NOS parts in 183

[qtone]

183/102 update !
Greg installed basically the same parts into my amp and it improved the sound
5000% in my mind.

Today we seek other old parts locally at a place I took Greg too.
Those parts will as well go into the amps..

I cant see how it can get any better but im all ears..
Waiting on more cable and ends to finish the rack.

The thought of running these amps stereo is driving me to drink again.
all good things come to those who pay and wait though.

Soon my precious soon.

[bluesfendermanblues]

www.markoparts.com has vintage mepco/electra resistors in suitable values for plates and cathodes.

Thanks, great link.

[Colossal]

The thought of running these amps stereo is driving me to drink again. all good things come to those who pay and wait though.

Soon my precious soon.

Oh, but dear god, that would sound so good in stereo.

[gary sanders]

So far, wow, the parts do certainly make a noticable difference.

Told Ya!!..

Tony

second that!

[brentm]

There must be a scientific reason behind the NOS parts mojo.

Aside from the precision resistors, I wonder about tolerances. Did anyone check the tolerances on their NOS sprague orange drop caps? Some are right on the money, but some are way out there. I bought about 50 .075mf 6PS-S75 caps, and I tested a handful... and as I suspected, some were nearly .1, some were within their acceptable +/- 10 percent. All seemed to be on the heavy side, at least the ones I tested.

Anyway, I'm curious if you guys are measuring the actual values of the components prior to installation?

[ToneMerc]

There must be a scientific reason behind the NOS parts mojo.

Aside from the precision resistors, I wonder about tolerances. Did anyone check the tolerances on their NOS sprague orange drop caps? Some are right on the money, but some are way out there. I bought about 50 .075mf 6PS-S75 caps, and I tested a handful... and as I suspected, some were nearly .1, some were within their acceptable +/- 10 percent. All seemed to be on the heavy side, at least the ones I tested.

Anyway, I'm curious if you guys are measuring the actual values of the components prior to installation?

I don't think there's much science behind it at all, it's simple actually. The current parts aren't made out of the same materials as the older parts. Get away from just values/tolerences and think of parts as different flavors, with different tonal signatures.

My builds generally have been full of these NOS parts. However, I generally treat all builds the same and I try to keep +/- .5>2% ...period. I buy enough of a range of values/material types and cull the closest to my target. For example, if I was actually looking for .075 6PS, I would be buying a range of .056>.082.

If I'm going through the trouble of trying to "clone" something, I'm personally going to chase down period correct parts or the material/electrical equivalents that I seen used in the circuit.

Your mileage, ears or tone may vary.

TM

[talbany]

There must be a scientific reason behind the NOS parts mojo.

Aside from the precision resistors, I wonder about tolerances. Did anyone check the tolerances on their NOS sprague orange drop caps? Some are right on the money, but some are way out there. I bought about 50 .075mf 6PS-S75 caps, and I tested a handful... and as I suspected, some were nearly .1, some were within their acceptable +/- 10 percent. All seemed to be on the heavy side, at least the ones I tested.

Anyway, I'm curious if you guys are measuring the actual values of the components prior to installation?

I don't think there's much science behind it at all, it's simple actually. The current parts aren't made out of the same materials as the older parts. Get away from just values/tolerences and think of parts as different flavors, with different tonal signatures.

My builds generally have been full of these NOS parts. However, I generally treat all builds the same and I try to keep +/- .5>2% ...period. I buy enough of a range of values/material types and cull the closest to my target. For example, if I was actually looking for .075 6PS, I would be buying a range of .056>.082.

If I'm going through the trouble of trying to "clone" something, I'm personally going to chase down period correct parts or the material/electrical equivalents that I seen used in the circuit.

Your mileage, ears or tone may vary.

TM

Now were getting into the art form!!
I agree with Mike The materials used, construction methods and tolerances all play a role.. Resistors in the signal path have a larger impact..Resistors used to say set a ground reference not so much.. (Why you see he used CC in these spots).. Pots the same way..direct signal path like Vol, level, drive and treble so you have to look at trace element compounds and taper..To be able to recognize how different caps, resistors, pots,coax,tubes,layout,lead dress, how all this effects sound is a whole other level of building and design
Ken Fisher once stated resistor direction can also effect tone.. Let's NOT discuss this!!!!!

Tony

[Teleguy61]

Now were getting into the art form!!

Bingo!

[ToneMerc]

There must be a scientific reason behind the NOS parts mojo.

Aside from the precision resistors, I wonder about tolerances. Did anyone check the tolerances on their NOS sprague orange drop caps? Some are right on the money, but some are way out there. I bought about 50 .075mf 6PS-S75 caps, and I tested a handful... and as I suspected, some were nearly .1, some were within their acceptable +/- 10 percent. All seemed to be on the heavy side, at least the ones I tested.

