Ry Cooder's Borderline Special

[10thTx]

Have a HARD time blvg it wouldn`t make a difference, you think he screwed up on purpose?

You may be totally right that it makes a difference. And no I don't think he screwed up.

What I am saying is (with the severe limits of knowledge that I have) that I don't understand what difference it would make?

What difference does it make whether you have a resistor then cap to ground ............VS. a cap then resistor to ground? I'm viewing the presence pot as "the" resistor.

It's simply more of a statement of my lack of knowledge. I am not saying your wrong. I'd be willing to have you or someone else educate me on why it matters.

With respect, 10thtx

[vibratoking]

The order of the cap and resistor does not make any difference.

[JazzGuitarGimp]

The order of the cap and resistor does not make any difference.

+1

[bluesfendermanblues]

LFBN on V1b should be not be in a classic circuit - it is belongs to the skyliner

AFAIU this layout http://ampgarage.com/forum/download/file.php?id=14346 it shows the circuit of a typical "low plate classic" ODS and shows a LNFB loop at V1b. So why do you think that such a LNFB loop "should not be in a classic circuit" - as you wrote? Or did I misunderstand what you wrote?

Cheers,

Max

According to the layout of (#124 prior to Skyliner mod) you are probably right. Got it confused with the 2nd and 3rd layout.

[groovtubin]

Have a HARD time blvg it wouldn`t make a difference, you think he screwed up on purpose?

You may be totally right that it makes a difference. And no I don't think he screwed up.

What I am saying is (with the severe limits of knowledge that I have) that I don't understand what difference it would make?

What difference does it make whether you have a resistor then cap to ground ............VS. a cap then resistor to ground? I'm viewing the presence pot as "the" resistor.

It's simply more of a statement of my lack of knowledge. I am not saying your wrong. I'd be willing to have you or someone else educate me on why it matters.

With respect, 10thtx

All i`m trying to do is get the circuit drawed as per pic! lol! ( and a big thank you!) It IS a different set-up, In a HRM circuit, the pres cap isn`t tied to the TOP of the tail resistor..nor 183...nor any of the massive layouts i`ve seen here...His amp IS very bright to my ears, i`m just trying to understand it myself, to draw it inconsistent with the pic so graciously given to us by Gil A. is unthinkable.. lol!!

peace, jp

[Max]

The layout for the low plate classic was taken from the layout of 124 which was origionally a low plate classic before the upgrade to Skyline EQ..

At the time this was all we knew about the low plate classic amp?

After the Boarderline pics were graciously given to us by Gil clearly shows this amp to be a LOW PLATE CLASSIC! w/trem added It would also make some sense that he used 4.7 uf on the cathodes since this was a 50w amp!!..

I also went back and checked a few other shots I had of the Carlos Rios (Now owned by Ben Harper) which is also a Low plate Classic 100w and this amp too has 4.7uf on V1 a&b cathodes

Conclusion..Since 124 was updated to Skyliner specs perhaps the bypass caps were also changed to suit some customers needs (using 10uf)instead of the normal 4.7uf CL1 If this is the case we should rethink the layout for the low plate classic
I cannot tell from the shots Gil provided that 124 had these 10uf caps and I assume IC-racer who origionally did the boards for the layout I used on 124 and the low plate classic got the info from the hand drawn pics from Billy provided with the pics Gil posted from 124..

AFAIU the schematics of at least two other "classic" ODS amps posted here (#0094 and #0123) http://ampgarage.com/forum/viewtopic.ph ... highlight= they show 5.0uF capacitors where the 124 low plate classic layout in the files section shows these two 10uF electrolytic capacitors. And AFAIU the 124 low plate classic layout in the files section it’s based on two assumptions:

- the value of the two black "TEAPO" capacitors visible on the pictures of #0124 is 10uF.
- the two black "TEAPO" capacitors visible on the pictures of #0124 aren’t part of the skyline update of #0124.

I don’t know if the first assumption is correct, because I’m not familiar with #0124 and I’m not able to read the value of these two capacitors on the pictures of #0124.

I don’t know either if these "TEAPO" capacitors were installed when #0124 was updated to skyline specs, because on the pictures of #0124 I can’t see clearly enough if there’s only blue goop on these two "TEAPO" capacitors or if there are still some small (or even very small) traces of the original black goop on these "TEAPO" capacitors. And at what time these "TEAPO" capacitors first appeared on the market I don’t know either.

