The Amp Garage

Many of the Mesas I've seen use the same general signal path for distorted and clean tones, passing through several cascaded triode stages, compromising any chance at retaining a truly clean tone. Many of the Mesas I've seen are practically clones of popular "classic" amp designs, so it's no more a...

...bogner shiva ... Fuchs Mantis... Reeves space cowboy... also way nicer and easier to work on. Maybe they don't have the 50000 knobs and features the mesa has... You bet they don't. What you list are pretty much semi-dual channel amps with common tone controls so what's even the point of the exam...

I wonder... There's a common hate towards these things but they were still made for purpose, mainly to eliminate microphonics and to increase overall lifespan of devices while simultaneously reducing their power consumption and waste heat dissipation. At least the first characteristics doesn't seem ...

IMHO, the feedback loop is pretty much disabled when the output tubes are. So, like mentioned earlier, this suspiciously sounds like just disabling the power tube section (e.g. you can bias them to cutoff or just open the cathode circuit) and taking the signal from the PI. So, probably just a very "...

More modern solid state amp designs include protection circuits to shut things down as the loads get out of hand. On these amps, about all you can do is fuse the output and/or the power supply leading to it. And as all engineers know, power transistors always give their lives to protect the fuses. ...

Are any of schematics circulating in the Internet* "factory"? I doubt they are all entirely accurate. *There are two, one, "open loop" circuit with limiter control to "current starve" the phase inverter stage and reduce its headroom, and another, sans limiter but with a presence control, which evide...

Those are just plate dissipation ratings. How much will the plate dissipate when producing x watts of power will depend on design. Obviously you get rather different answers for A, B, C or D classes of operation.

If I understood correctly, the chip is practically just a precision rectifier and it forms a part of an envelope follower that tracks the audio signal. You can't drive the power supply voltage regulator directly with the envelope follower's output. ...or you can but then the circuit is nothing but a...

I'm quite sure they calculate potential voltage gain at 1 kHz. They might have even had a test input signal to scope against the output signal instead of relying on calculation. No, they don't consider non-linear operation. Pretty much the concept I have - in vain - tried to ardeously explain in sev...

It's good for selling stuff. if i pull up a decibel chart 110-120db is listed as rock concert/siren. so not knowing what they're actually saying, it tells your average joe "this thing is loud!" Decibel is basically just a shorthand for expressing figures with a lot of zeroes in them in a more simpl...

IMHO, very much the usual setup: Marshall 2203 with added gain stage at input and couple of other mods here and there to tinker the response and gain. 18k cold cathode bias on the 3rd stage is an intermediate between 2203's 10k and Soldano's 39k. (And yes, SLO is also a 2203 with input boost and few...

What makes you think that peak gain of tube amplifiers is much higher? Please, don't answer that HotBluesPlate said so. Do you have a statistical on this? Isn't a solid-state Ampeg VH-140C much gainier than a tube Magnatone 260 or do I just have clot ears? And do you think there is a difference if o...

Is amplification factor the ability of a sinewave to remain undistorted until it finally hit the headroom? Could amplification factor be the ratio by which the circuit/amp amplifies the input signal? Because it seems like the lower the input amplitude, the higher the output amplitude as long as the...

If you attempt to use a practical example vs a theoretical model, you’ll find that achieving 115dB gain is not possible. The input voltage from the instrument is going to place the amplifier in a situation where the input voltage can rise and the output voltage stops rising peak or rms. Well duh, w...

So would that be 36.1 dB max gain if the input amplitude is one microvolt? And is it still the same 36.1 dB max gain if the input amplitude is 10 volts?

Other than appealing to that HotBluePlates says so, why do you think something limits the total gain of multiple cascaded Metal Zones?