Wanna build a '67 superbass, where can I find the specs?

[wildebassman]

I have a set of trannies for a 100w build. Where can I find specs for a 1967 10,000 superbass amp? I mean board, filtercaps etc...

Thanks,

Dennis.

[Roe]

there's many variations in 67. a 10000 series could be a jmp like george/plexi replica sells or the earlier dual rectifier amps http://folk.ntnu.no/roef/JTM100.html

take a look in the tech ref section

[wildebassman]

Mange tak Roe. I was thinking about one similar to what George is selling as Metropoulos 10,000 series.

Cheers,

Dennis.

[Roe]

you need to make some important decisions (or experiment a little):
- 16uf or 50uf at the screens?
- 3h or 5h choke?
- 1202-119 or 1202-132ot or even a dagnall c1998 like the last 10000 series had
- nfb is prob 27k at 8ohms or 47k at 8ohms but I'm not sure

[Roe]

layouts http://forum.metroamp.com/viewtopic.php?f=26&t=2875http://forum.metroamp.com/viewtopic.php?f=26&t=2941http://forum.metroamp.com/viewtopic.php?f=26&t=11948

the george specs appears to be 50uf on the screens (try the sozo royal) and a 5h 352-114 choke (although one of the amps pics appears to have had a mm choke - possibly a 3h). also OT is 1202-132. unless I'm mistaken PT is sometimes 1.5" 1203-80, other times "2 1203-80. caps are sozo vintage

I'm not sure what pi filtering would be, but a dual 32uf cap should give two nice options (32uf or 64uf)

[wildebassman]

Thanks again, this will give me some food for thought.....

Cheers,

Dennis.

[Roe]

personally I'd use 50uf on the screens with a marstran 3h choke or 16uf and george's 5h choke. use sozo royal caps (or 2 BC 33uf caps in series in the case of 16uf). For PI I'd use a f&t dual 32uf and for preamp two BC 22uf caps.

I'd gone with martran 1203-80 and 1202-132. and sozo vintage coupling caps or mustards. and larry grounding.

[wildebassman]

Thanks for the input mate... will let you know what I'll do.

Cheers,

Dennis.

[neikeel]

First questio I would ask is what trannies you have?

http://forum.metroamp.com/viewtopic.php?f=22&t=6599

I have a clone with 1202-43 (KT66s) set up as 45/100

http://s76.photobucket.com/albums/j2/ne ... res038.jpg,

an original '67 with 1202-119 using stock filtering, dual rectifiers and EL34s

http://s76.photobucket.com/albums/j2/ne ... Superlead/,

I also have a Black Flag clone I built with 1202-132

http://s76.photobucket.com/albums/j2/ne ... ck%20Flag/.

The boards on these are very similar (the KT66 amp only has 22uF x2 in preamp and 270k mixer resistors) with shared cathode on V1 and 56k/250pF tone stack with 0.1uF PI couplers. The KT66 amp has 27k on 16ohm NFB, the first EL34 27k on 8ohm and the -132 amp 47k on 8ohm.

I used the -132 for the latter as it is still 2" core but is for EL34s and has 4/8 and 16 ohm taps. In this amp I used 50uF mains filtering (x4 47uF in series parallel), 22uF screens (47uF x2 in series) and 22uF PI (47uF x2 in series) and 32uF+32uF in preamp.

The later 10 series filtering is the same as my 68SL

http://s76.photobucket.com/albums/j2/ne ... Superlead/

but the same preamp as the early amps (ie SB) as Roe says filtering on these is 50mains, 16screens, 48PI (at least mine is ) and 32/32 preamp.

Long and short is, I have done my research!

I would build a -132 OT with EL34s and 50uF mains, 22uF screens, 22uF PI and a -114 choke, stock 1203-80PT and 47k on the 8ohm tap NFB.

Keep us posted

[wildebassman]

First questio I would ask is what trannies you have?

http://forum.metroamp.com/viewtopic.php?f=22&t=6599

I have a clone with 1202-43 (KT66s) set up as 45/100

http://s76.photobucket.com/albums/j2/ne ... res038.jpg,

an original '67 with 1202-119 using stock filtering, dual rectifiers and EL34s

http://s76.photobucket.com/albums/j2/ne ... Superlead/,

I also have a Black Flag clone I built with 1202-132

http://s76.photobucket.com/albums/j2/ne ... ck%20Flag/.

The boards on these are very similar (the KT66 amp only has 22uF x2 in preamp and 270k mixer resistors) with shared cathode on V1 and 56k/250pF tone stack with 0.1uF PI couplers. The KT66 amp has 27k on 16ohm NFB, the first EL34 27k on 8ohm and the -132 amp 47k on 8ohm.

I used the -132 for the latter as it is still 2" core but is for EL34s and has 4/8 and 16 ohm taps. In this amp I used 50uF mains filtering (x4 47uF in series parallel), 22uF screens (47uF x2 in series) and 22uF PI (47uF x2 in series) and 32uF+32uF in preamp.

The later 10 series filtering is the same as my 68SL

http://s76.photobucket.com/albums/j2/ne ... Superlead/

but the same preamp as the early amps (ie SB) as Roe says filtering on these is 50mains, 16screens, 48PI (at least mine is ) and 32/32 preamp.

Long and short is, I have done my research!

I would build a -132 OT with EL34s and 50uF mains, 22uF screens, 22uF PI and a -114 choke, stock 1203-80PT and 47k on the 8ohm tap NFB.

Keep us posted

Well..... I have magnetic components trannies and choke laying around....

Cheers,

dennis.

[neikeel]

Well..... I have magnetic components trannies and choke laying around....

Cheers,

dennis.

Which ones?

[wildebassman]

Neil,

I have: 40-18026 OT,40-18024 PT, and 40-18032 5H choke.

Cheers,

Dennis.

[neikeel]

Neil,
I have: 40-18026 OT,40-18024 PT, and 40-18032 5H choke.
Cheers,
Dennis.

What are they equivalent to?
1.5" or 2" core OT, 4k or 1k7 primary impedence
What is rectified B+ of the PT likely to be?
Those may influence the type of amp build a little.
Neil

[wildebassman]

Neil, sorry for the late reply, been working a lot lately and been out of the country. The PT is 350V, 175-0-175 Volts. Not sure about the core of the OT, I know it's modelled after a JCM800 OT. Which build do you recommend on these specs?

[Roe]

that OT is prob better for a superlead or 2203. I prefer a drake for a 67