Anyway, I'm curious if you guys are measuring the actual values of the components prior to installation?

I don't think there's much science behind it at all, it's simple actually. The current parts aren't made out of the same materials as the older parts. Get away from just values/tolerences and think of parts as different flavors, with different tonal signatures.

My builds generally have been full of these NOS parts. However, I generally treat all builds the same and I try to keep +/- .5>2% ...period. I buy enough of a range of values/material types and cull the closest to my target. For example, if I was actually looking for .075 6PS, I would be buying a range of .056>.082.

If I'm going through the trouble of trying to "clone" something, I'm personally going to chase down period correct parts or the material/electrical equivalents that I seen used in the circuit.

Your mileage, ears or tone may vary.

TM

Now were getting into the art form!!
I agree with Mike The materials used, construction methods and tolerances all play a role.. Resistors in the signal path have a larger impact..Resistors used to say set a ground reference not so much.. (Why you see he used CC in these spots).. Pots the same way..direct signal path like Vol, level, drive and treble so you have to look at trace element compounds and taper..To be able to recognize how different caps, resistors, pots,coax,layout,lead dress, how all this effects sound is a whole other level of building and design

Tony

Thanks T

Weeks back Taylor mentioned that he didn't have enough NOS for an entire amp. I told him let's install the parts you have in strategic locations.

Exactly Tony, study enough actual Dumbles pictures and there's an established build pattern. It took me a couple of builds using the exact same chassis and contruction techniques to get some baselines on how this stuff all comes together.

So true, that's the difference between an assembler and builder.

TM

[amplifiednation]

So true, that's the difference between an assembler and builder.

TM

Pure gold. This comment changed the way I looked at these amp builds. You guys have been so much help in turning these into an art form.

Tony told me last summer that you need to build about a dozen of these before really figuring out how they work. I don't doubt that at all... But when we have the sharing and collaboration that this forum brings, we can all learn so much quicker. I can not even explain the amount of knowledge I have picked up through my Dumble builds!!!

After swapping out parts in my 102 to NOS CF and MF, the amp was quieter, weeter, smoother, and just overall more pleasing to the ear. It seems like the Marshall guys are doing this too... I'm not sure what other builders.

I can not thank all of you enough. Now go watch my tolex video so i can pay it backwards!! hhaah j/k

[talbany]

Tony told me last summer that you need to build about a dozen of these before really figuring out how they work

Taylor
As good as your amps look and sound!!..For you I need to revise that number down.. Great Job..
This is a wonderful place and can't say how much it has helped me as well!!
We should all try to give back as much as we can and keep the spirit here alive..
Fart on the trolls!!

Exactly Tony, study enough actual Dumbles pictures and there's an established build pattern. It took me a couple of builds using the exact same chassis and contruction techniques to get some baselines on how this stuff all comes together.

Yep!!..All the great ones have a definite pattern ..Old Marshalls, Old Fenders, Vox, Soldano,Wrecks, You can study all these and start to form a pattern in sound!!..(been studying old JTM's lately)..Total amp geek stuff..Ha Ha!!

Tony

[amplifiednation]

Tony told me last summer that you need to build about a dozen of these before really figuring out how they work

Taylor
As good as your amps look and sound!!..For you I need to revise that number down.. Great Job..
This is a wonderful place and can't say how much it has helped me as well!!
We should all try to give back as much as we can and keep the spirit here alive..
Fart on the trolls!!

Exactly Tony, study enough actual Dumbles pictures and there's an established build pattern. It took me a couple of builds using the exact same chassis and contruction techniques to get some baselines on how this stuff all comes together.

Yep!!..All the great ones have a definite pattern ..Old Marshalls, Old Fenders, Vox, Soldano,Wrecks, You can study all these and start to form a pattern in sound!!..(been studying old JTM's lately)..Total amp geek stuff..Ha Ha!!

Tony

Thanks Tony! I've been looking at some Marshall stuff too...we gotta find some amps that don't have Pihers!!! Haha...oh man they are sweet though.

[10thTx]

Any before (NOS) and after (NOS) videos or soundclips available that clearly demonstrate the difference in tone ?

Something like an A/B soundclips comparison?

With respect, 10thtx

[boldaslove6789]

I'll have some clips up soon of my amp after the parts change out, still waiting for some stuff.

[martin manning]

I'm with 10thTx. I don't think I can buy into this unless I can hear the difference in a tightly controlled test, like say switching out the plate loads (new to NOS and back) on V1 with an A-B switch...