Kt66 for dirty shirley?

[fusedbrain]

re: tubes for the Dirty Shirley - Dave has stated on this forum at least once that he voiced the whole amp around the Sovtek 5881's.
Those tubes are tough as nails and sound great! I wouldn't bother with anything else personally.
I would also avoid KT66's in this amp due to the stock screen resistors being 470 ohms and KT66's like to see 1k, and the primary impedance of the output transformer is too low to get the best out of KT66's.

For pre amp tubes it's the same deal. Dave and most other builders are voicing their amps around current production tubes. Save the NOS glass for the vintage amps ( and save yourself the $$ )
The stock ARS tubes are likely JJ or Chinese, and might even be a JJ in V1 and Chinese for V2 & V3.( which is how my BE100 shipped )
The JJ's are a touch darker and smoother and the Chinese B's are a bit brighter.

My favourite combo for Marshall style builds is a JJ in V1, a Tubestore preferred series 7025 in V2, and a Sovtek LPS for the phase inverter.
I get all my tubes here:
https://www.thetubestore.com/
These guys are the real deal and stand behind everything they sell. Highly recommended

 

[fusedbrain]

I should also mention that it should be pretty simple to tell what the ARS 12ax7's in your amp actually are. The JJ and Chinese tubes have very distinctive plate structures that are instantly recognizable and unique to each manufacturer. If your ARS tubes look like either of these, then that's what they are.

Note the vertical bar in the plate structure behind the lower left "J" in the logo


Note the chrome coloured metal structure on the right in the Chinese tube.

 

[Chance terrill]

Then I would say jj ecc83s (I have one that I held up to the v1 stock tube in my shirley and they look identical) in the v1. And those silver dragons in v2 and v3. I also have a long plate jj ecc803s, would that be a good pi tube? I heard the long plates are more microphonic which I don't want in my v1 n since I think the Shirley is a cascaded gain circuit I don't want that in the v2 either.... But I heard. Jjs long plates are good reliable phase inverters

 

[CornNutz]

I would also avoid KT66's in this amp due to the stock screen resistors being 470 ohms and KT66's like to see 1k, and the primary impedance of the output transformer is too low to get the best out of KT66's.

His screens are 1k, its a newer DS with the PCB, it can run el34's if he want's. But I agree the 5881's are good, and what it's voiced around.

 

[Chance terrill]

Man learning about this stuff is addictive.... Thanks for the help guys

 

[fusedbrain]

Then I would say jj ecc83s (I have one that I held up to the v1 stock tube in my shirley and they look identical) in the v1. And those silver dragons in v2 and v3. I also have a long plate jj ecc803s, would that be a good pi tube? I heard the long plates are more microphonic which I don't want in my v1 n since I think the Shirley is a cascaded gain circuit I don't want that in the v2 either.... But I heard. Jjs long plates are good reliable phase inverters

Yes, the JJ long plate could be used as a phase inverter tube.

 

[fusedbrain]

I would also avoid KT66's in this amp due to the stock screen resistors being 470 ohms and KT66's like to see 1k, and the primary impedance of the output transformer is too low to get the best out of KT66's.

His screens are 1k, its a newer DS with the PCB, it can run el34's if he want's. But I agree the 5881's are good, and what it's voiced around.

OK cool. I've only been inside 2 older DS amps to add structure switches. Both amps were built on a red turret board, and both those amps had 470ohm screen grids. One came in with Mesa 6L6's, but left with wafer-based 5881's. Sounded exponentially better with the 5881's
Both those amps sounded f'n fantastic. Killer amps

 

[Chance terrill]

It's not quite pcb..... It's a hybrid eyelit board, flying leads etc..... I was told it's quite different from regular pcb like in the runt..... Obviously the pots and sockets are hand wired chassis mounted but Dave told me something about theres only a few Traces for dc heaters and something else I'm not sure what that even means just that he told me it's not all pcb

 

[CornNutz]

It's not quite pcb..... It's a hybrid eyelit board, flying leads etc..... I was told it's quite different from regular pcb like in the runt..... Obviously the pots and sockets are hand wired chassis mounted but Dave told me something about theres only a few Traces for dc heaters and something else I'm not sure what that even means just that he told me it's not all pcb

We'll technically it is a PCB, because it is a Printed Circuit Board. However it is built in a way that It has large plated through via's that work like eyelet's, and the board is thick. I agree, he can call it a hybrid, it is a superior design compared to your standard PCB. I like it.

I've worked on his amps with these boards, and it's just as good as working on a turret, or eyelet board. however the lead free solder is a pain in the ass.

Now one grip, he has switch to radial filter caps, which is good, however you will have to remove the board to service them. I would have layed them down so that the leads are exposed on the top, then used glue or zip ties to hold them to the board.

