The Amp Garage

Put another way, it seems that because the positive and negative ends of each plug are connecting to the same point at the transformer secondary, then there isn't a parallel connection.

I’m going to pull the inner two 6L6 power tubes from my Twin Reverb and I’m trying to figure out a way that I might still use the two 8 ohm speakers in the combo cabinet to arrive at a final speaker load of 8 ohms. My understanding is that when both the Speaker and Ext. Speaker connections are used ...

If I understand correctly, if I wanted to increases sag in the ultralinear portion of the amp, I would increase the 470 1W screen resistors as shown in the attached 135 watt ultralinear twin reverb schematic. I suppose logically there must be some sag on the portion of the signal being fed back into...

Tone King's description of their Sky King amp states: "Selectable pentode (tighter), ultralinear (added sag) operation modes" I can't find any info elsewhere regarding how ultalinear output amps might impact sag. Is there a difference in sag with an ultralinear output, or is this a misnomer on Tone ...

Yes, I already bought them. I think they were a little more than Solens, but I especially like the shape. It's going to be a project just to get everything to fit - here's a photo of five in the cap cover. Hopefully, they reflect quality German engineering :D [attachment=0]Mundorf Tubecaps in Pan.jp...

No, not more things to consider... I'll be using Mundorf Tubecap capacitors. Their description doesn't specifically mention ripple current - hopefully their description of "self-healing properties" is related to ripple current: The TubeCap® is made of polyprophylene film with special features. This ...

Thanks all for your help. I just now saw some messages for the first time. I’ve attached a photo of power section of [attachment=0]6L6GC schematic - power section.jpeg[/attachment]my current schematic. I just purchased some vintage RCA 5R4GYB tubes with the thought of having a back-up. I currently h...

R.G. The data sheet(s) don't include hours or life expectancy. In my quest for a greater understanding, I found an old article online that discussed another unrelated valve, and there was a comment that the data sheet ratings were applicable to the life expectancy of 5,000 - 10,000 hours. Of course,...

Thanks. My question is probably more difficult to answer than it would have been 70 years ago when there were people still around that performed the testing and contributed to the data sheet. I don't know the specifics of how the 20uf figure for a filter input capacitor was arrived at. If it was fro...

The 5R4GYB data sheet shows a maximum of 20uf for the filter input capacitor. I’m hoping to use 30uf as the filter input capacitor, and I’m wondering if the 20uf rating was obtained under conditions that my amplifier won’t see, specifically 40,000 ft elevation and 900v as is shown in the data sheet....

Slucky, Your schematic helped me in a practical sense with my current project. Your amp is first one that I’ve seen with the parallel preamps - I’ve had that same idea for years. Too much for me to pull off at this time…but with this schematic I’ll be very tempted. It seems like it would provide tre...

ViperDoc, Thanks for covering many bases there. If I understand correctly, if I added a fuse on the HOT 120V PT Primary winding there would then be a fuse both before and after the main power switch. Ten Over, Thanks for the schematic. I see the capacitors are bumped-up and it looks like you made so...

Hello, I'm in the planning stage of building an amp with the foundation being the 5F6-A. I've got a great power transformer that I'm going to use, however it doesn't have a bias supply tap. I have Merlin's book on both preamps and power supplies, but I'm still struggling to understand the precise st...

This chassis fits the cabinet, so I expect to use it. The photo of completee chassis gives me inspiration - that's the route I'll take. Thank you.

Hey everyone, it's been a while since I tried to build an amp, but I've made a New Year's resolution to build one in 2024. A number of years ago, I purchased a new 1 x 12 combo amp cabinet and empty chassis from S2 Amps - a circuit board wasn't included. I think S2 used this combo for a 6V6 Deluxe v...