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11blueegyptians
New member
16/10/16. Yep, that’s the schematic I have.
Thanks for all the info. I really appreciate it!
Thanks for all the info. I really appreciate it!
fusedbrain
Well-known member
I owned a 2014 Smallbox. The hybrid PCB version but still with Mallory caps.
The first voltage divider was 68k / 100k to ground. First coupling cap was .0047uf.
The entire pre amp was fed from a single 10k + 16uf filter, as stated above.
That amp sounded very good.
I have the same era BE100, so the Smallbox went in a deal for an LP Custom.
I believe that era BE100 is the best sounding / feeling due to the power supply design used ( and since changed with the swap to Synergy caps in the later amps )
The configuration of the power supply rail is the key to getting the desired tones and feel with most amps / mods.
The first voltage divider was 68k / 100k to ground. First coupling cap was .0047uf.
The entire pre amp was fed from a single 10k + 16uf filter, as stated above.
That amp sounded very good.
I have the same era BE100, so the Smallbox went in a deal for an LP Custom.
I believe that era BE100 is the best sounding / feeling due to the power supply design used ( and since changed with the swap to Synergy caps in the later amps )
The configuration of the power supply rail is the key to getting the desired tones and feel with most amps / mods.
CornNutz
Well-known member
fusedbrain":1edqxm14 said:
Alright so both schematics have errors on them.
Yeah that single node 10k+16uf for the whole preamp is from jtm45. The DS has the same, except with a tube rectifier.
I just converted a 50w plexi to that single node 16uf filter, and did the Dirty Shirley circuit in the pre. DAYUM it's soooooo good, guy is coming to pick that amp up tonight, and I told him he's gonna have to fight me for it.
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11blueegyptians
New member
The schematic I have has a 10k between each of the 3 preamp tubes.
Drawing by E.S. I imagine you all have seen it.
Drawing by E.S. I imagine you all have seen it.
fusedbrain
Well-known member
Yes, I believe that's the drawing we are all talking about.11blueegyptians":145aeb50 said:
It's not correct
fusedbrain
Well-known member
Dirty Shirley circuit is some of Dave's best workCNutz":1bojbq7t said:fusedbrain":1bojbq7t said:
Alright so both schematics have errors on them.
Yeah that single node 10k+16uf for the whole preamp is from jtm45. The DS has the same, except with a tube rectifier.
I just converted a 50w plexi to that single node 16uf filter, and did the Dirty Shirley circuit in the pre. DAYUM it's soooooo good, guy is coming to pick that amp up tonight, and I told him he's gonna have to fight me for it.
My DS clone is one of my favorite amps.
I can get better high gain tones with other amps, but the DS set to lower gain is the best JTM45 tone I've ever heard. Just F'n spectacular
I actually ditched the 3.3k/.68uf option on the structure switch, and I just run 10k / 4.7k sellectable via foot switch as a boost function.
Damn I love that amp
J
Jon BCN
Active member
fusedbrain":8g8amgkm said:Dirty Shirley circuit is some of Dave's best work
My DS clone is one of my favorite amps.
I can get better high gain tones with other amps, but the DS set to lower gain is the best JTM45 tone I've ever heard. Just F'n spectacular
I actually ditched the 3.3k/.68uf option on the structure switch, and I just run 10k / 4.7k sellectable via foot switch as a boost function.
Damn I love that amp
The new Twin Sister seems to be better at high gain than the regular DS.
fusedbrain
Well-known member
Judging by that Johan Segeborn Twin Sister vid, yes I would agree.Jon BCN":2mfojl6q said:
The addition of the bright switches helps, as does the speaker choice.
It should also be noted that Dave appears to have moved away from using those small, black silver mica caps for treble peakers and tone stack, in favor of a ceramic style in some newer builds. This may account for some of the aggressiveness in the Twin Sister tone.
Those little black mica caps are smoooooth......and yes, it DOES make a difference
Also, I didn't mean to imply that higher gain tones with regular DS are lacking. They are quite good.
Just that with tube rectifier and lower filtering, it is not my first choice for that sound.
CornNutz
Well-known member
fusedbrain":2ret9r2y said:It should also be noted that Dave appears to have moved away from using those small, black silver mica caps for treble peakers and tone stack, in favor of a ceramic style in some newer builds. This may account for some of the aggressiveness in the Twin Sister tone.
Those little black mica caps are smoooooth......and yes, it DOES make a difference
Dave told me he now uses Vishay 562R10TST47 for 470pf. I ordered some, but have not tried them yet. I've been using Vishay ceramics for awhile, but there are so many different ceramic dielectric types, and yup they all sound different. The one Dave is using has X5F dielectric, I've used those in different values, and they sound good.
fusedbrain
Well-known member
CNutz":3qr1aat0 said:fusedbrain":3qr1aat0 said:It should also be noted that Dave appears to have moved away from using those small, black silver mica caps for treble peakers and tone stack, in favor of a ceramic style in some newer builds. This may account for some of the aggressiveness in the Twin Sister tone.
Those little black mica caps are smoooooth......and yes, it DOES make a difference
Dave told me he now uses Vishay 562R10TST47 for 470pf. I ordered some, but have not tried them yet. I've been using Vishay ceramics for awhile, but there are so many different ceramic dielectric types, and yup they all sound different. The one Dave is using has X5F dielectric, I've used those in different values, and they sound good.
Thanks for that! Those are available in 10% tolerance in all the good values from Mouser.
I think I'll order some up and try 'em.
Funny thing about those black silver mica caps: In all the Friedman style builds I've done, I could never get the amps to sound right, or "like a Friedman" unless I used those mica caps, and that particular ( and now obsolete ) .680uf electrolytic he uses on the cathodes.
Sum of the parts......
CornNutz
Well-known member
fusedbrain":2iawxg3z said:
True. I bought 50 or so of those .68 Nichicon PM series caps when I seen they were obsolete. I should have bought more. Those sound great in a lot of different circuits.
I also started thinking about the longevity of those, I mean they are electrolytic, they will need to be replaced at some point.
J
Jon BCN
Active member
fusedbrain":2ck4xe5p said:Judging by that Johan Segeborn Twin Sister vid, yes I would agree.Jon BCN":2ck4xe5p said:
The addition of the bright switches helps, as does the speaker choice.
It should also be noted that Dave appears to have moved away from using those small, black silver mica caps for treble peakers and tone stack, in favor of a ceramic style in some newer builds. This may account for some of the aggressiveness in the Twin Sister tone.
Those little black mica caps are smoooooth......and yes, it DOES make a difference
Also, I didn't mean to imply that higher gain tones with regular DS are lacking. They are quite good.
Just that with tube rectifier and lower filtering, it is not my first choice for that sound.
The BE100 Deluxe seems to be more aggressive too, it has a grain almost fuzz like in the distortion in the videos I have seen, reminds me a little bit of the Butterslax, but not that extreme grainy like.
Doesn't seem as polish and smooth as previous itinerations.