I’ve not been updating this blog for a while now, life really got in the way. That doesn’t mean I haven’t been busy, and here is one amp I did a transformer swap on…
(this picture is from the net, I forgot to take one of the whole amp…)
There is a common mod to do to the later models of this amp, which really opens up the low-end. It’s basically just snipping out a tone-network and changing one coupling cap.continue reading
Cool, no? Half power switch… 50 and 25.. watts?? From a pair of 6L6’s in cathode bias with tube rectifier.. with a Hammond 290BEX PT… really???
eh,, I measured it to a meager 12-15 watts in the 50 position… and all is working correct inside… Does sound good thou!
As if hauling around a standard twin was not enough fun!continue reading
Two quick fixes….continue reading
Just a quick post, this one came in for service yesterday…
Just needed a new tapeloop, cleaning of pots and connectors and it’s running fine… Space out!
Love that Sound-on-Sound effect!continue reading
Husker du det vakre 50-tallet? Remember the great 50’s? This one does!
A very nice Combo this, it’s got 2x 6V6 cathode biased output, 5Y3 rectifier, 3x 12AX7 and a 12AU7. 2 Channels, mixing happens like in a 5E3 circuit. This amp has got a really sweet vibrato circuit, employing varistors to do it’s trick. Good’ol’ GE tubes all over! All in all this amp sounds REALLY good, both clean and when breaking up. Fender, go home!
Really simple inside, point to point wiring.
We are going to swap out the power transformer for one that can run on the local 230 volts utility.
The replacement trafo has no mounting for standing up, so we will take the endbells of the old one and put on the new one. Gonna look better too!
Voilla, ready to mount!
All wired up. The bias tap goes unused. Also this transformer does not have a centertap on the heater winding, so we will make an artificial one with 2x 100ohms resistors to the cathodes of the output stage (elevated heaters, like original).
We will swap out the multi-can-capacitor as well, it’s pretty tired, 2 of 4 sections measure quite bad.
Schematic. Notice how the PI is gridleak biased…!continue reading
Today a cool little powered mixer from Yamaha! These are cheap on Ebay!
4 channels, got built-in reverb, echo send/return, monitor mix and stereo 2x 30W power outputs.
Plenty of taps on the transformer, so this one got reconnected from 120 volts to 230 volts.
One of those poweramp modules is dead, got a new one from ebay,
should be coming in a week or two….
Wow, sometimes ChinaPost is really fast! This dropped into the mailbox just now! Stuck it in there and now all is swell in stereo!
The mic preamps have transformer balancing, and it turns out they saturate a guitar quite nicely when driven from the echo-send with a jack-XLR cable.continue reading