The Amp Garage

Thanks Martin, I will try that out over the weekend. Too bad I didn't see it sooner, I buttoned it up. Phil, I lent my 5F1 clone to a friend long term and I want to play some electric again, at home, not bug the neighbours, and unboxed my pedals. And I’ve been meaning to convert this to cathode bias...

You need to make a tube characteristics chart and plot the Vg1 lines on it (for the Vg2 voltage you are aiming at), That's asking a lot of me, especially as I'm in the dumbing epoch of my life :lol: I think if the Vp goes down the current goes up, so that's good. Can I just calculate the current ac...

Man, the voltages sure move around with the changes, I've been paralleling resistors and it's all 2X. I'm way out of my league here, I can just go by my ears. I'm not on that table anymore as the Vp is now 100v and I've no idea if I'm upping or dropping gain or have decent current draw for the pento...

What resistance are the plate and screen resistors? I understand the current is important to setting up a pentode right, but that's beyond me. Right now v1 is: Kr 2220k 25mf bypass 1.4V, 220K Plate 185v, 2.2M G2 with .05mf (to the cathode as Merlin says) at 35v. Next is to try a Kr of 1100, then a ...

That row that gives a VG of 192, with Ra of 470K is not good, too much dirty bassy drive and btw gave me a Vp 95v, I paralleled another 470K across it for 220K and it was much better sounding, Vp was now 185v. I will next try another 2200 across the Rk for 1100, then parallel the 2.2meg g2, which wo...

My thoughts are kind of, if your only going to use a mire 100 gain out of what a Pentode can offer, then why use it? I thought that too and why I asked, it is rock 'n' roll after all. I was hoping for specific guidance to values to use not as I'm too lazy to try things out but it's PTP and a PITA, ...

6sj7.jpg I'm going to try and set up the input pentode on my 5C1 clone to cathode bias to make it more pedal friendly. This is an operating conditions table from the actual data sheet. Seems they did the hard work of curve reading for you? Do I just pick an operating point - in this case Plate Volt...

Good to see everyone coming back to TAG. At least on Naim hifi gear I've been around and owned I can hear the filter caps start to go after 10 years, and they use very good filter caps and it's not anywhere near as hot in ss amps as tubes. I have a little 1980's Naim NAIT copy called an Onix that I ...

That amp makes me homesick.

You should not use solvent based contact adhesive on tolex. It'll soften and stretch and in time pull back and your corner cuts will show. Use something waterbased.

Sounds properly voxy. Turn the amp way up, guitar down, heavish strings, hit hard and you'll get the early Brit thing going. We were adrift at sea, wandering lost in the wilderness, exiled and condemned to wither and die. You have taken us in your lifeboat, brought us to the promised land. You are a...

I never played a tweed Bandmaster real or otherwise but I know enough to know it’s sui generis - tube rectifier, choke input power supply, under spec’d and mismatched OT, 3 x 10s, and of course the light baffle common to tweeds. Is this really scalable? That choke becomes at least 300mA maybe bigger...

I thought these laser etched types would be like the old Hiwatts, guess not. This was a helpful post. If I can ever teach myself f'!ng Inkscape I will order rear etched from Tube Town in Germany. Otherwise there's a nice old trophy shop in town, but he has a nice new 3D printer right in the window. ...

I agree. Engraved (milled or laser) faceplates are great but the materials can often lack durability. I will no longer do any plastic/engraved types. They are just not up to the task. Laser engraved metal stock is good but easily scratched. What fails? Does the laser engraving wear through, do they...

Prayers the exorcism succeeds.