Recent content by slavax

Haven't been on this thread for awhile but I did use my B-15 creation on a blues band pickup gig back in March. It sounded really good although I couldn't bring the volume up much w/o starting to get some distortion on the E string but since it was miked it wasn't a problem. Using the bright...

Did the .1 mfd cathode bypass on V1 A; the bright switch and brought the plate voltage down with the Vintage AC box. This past Fri. I rerouted some ground wires to fix a parasitic oscillation. So the beast is in pretty good shape although not quiet enough for studio work.

Update: I did some ear testing on the amp and have decided to take the two 120K resistors off the SPDT switch in the zugster tone- stack mod and make it a bright switch w/ a 250 pf cap (I will hard wire the one 120K resistor remaining.) Also I'm going to put in a .1 mfd cathode bypass cap...

BTW- thanks again to Vintage Blue, BOT, Jimmy M and Bassman Paul for helping make this thing happen. It's been a long time coming but I'm almost there.

OK- thanks! I guess I need to go back and trace the circuit, etc.

Hey you all: I've finally got my B15 NF project done except for some little cosmetic touch ups. It's sounding great! But I've got a question for anybody out there that has a mid- 60's B15 w/o a bright switch: does the treble knob make much difference in the sound? Working the...

Welp, I'm working on the brain to put the chassis, etc. in. I thought of something else that I changed up from the original B15 NF schematic: I rewired the standby switch a' la Fender. I didn't like how the signal bleeds through on standby in the Ampeg standby scheme.

BOT: Thanks for the info!

Hey- I know this is off the topic of the thread right now but is there someone out there who has a Portaflex B15 NF that can tell me what the info is on the back panel about how much juice the thing draws in volt and amps? Thanks

Hey Guys: I was wondering if someone out there who has a B15 NF (#2- 6L6 power tubes) could tell me what the info is on the back of the head about how much juice it draws in volts and amps. Thanks

Yeah, our line voltage gets up to around 121-122. I've looked at the Weber kits nut I'm so tight on space I don't think I've got a good, safe place to stick it. I'm think the Geofex Vintage Voltage is the way to go. Long story short: I should have tested the transformer before I started...

I did use the 5AR4 in it at first but my plate voltages were way too high - like 520 V. A friend suggested putting in the 5U4GB to drop the power supply voltage. (I've got a Leslie cabinet that uses them.) The 5AR4 drops about 17 V and the 5U4GB drops about 50- 55V. I believe the 5AR4 is...

Details on my B15 project: Only one channel Added a Fender- style bias adjust knob " bias check resistors " a variable negative feedback knob " a Baxandall James stack w/ frequency shift (zugster link earlier in this thead.) Made a solid- state plug- in rectifier but...

Gee- I wished I had seen that notice about Sovtek 6SL7's about 2 wks. ago: I bought some and they hum! I guess I could use one in the PI but meanwhile the NOS are working just fine. I bought a Sovtek 5Y3 a few years ago and later found out that they were another tube type that had been re...

mccracer: Yes, I'm still working on the amp but the project's had to go on the backburner numerous times the past 2 yrs. But last Sat. I finished the double baffle cab and loaded the JBL D130 that I reconed into it and tried it out for the first time w/ a bass guitar and it sounds kick...