The values of these capacitors visible on the low resolution pictures of ODS #0093 (Carlos Rios) posted here http://ampgarage.com/forum/viewtopic.ph ... 297#127297 I can't read either.

Cheers,

Max

[10thTx]

It looks to me like there are 4.7uf cathode caps for V1 and V2 based on this photo:

http://s55.photobucket.com/user/amp_guy ... 5555445562

Also, I am looking at what I think are the vibrato caps and I'm thinking they are .047, .02 & .047? Ampeg used .05 vibrato caps so I know that done at times. Comments?

http://s55.photobucket.com/user/amp_guy ... 3363440941


With respect, 10thtx

[Max]

It looks to me like there are 4.7uf cathode caps for V1 and V2 based on this photo:

http://s55.photobucket.com/user/amp_guy ... 5555445562

Obviously.

Cheers,

Max

[Max]

In this thread you'll find a higher resolution picture of these capacitors in #0093. And Brandon posted in this thread that #0093 is a "low plate classic" ODS 100W with a mid boost: http://ampgarage.com/forum/viewtopic.php?p=81451#81451

Cheers,

Max

[talbany]

I also went back and checked a few other shots I had of the Carlos Rios (Now owned by Ben Harper) which is also a Low plate Classic 100w and this amp too has 4.7uf on V1 a&b cathodes

I thought I said that here!

Those RP/RK parts look stock to me..What do you think Max should we go ahead and change the layout?

Tony

[Max]

should we go ahead and change the layout

.

Tony, IMO it depends:

1st question: What's the correct value of the two TEAPO capacitors visible on the pictures of #0124 posted by Gil Ayan? As I posted in one of my previous posts in this thread I don't know the value of these two TEAPO capacitors in #0124 because the value of these capacitors isn't visible on the pictures posted by Gil Ayan - at least not for me.

2nd question: Are these two TEAPO capacitors a part of the skyline update of #0124 or not? AFAIK no one here knows if these two TEAPO capacitors were fitted when #0124 was updated to skyline specs or when it was originally built with a "classic" tone stack. IMO the only "proof" would be some residual traces of the original black goop on the two TEAPO capacitors or some pictures taken before the update etc.

So IMO - if no one here knows the answers - some kind of written comment in the "124 Low Plate Classic" layout could perhaps explain that the value "10uF" is only based on the handdrawn schematic and isn't based on the pictures.

And in addition a second comment could perhaps explain that it's only an assumption that these two TEAPO capacitors are a part of the "classic" version of #0124 and not a part of the "skyline" update.

And a third comment could perhaps explain that if these two TEAPO capacitors aren't a part of the skyline update but are a part of the original "classic" version, #0124 would be the only "classic" ODS with a value of 10uF known to the members here and that in all the other ODS amps with a "classic" tone stack and a "standard" OD-circuit known to the members here these two capacitors have different values. AFAIR 4.7uF (low plate classic) and 5uF (high plate classic) are the values known to the members here. Or do I remember wrong?

What do you all think about this?

Cheers,

Max

[jelle]

Max, I agree 100%. Doing otherwise would be sloppy in my eyes. What you present is factual. Thanks for that.

[talbany]

1st question: What's the correct value of the two TEAPO capacitors visible on the pictures of #0124 posted by Gil Ayan? As I posted in one of my previous posts in this thread I don't know the value of these two TEAPO capacitors in #0124 because the value of these capacitors isn't visible on the pictures posted by Gil Ayan - at least not for me.

Hand drawn layout Made by(I assume) Billy

Max, I agree 100%. Doing otherwise would be sloppy in my eyes. What you present is factual. Thanks for that.

FACT!!...0124 was updated to Skyline specs...The Carlos Rios amp was not.. ..Wouldn't it make more sense to use an amp that wasn't updated as the reference?

Tony

[Bombacaototal]

Here is the face.

G.

Fascinating info here! Thanks for sharing. Are there any photos of #224? It would be great to see how the front looks at least.

i just found this gutshot from #224, Just wondering if there are any further info

[Bombacaototal]

Was surfin the net and finally found a pic of the back of Ry Cooder's Borderline Special. Never seen a pic of the rear of the chassis so maybe it can shine some light on it. It's clearly a very unique amp.

Very cool amp BTW.

Here's a link of what the amp sounded like BTW (can be see behind him):

http://www.youtube.com/watch?v=9OIgZQj1 ... re=related

http://www.youtube.com/watch?v=6efQ_GyQW3o

This link has some additional info on this amp

http://ampgarage.com/forum/viewtopic.ph ... 9&start=60