Tube Amp Archive

I also have a JBC for around 10 years now. Phenomenal! The tips heat up in 6 seconds to full heat, when in the stand it cools down to prevent grilling the tip and when you pick it up, it reheats in 3 seconds. strong recommendation!

It’s a fair point, I used awful solder on this project. But however I will be rebuilding it at some stage. The idea is to get it working first With all due respect: Working sloppy and expecting to get it working before you correct your mistakes is begging for trouble and repels those who are willin...

I know this guy personally. A retired University professor for acoustics and signal processing. He wrote the, to my knowledge, single book about the physics of the electric guitar. He knows the stuff inside out. Wrong adress if you believe in mojo. Difficult personality though...

the configuration at V1 also allows to make the left capacitor switchable to alter the frequency response of the first stage. You can populate the resistor to take tha cap out in normal operation and a switch can bridge the resistor to make the capacitor effective. Thus, depending on the capacitor v...

Hi Lycoming360,

did you finish your project? I'm considering to build a similar one to the one you described,,,
I am curious about the outcome, esp. the 6V6 power amp.

BR
Robert

same problem over here in Germany, but still get to the forum after the error message

Hi Vorg, chokes are used to filter ripple in the power supply which only should occur in AC supplies. When talkin about pedals you usually have a DC supply which comes already filtered (best case, there are bad DC supplies...). In tube pedals you usually have a normal low voltage DC supply which get...

Tube-Town themselves is the best resource to answer this question

RG wrote a great article on resistors and their sound/noise and where to use and where not
http://www.geofex.com/ search for "Using the Carbon Comp Resistor for Magic Mojo" on the starting page

or use painter's pyramids

the DR reverb has trannies that are undersized for the circuit by design, esp. the PT this leads to sag and compression which makes an important part of the DR's sound and feel if you build it with way oversized trannies, you will lose that. The preamp should be probably quite similar between a DR a...

I would stay away from OSB. Marshall used it for some time but the cabinets are desintegrating with vibration over time (keep a vacuum cleaner handy) MDF is heavy as lead and does not withstand stress on the edges very well almost everybody uses 18mm/1/2" plywood today, if reinforced, you might get ...

in my designs I used both approaches and never had a hum issue. Lately I stick to Merlin's approach using the gap between Pin 1 and 9 make sure that other wires have a good clearance to the heater wiresand if necessary at all, let them cross in 90° angle or loop them over the socket. I prefer loopin...

most multimeters have problems measuring small resistances exactly... If you don't have access to a trusted one, maybe comparing measurements from different multimeters give you a feeling of how far your multimeter(s) is/are off I know, this is not a solution but shows if your eqipment is the proble...

Merlin Blencowe offers a ton of understandable documentation here. see http://www.valvewizard.co.uk/localfeedback.html for calculating feedback and frequency response see http://www.valvewizard.co.uk/OtherStuff.html for capacitor values and effect on the frequency response of a gain stage. Both 47µ ...