slider313 Posted August 4, 2013 Posted August 4, 2013 I plugged into one of these, at a used guitar and amp shop back in NY about 15 years ago, and never forgot the big, beautiful cleans it had. I couldn't afford it at the time as this shop always marked things up higher than most. You don't see them very often but I just happened to catch one for sale on TGP last week. I really don't need another amp but this 35 watt, 2x12, cathode biased, 7027a powered amp is just one I couldn't pass up. It dates to 1961 and has a pair of alnico Jensen P12P speakers will bell covers. It should be here this Tuesday, if the FedEx tracking system is correct. I'll give it a good going over; a three prong power cord, new electrolytic caps, checking all resistors to be sure they're in spec, cleaning the pots, switches and tube sockets. Even though this amp uses 7027's, it has low enough plate voltage and is cathode biased so, it can also run 6L6GC's, 7581's and 5881's. I see some "tube rolling" in my future! Pictures and tone report to follow.
Blunote Posted August 4, 2013 Posted August 4, 2013 I'll look forward to it. Found this on YT Apparently they are Gretch branded Valcos. Valco built amps that were variously branded. A really cool vintage vibe. Really, it's own thing.
slider313 Posted August 4, 2013 Author Posted August 4, 2013 Yeah, Valco built amps under many different names. I saw a few youtube videos of the amp, most by the same person, and I think that amp sounds a bit thin and probably needs a little TLC. http://www.valcopages.com/WhatWas.html
slider313 Posted August 9, 2013 Author Posted August 9, 2013 Well it got here in, pretty much, one piece. RCA tubes throughout. The power tubes and rectifier are shot but only one of the six 12ax7's was bad. One of the speakers is buzzing and "flapping" on the bass notes. Upon further inspection, the cone separated from the frame around the rim. The bias caps and a power supply cap had the negative connections broken. I guess this happened in shipping as the seller stated it worked and sounded great. The speakers are on their way to Weber for re-coning. The electrolytic caps have been updated and all sockets, switches and pots have been cleaned. I replaced the two Jensen P12P's with an Oxford and a Jensen for now. The amp sounds good but there's a resistor making some slight noise. Probably a 100k plate load resistor on one of the pre-amp tubes. Valco made amps are real tough to work on as there are rows of terminal strips, sometimes three or four deep, riveted to the chassis. A real steady hand is needed for de-soldering and replacing components on these amps. I guess I'll wait until the speakers come back before I crack it open again. It sounds very similar to a low powered tweed Twin, so I'm more than happy!
SouthpawGuy Posted August 9, 2013 Posted August 9, 2013 Cool looking amp, what are the switches for on the rear ?
slider313 Posted August 9, 2013 Author Posted August 9, 2013 Cool looking amp, what are the switches for on the rear ? Thanks SG. The middle one is a tuner; turn it on and the pitch (now a "D") can be heard. You can set it to different notes. The one on the right, under the fuse cap is the on/off, the one across from it on the left is the standby and the one above that is the bright switch. The volume knobs are pointed shaped ones and the bass and treble knobs are the round ones. Right now I have a set of GE 7581A's in it. It sounds good with the newer Tung Sol 6L6GC STR's also.
SouthpawGuy Posted August 9, 2013 Posted August 9, 2013 A '60s amp with a built in tuning reference, never heard of that before.
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