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indianjjy
August 5th, 2008, 07:54 AM
I just picked up one of these the other day. Does anyone have any info on it? It is never been used, early 70's I would imagine. Any info would be appreciated...

tunghaichuan
August 30th, 2008, 01:03 PM
Just saw this.

I believe I have a hand-drawn schematic somewhere. I have a couple of NOS OTs.

It is basically a champ with a Baxandall tone stack. It was made by Dennis Kager of Sundown amps in the early 80s. I've never seen one in person, though.

I believe Dennis still repairs at Central Jersey Music Services in Edison, NJ.

tung


I just picked up one of these the other day. Does anyone have any info on it? It is never been used, early 70's I would imagine. Any info would be appreciated...

Slimster22
March 12th, 2010, 08:20 AM
Hey, I came across the old post about possibly having a hand drawn schematic for the Sundown Rocky amp. I could greatly benefit from one of these. Is there anyway I could get a copy of it from you? Thanks.

funderbunk
December 8th, 2010, 02:54 PM
Hey all, I know it's not great form to bump such an old thread, but I just got one of these little beasts, and there is precious little information out there about them.

Mine has seen better days - the amp itself is in pretty good shape, but the cabinet is about to fall apart. I'm thinking if I have to make a new cabinet, I'd like to make it a head. What I could use is some information about the output transformer - I'd prefer to replace it with one that has 4/8/16 ohm taps.

tunghaichuan
December 8th, 2010, 06:48 PM
Hey all, I know it's not great form to bump such an old thread, but I just got one of these little beasts, and there is precious little information out there about them.

Mine has seen better days - the amp itself is in pretty good shape, but the cabinet is about to fall apart. I'm thinking if I have to make a new cabinet, I'd like to make it a head. What I could use is some information about the output transformer - I'd prefer to replace it with one that has 4/8/16 ohm taps.

I never did find the schematic. :(

The OT is 5K:8ohms, single ended probably good for no more than 5-7W. It's a little bigger than a stock Champ OT. The Hammond 125CSE would probably be a good replacement. For an upgrade, one of David Allen's OTs (http://www.allenamps.com/parts.php#transformers) would probably sound better. The TO10B would probably be the closest to the stock OT. The Allen OT has 4/8/16 ohm secondaries as well.

funderbunk
December 8th, 2010, 08:44 PM
Ah, thanks for the info! Fortunately, the little bugger seems to be working just fine, other than the fact that the particleboard is about to crumble apart - I think in spots it may be being held together by the tolex. :thwap

I was a bit concerned that the particleboard issues were due to moisture, but taking a look inside it's surprisingly clean with no signs of rust or other damage. And considering what it's putting out, it is quite a loud beastie that sounds pretty darn good.

Like I said before, there is precious little info out there about these, but one thing I did read was that they were somewhat notorious for blowing their output transformer, so it's good to know some details on that.

I was considering using one of these as a replacement:

http://store.triodestore.com/40-18031.html

I was thinking it might provide a bit more breathing room; any thoughts?

tunghaichuan
December 9th, 2010, 09:46 AM
FWIW, the amp is basically a champ style amp with a Baxandall tone control, IIRC. It wouldn't be too hard to trace out the schematic should you need to.

The triode OT is probably adequate for the job, and it is priced right. The stock OT is a bit bigger than a normal Champ OT, so you may have to drill another hole to mount the Triode OT.

And yes, I've heard the rumors of Rocky OTs blowing as well. The stock OT doesn't look very sturdy, which is why I haven't used one to build an amp.

As far as the cab goes, you might be able to find a woodworker who would build you a nice plywood or even hardwood replacement cabinet.


Ah, thanks for the info! Fortunately, the little bugger seems to be working just fine, other than the fact that the particleboard is about to crumble apart - I think in spots it may be being held together by the tolex. :thwap

I was a bit concerned that the particleboard issues were due to moisture, but taking a look inside it's surprisingly clean with no signs of rust or other damage. And considering what it's putting out, it is quite a loud beastie that sounds pretty darn good.

Like I said before, there is precious little info out there about these, but one thing I did read was that they were somewhat notorious for blowing their output transformer, so it's good to know some details on that.

I was considering using one of these as a replacement:

http://store.triodestore.com/40-18031.html

I was thinking it might provide a bit more breathing room; any thoughts?