'd want to land on 'more than enough than come up short.
I also don't know whether I need to be concerned about the power amp's tone? The Pearce (in the G2R config at least) does real well in that regard, but this is new territory for me here.
So, Hello again. And thank you for any help and guidance.
Wayne

[J M Fahey]

A Pearce? Wow!!
They are famous/mysterious amps around here, specially for SSGuitar type guys.
Would please share something of them with us?
Schematic (if available), user manual, a couple pictures (guts preferred), whatever you can.
As of what you need, it's quite possible.
The amp itself does not need "a tone of its own", but rather reliably amplify whatever is fed to it.
A single LM3886 will give you reliable 50W; two of them will provide twice as much, with practically the same size and weight considering the total system.
2 good 10" or 12" guitar speakers (Jensen, Eminence or Celestion) will fill the bill for a very reasonable price.
How do you see yourself building a nice simple cabinet?
Or you can get it ready made.
What about your soldering/mounting skills?
You can mount your power amp and PSU in the back of the speaker box, with only a power cable, switch and input jack(s) showing, together with a master volume if you wish so.
Ok, ok, also a power Led and a Fuse holder. Big deal.
You can mount it in a couple weekends, and enjoy it all the way.
You are certainly in the right Forum.

[mixsit]

Well I went through all my Pearce docs and they have block diagrams but no schematics.  I could open them up and take pictures, scan the manual(?) if you feel it would be useful.

What about your soldering/mounting skills?
You can mount your power amp and PSU in the back of the speaker box, with only a power cable, switch and input jack(s) showing, together with a master volume if you wish so. ...

Yes, I have the skills, done a few Haffler kits along the way, good with tools and such but you see I'm not quite going into that mode. I'm searching for a small power amp package, and just been surprised to find how few have come up.. Likely I haven't looked in the right places.
Ironically, I was checking out one of my wife's bass amps- A GK MB200- It'd make for a tight fit (don't need tone controls), but 2lbs.. and I wonder if the price even can be beat.
http://www.gallien-krueger.com/products_mb.html
Found these guys.. No prices yet.
http://www.amplifier.co.uk/images/SDV1035_100_A_EU.pdf

[joecool85]

I'm sure all of us would enjoy a scanned copy of the manual as well as maybe some pics of the amp itself.

[J M Fahey]

If you can mount one of those amps into a cabinet and use it as a powered box, fine.
Only thing that worries me somewhat is that it's specified *only* for 5 minutes continuous full power.
Fine for an audiophile listening to a Symphony at home; useless for a Rock Musician, even if playing in the basement.

[bry melvin]

http://www.carvinguitars.com/products/single.php?product=DCM200L


ultra light  power amp

[mixsit]

If you can mount one of those amps into a cabinet and use it as a powered box, fine.
Only thing that worries me somewhat is that it's specified *only* for 5 minutes continuous full power.
Fine for an audiophile listening to a Symphony at home; useless for a Rock Musician, even if playing in the basement.

Thank you for pointing that out, I didn't read if carefully before.
Here's the 7lb Peavey.. It's mostly box
http://www.talkbass.com/forum/f15/peavey-ipr-1600-internal-photos-617982/
But it's still large for a combo amp, and a kludge even if I wanted to go there.
What are the manufactures doing then in these inexpensive medium power combos? A fan and the whole chasis is the heat sink?

[J M Fahey]

A fan and the whole chasis is the heat sink?

Personal experience with aluminum chassis:
60 to 100W amp: 2mm aluminum backpanel , vertical, 4" high by 17" wide, transistors bolted directly to it or through an L shaped aluminum bracket.
200W: same thing plus 8" worthof finned heatsink for passive cooling or cabinet side mounted 12V PC fan blowing across and around it .
300W: PC fan as above.
Higher than that require building a "cooling tunnel" with long heatsinks, fins pointing inside , the fan mounted in one end blowing into it and transistors mounted on the outside.
Even on the less than 200W class, a fan never hurts, but you must plan for the cooling air path.
Powered monitors try to avoid fans (because they are sealed and very compact) by bolting a very large heat sink assembly on the back, and using class D or H power amps for lower heat to begin with.
But if you build an open back box (think a Twin) you can easily mount any amp on its bottom inside, and it will be essentially in free air.