5B6 started

[Blackburn]

Dude! I love that thing!!!

I think what you did to the tweed is sweeeeet!

[M Fowler]

I hope your Bassman gets working great because it would be a shame not to be able to enjoy your fantastic looking combo.

Mark

[Blackburn]

Man, I'm itching to do another 5B6... Real bad.

Hopefully by the end of the year.

[telentubes]

Still tweaking. This amp is taking forever to dial in but it seems worth it as it has some nice tones. I'm stubbornly determined at this point. I am currently using a Weber solid state rectifier which has lowered the voltages closer to spec. First stage couplers lowered to .02. V1 plate is 180K. V2 plates are 240K but still need some adjusting. I'm trying the lower Fender spec voltages on V2 which seems to help the flabby bass. I want to try running two caps in series for the first filter stage because start-up spikes over 500V. Etc. Etc., but it's getting there. I need to tighten up the bass and dial out some treble.

[M Fowler]

It's really strange for myself as well because my first build has no low bass flab and I kept it stock to Tino's schematic.

My third attempt is not anywhere near the tone quality of the first 5b6. Maybe because it is not PTP, not the same components and I used Fender replacement transformers.

I then changed it to more of a Ampeg B15N with 6SL7 tubes instead of 6SC7 preamp. Running 6550's. Now I'm tracking down a hum? I need to stop this madness.

Mark

[Blackburn]

Me too, Mark. I didn't stray very far at all from the Tino schem. I think the NF resistor was something like double the stock value, but everthing else was stock, except the first pair of couplers. I went with .02uf and stayed with .1uf for the PI. I'll also need to get a cooler PT than last time. That, and a different choice of certain materials from last time should make me fall in love with the thing like you're talking about.

[M Fowler]

I used the .1 caps throughout and changed the 25uf/25v 6L6's bias bypass cap to 220uf/63v.

The amp has this fantastic tone and almost reverb like quality. Not sure if Rodger (owner) has recorded the amp or not but he would be playing a pedal steel if he did. I know he spent some time finding the best NOS tubes.

The amp was better then a Little Walter 50w and the other amp tested against it was Tim's Milkman 85w which is an outstanding amp, totally unfair to use that against my cage amp

[Blackburn]

Very cool, Mark. I totally know what you mean about the airy reverb quality. I noticed the same thing when mine was kicking. Although, I did the opposite with cathode bypass caps (Stock, I guess). I used a 220uf BlackGate to bypass the 6SC7 and kept a 25uf/50v Sprague for the 6L6s. One thing that made mine was using the RCA 6L6GC Blackplates from my organ. I even used the 5U4 from the organ. I'm planning this one out again, using old ABs and maybe a 6SL7 in the front instead... Maybe. I did like it stock, though.

[Matt D]

I want to revisit the 5B6 and do it EXACTLY to Tino-Z specs with the Weber iron Mark used. I think my chassis and iron were too big.

[telentubes]

Waiting for parts again, and still tweaking. Thinking about that too Matt. Might just move on to something else.

[M Fowler]

Yup start with a Watt's 12x8x2.5 chassis and bottom plate then get a Hammond cage top no need for expensive wood cabinet. Put a bolt through the rubber feet and use the feet to bolt the bottom plate to chassis and your done.

All PTP in a nice small package.

I put a metal handle from Menard's on lighter end of the chassis easier to carry that way. Cage top is too light to be using a handle on.

Mark

[tictac]

I just finished a 5B6 type amp myself... The only change in the original circuit I made was the tone control. The stock TC was rather underwhelming for guitar. I replaced it with the tone circuit seen in some of the Matchless amps like the Lightning model. It's a treble bleed like the 5B6 TC but adds a bright cap to the circuit.

I really like it; has a very smooth subtle transition from bass to treble without getting too muddy or too bright. Really help this circuit to be compatable with a guitar if that's what you're using it for...

Only other wrinkle in my build was to use some Solen filter cap I had laying around. Darn things sure do take up alot of room; and I used a small chassis too. Really had to cram stuff in there...

TT

[M Fowler]

I added a bright switch to the 5b6 cage amp before I shipped it out.

You wouldn't think a rat's nest like that would be any good at all, but we miss this amp.

[telentubes]

Got more parts today so I'll go back in. I'm intrigued by the Lightening tone stack, which I might try if this next stage proves fruitless. Hey wait! How bout using it as a bass amp?

[Blackburn]

I actually didn't mind the stock tone pot when mine was kicking. Simple, but worked for me!