 

[Chance terrill]

So on a turret board the caps and shit like the mustard caps and resistors Etc are wired to turrets and soldered then actual wires come off the turrets and go to their destinations like pots tube sockets Transformers Etc correct? Where as this new Friedman method the caps resistors Etc go in 2 these Vias you talk about, or eyelets, or whatever they are, then what happens? does a wire meet it on the other side of that eyelet? Or does that eyelet connect to a Trace and if so where does the trace turn into the wire that goes to the pots and Tube sockets?

 

[Chance terrill]

Also are you guys famous amp builders too? May be a dumb question but u guys sure know a shit load about amps...... I'm a sub contractor so I do framing siding bathroom remodels roof repairs chimney flashing Etc but in the winter it can get a little slow and I would love to start tinkering with amps on the side obviously id have to learn a lot more, how do you learn more about it? Just messing around with your own stuff? I live in Ohio and there's only like two amp techs in a 200 mile radius so it would be neat if I could bias people's amps and do power tube swaps, things like that on the side, hell even to just do it for friends would be cool

 

[CornNutz]

So on a turret board the caps and shit like the mustard caps and resistors Etc are wired to turrets and soldered then actual wires come off the turrets and go to their destinations like pots tube sockets Transformers Etc correct?

Yes, for the most part. However some spots can/will connect directly to other components on the turret, and you usually have some jumper wires that make up the B+, and/or a ground buss on the board.

Where as this new Friedman method the caps resistors Etc go in 2 these Vias you talk about, or eyelets, or whatever they are, then what happens? does a wire meet it on the other side of that eyelet? Or does that eyelet connect to a Trace and if so where does the trace turn into the wire that goes to the pots and Tube sockets?

Dave's hybrid boards work about the same as stated above, but it uses a few PCB traces for the B+ buss, and ground plane. Also has spots for relays, and the relay traces.

Also are you guys famous amp builders too? May be a dumb question but u guys sure know a shit load about amps...... I'm a sub contractor so I do framing siding bathroom remodels roof repairs chimney flashing Etc but in the winter it can get a little slow and I would love to start tinkering with amps on the side obviously id have to learn a lot more, how do you learn more about it? Just messing around with your own stuff? I live in Ohio and there's only like two amp techs in a 200 mile radius so it would be neat if I could bias people's amps and do power tube swaps, things like that on the side, hell even to just do it for friends would be cool

I'm a hobbyist amp builder, started about 10 years ago. I also do mods, repairs, and/or builds for local guys at my discretion.

 

[Chance terrill]

So most of the stuff like the mustard caps have a wire meeting them underneath on Dave's new method? I guess what I'm asking is do all those caps and resistors go to wires or traces on the new board.... Idk what b+ busse or ground plane are

 

[CornNutz]

So most of the stuff like the mustard caps have a wire meeting them underneath on Dave's new method? I guess what I'm asking is do all those caps and resistors go to wires or traces on the new board.... Idk what b+ busse or ground plane are

It's a mix.
Some go to wires i.e. a lone via/eyelet where just the component, and a wire meet then the wire goes to a pot, or tube socket.
But some go to a via/eyelet that connects to a PCB trace.

Hence "Hybrid"

 

[Chance terrill]

Oooooooh OK that makes sense.... Thank u, u have been super helpful and shed light on so many of my foggy areas.... I seriously appreciate u taking the time to explain this stuff to my stupid ass

 

[Chance terrill]

One more question if I may..... Is it normal for amps to sound brighter and brighter as u turn them up? Or is it because ur ears are just more sensitive to the higher frequencies so it seems brighter?

 

[CornNutz]

One more question if I may..... Is it normal for amps to sound brighter and brighter as u turn them up? Or is it because ur ears are just more sensitive to the higher frequencies so it seems brighter?

Yes most get brighter, and can get harsh on your ears as you crank the volume. You typically adjust the presence down, and/or the treble control down as the volume gets louder.

Also very dependent on the room you're in. I usually reach for the Presence first to adjust to the room.

 

[Chance terrill]

It's hard to know what's actually going on when I dime my dirty shirley through my 412.... It starts messing with my ears after like 20 minutes and I don't know what it actually sounds like anymore because my ears can't process it or something...... Probably not good to stand in front of it for hours like I do while playing it dimed...... How loud would u say my dirtyshirley is compared to a 1987? I've heard people say Plexis are way louder than Friedmans but I can't even imagine something more loud lol.....when I dime my shirley it literally starts to hurt after a while

 

[CornNutz]

Back in the plexi days, people dimed them for two reasons.
1). To get it into distortion. Plexi's only had volume knobs, but when dimed they acted like gain knobs. But there was no master volume so you just had to live with the amp at max volume, if you wanted that good distortion.
2). Many venues back in the day did not have a sound system capable of mic'ing everything so the guitars needed to be loud anyway.

Modern amps like your Shirley don't need to be dimed. If you're playing in a band, your master volume on your shirley should probably be around 10-12 o'clock.

Also what you are describing is ear fatigue, you are needlessly punishing your hearing by diming that amp

 

[Chance terrill]

But isn't that the only way to get the power tubes saturating?