Jordan 80

[earache]

Hello

I was wondering if someone has the schematic for a Jordan 80 solid state amplifier and would share.

Thanks in advance!

Earache

[earache]

Bump!

[Jazz P Bass]

Never heard of it.
Bump.

[vintagekiki]

If it is helpful only Jordan 120 140

http://www.schematicsunlimited.com/j/jordan

http://www.schematicsunlimited.com/j/jordan/jordan-120-140-amplifier-schematic

[teemuk]

I've seen schematics for J120/J140 and J110. They are all somewhat different.

In common, they all have discrete preamps and a Baxandall-ish tonestack. J110 has passive stack, 120/140 active. Gain stage designs are different in both, so is overall voicing. 120/140 has a somewhat modern power amp design, Sziklai output (with gain) driven by opamp. There is current feedback. The 110 has entirely discrete power amp and no current feedback. It still definitely has a "late 1960's" power amp design (not earlier), being the typical differential input stage with one input amplified by single-ended common emitter amp, which's collector signal is then buffered by a push-pull emitter follower stage. No "older" -type circuitry with interstage transformers and such.

If you can draw some helpful similarities out of that then I guess it's all nice. Personally I couldn't.

I think the J80 is overall few years newer design than 110, 120 or 140 so might be even less similarities.

My advise is that you probably spend more time hunting the schematic than sketching it out yourself. Overall we are talking about some very simple and basic design so if it has issues you likely don't even need a complete schematic to fix them because you can likely manage by simply tracing a few "clues" of the troubled circuit part.

[vintagekiki]

Jordan Entertainer J110 schematics

http://www.ssguitar.com/index.php?topic=3394.0

http://www.ssguitar.com/index.php?action=dlattach;topic=3394.0;attach=4298;image

http://www.ssguitar.com/index.php?action=dlattach;topic=3394.0;attach=4300;image

[earache]

Thanks everybody - you are a great help. I will
let you know how I do.