The Amp Garage

Don't forget you need 10x power to double volume, which also means you need 1/10th power to half the volume. I don't think the power reduction will make much difference in volume. Both setups would be loud when pushed.

I'm a proponent for using run of the mill production tubes, especially for the power section, more so if the amp is hard on tubes. Instead, I'd do some mods to keep it from eating so many tubes. You can start with the 470 ohm screen grid resistors, I'd bump these up into the 1.5k-2.2k range. Unfortu...

Can't go wrong with an ODS, IMO, and since there's so many generations of those amps and differences between circuits it also doesn't hurt to have more than one ODS amp.

I would think those voltages will be way high for 6V6's. Maybe consider just modding the Bassman to have less headroom? Bias the PI like a Marshall, remove the NFB from the PI. Increase the midrange pot to 100kA and adjust the B+ dropping resistors to lower the preamp voltages a bit. Post PI MV. May...

3000pF/3nF vs 3300pF/3.3nF

Difference could be audible depending on how it's being utilized in the circuit, but neither one will make or break an amp, IMO.

I don't understand the tube power. I already use tube amps. All loaded, all sub-mixed, effected, and stereo to massive power and sixteen 12s. Slew matters for impact and clarity. The extra tube output is actually anything but transparent at unity. I admit that the device makes me angry. lol For ins...

This thing wants to run hot. with 120VAC line, the plate V is 455, when tubes are idling 26/30 mA with bias V -50.8V. With the price of tubes throught the roof these days, I'd really like to make them last. Is there a relatively painless way to lower B+ down some? Just use JJ's. Datasheets spec the...

Here is a pdf and link to various articles and tests regarding different dielectrics vs voltage stress on capacitors. CC are known to have a higher voltage coefficient, and some people point to that and say they will add sweet-sounding second harmonic (thanks, RG), but IMO it's negligible. I tried ...

This is one of my favorite pics to demonstrate measurable differences exist between different dielectrics. Now, the hard part is quantifying that, and translating to how it will sound in a guitar amp. It's clear that one of these caps is superior if you're going for minimum THD, for something like H...

EL34's should be good to 800VDC on the plates and 500VDC on the screens if they meet datasheet spec (which any decent quality tube should be able to meet.)

The 400VDC coupling caps in the PI are a bad idea. Mesas fail all the time because of this. 630VDC will be better. It's because the -bias voltage is cumulative with the positive plate voltage. The cap 'sees' both these voltages added together. So if we had a -50VDC bias voltage and a 250VDC plate vo...

Not only do you want the Zeners on the input, but, IMO, you also want a coupling cap on the input to block DC in either direction. This will protect the MOSFET as well as the player, in the event the LND150 shorts, it's possible to get DC from the B+ line on the tip of the input jack.

Oh yay. More $14-$25 coupling caps that'll definitely sound better than the $0.15 cent films you can get off Mouser :roll: I'd maybe consider using them for repairs if the customer wants to keep the aesthetics, and doesn't mind overpaying for caps. I can't ever see myself doing a build with these, u...

for any output tube cathode follower directly coupled, +150 -100V will be enough blind guess, also mosfet can easily work there But with the MOSFET, you won't get the unique DC coupled CF 'distortion' achievable with the tube. In some cases that may be desirable, but it's worth noting. A note about...

some people hear differences some not. That depends on the listener... As you wrote, "its a hard yes or no for one or the other". But that does not mean good or bad over all. To finish the build lgehrig4 can use any suuitable capacitor and it will sound fine. When the types he really like to use ar...