[johnjen]

Red is 'usually' denoted as 'right'.
But if this the darkvoice amp you should be able to use a dvm and verify the connection from the red marked signal lead to the right channel input rca jack.

JJ

 

[therremans]

Red is 'usually' denoted as 'right'.
But if this the darkvoice amp you should be able to use a dvm and verify the connection from the red marked signal lead to the right channel input rca jack.

JJ

Good point
Edit: the signal was broke when I removed the pot. I can keep looking at some photos or post on the DV thread

 

[Tjj226 Angel]

Good point
Edit: the signal was broke when I removed the pot. I can keep looking at some photos or post on the DV thread

Red should be right channel. Red almost always denotes the right channel.

 

[therremans]

yes and I see another pcb where left is yellow.

 

[johnjen]

MAJOR EXPERIMENT UNDER WAY!!!!!
Details to follow!
And just when the amp started to really SING!!!!
PART II…



So after another round of circuit surgery and adding even more caps (see photo) the hum is gone, the dynamics have returned, and the amp is returning to it's previous 'glory'.
The Ultrapath has now been refined and matched more closely to the gain of the output tubes and the cathode bias bypass caps have been re-installed.

And so this configuration has very few hrs of operation thus far so a more definite eval will have to wait, but…
It was immediately apparent the SQ had returned and began noticeably blossoming even before the first hr. of operation.
There is still a bit of tweaking to do as I need to find a 33µf 600vdc rated cap to replace the stack of caps and perhaps a bit more power supply refinements.

And today even this early in the settling in process, the SQ has taken a BIG step up to it's previous peak and it will continue to become yet more refined for the rest of the day.

Just like I like…

JJ

 

[bcowen]

MAJOR EXPERIMENT UNDER WAY!!!!!
Details to follow!
And just when the amp started to really SING!!!!
PART II…



So after another round of circuit surgery and adding even more caps (see photo) the hum is gone, the dynamics have returned, and the amp is returning to it's previous 'glory'.
The Ultrapath has now been refined and matched more closely to the gain of the output tubes and the cathode bias bypass caps have been re-installed.

And so this configuration has very few hrs of operation thus far so a more definite eval will have to wait, but…
It was immediately apparent the SQ had returned and began noticeably blossoming even before the first hr. of operation.
There is still a bit of tweaking to do as I need to find a 33µf 600vdc rated cap to replace the stack of caps and perhaps a bit more power supply refinements.

And today even this early in the settling in process, the SQ has taken a BIG step up to it's previous peak and it will continue to become yet more refined for the rest of the day.

Just like I like…

JJ

Where be the photo? I'm so dejected. Or is this a "Film at 11" type thing?

 

[johnjen]

Where be the photo? I'm so dejected. Or is this a "Film at 11" type thing?

Ok so JUST for you, you know, so's you can feel 'special,' and not left behind, and alone, and like you have no friends…
hahahahahahahahahah



JJ
Oh and it's already been modified one step beyond this but that will be the next post.

 

[bcowen]

Ok so JUST for you, you know, so's you can feel 'special,' and not left behind, and alone, and like you have no friends…
hahahahahahahahahah



JJ
Oh and it's already been modified one step beyond this but that will be the next post.

Balance has been restored to my universe. Thanks!!

 

[johnjen]

Balance has been restored to my universe. Thanks!!

I'm a giver not a taker!!!! hahahahahahahahahahah

But soon enough I'm gunna hafta post more about this latest set of cooking experiments from "JJ's desktop electronic surgical la-BOR-atory and solder slinging workstation'.

And we (meaning mostly him) cooked up yet another couple of tweaks on top of tweaks based upon previous tweaks ad absurdum…
And I'm think'n, in full on uhmerikun, if a little is good too much should be about right, right?

So another round of experiments may be looming in the 'above and beyond' category of circuit dynamics as in, 'lets try THIS and see what happens'…

But right now, as I type this (after ≈1hr of playing time) the SQ has reached new high water peaks, always a good sign.
So I figure why stop now if we're on a roll, right???
hahahahahahahahahaha (this is usually where disaster raises it's scatter brained head and goes, Huh?)

But I always fall back on the sage words of my main man Harry, (Dirty Harry) "A Man's gotta know his limitations".
hahahahahahahahahahaha

A sneak peek of the latest set of Ultrapath 'enhancement' tweaks, in this direct coupled prototype/test bench/research mule-tool HP amp.

The left channel showing the B+ across the 71A output tube


The right channel showing the B+ across the other 71A output tube


And the SQ is blossoming yet again and I'm desperately trying to NOT make any more changes, at LEAST for a couple of days and all the while the itch to sling hot solder knows no bounds.
hahahahahahahahahaha

JJ

 

[bcowen]

So another round of experiments may be looming in the 'above and beyond' category of circuit dynamics as in, 'lets try THIS and see what happens'…

When *I* do that, smoke usually happens.

The left channel showing the B+ across the 71A output tube...

The right channel showing the B+ across the other 71A output tube

A 0.03v variance? Probably your meter. Have you had it calibrated recently?

 

[johnjen]

When *I* do that, smoke usually happens.

Here in the lab we take ALLLLLL necessary precautions.
There is a fire extinguisher near by (I can't remember if I got it re-filled or not from last time, hmmmm )
And as you can see I have the finest (chinesium) LONG reach probes that can all to easily span the gap between tube socket pins, so at least I don't get electromotated across the room after the blinding flash…
And there is a fire proof hoody overcoat somewhere around here, buried under who knows what, ya know just in case the obviously defective parts "can't handle the truth" er sumpt'n…

And of course there is the de rigueur smoke replacement and restoration kit, (with a lifetime supply of refill cartridges, (just add water)) readily at hand for those 'quick fixes'.

And the motto hanging on the wall that says "You Can NEVER Be To Careful", which is covered by postit notes and phone numbers for Dog only knows who anymore.
Just as a reminder of how I managed to live to tell about those 'memorable' past exploits…
hahahahahahahahahahahahahaha

A 0.03v variance? Probably your meter. Have you had it calibrated recently?

Calibrate my meters, really?
You want me to live on the edge of trying to not only be precise but accurate as well????

Is this called pushing my buttons AND yanking my chain and at the SAME time?

I tell ya, some peoples kids…
hahahahahahahahahahahahahahaha

JJ

 

[therremans]

I came here to ask this question.. is traditional pull back cloth wire (22awg, waxed insulation) okay for building amps? I was in the process of replacing some wire in mine and wanted to be sure this wouldn’t cause interference/humming problems.

I now see the amp above @johnjen posted may be actually using it.

Thanks

 

[Tjj226 Angel]

I came here to ask this question.. is traditional pull back cloth wire (22awg, waxed insulation) okay for building amps? I was in the process of replacing some wire in mine and wanted to be sure this wouldn’t cause interference/humming problems.

I now see the amp above @johnjen posted may be actually using it.

Thanks

Yeup, wax wire is fine. Just be careful though, I used to use vintage WE wire in my amps, and the wire kept stress fracturing and breaking off. Make sure you use decent wire so that you don't have those problems.

 

[bcowen]

Here in the lab we take ALLLLLL necessary precautions.
There is a fire extinguisher near by (I can't remember if I got it re-filled or not from last time, hmmmm )
And as you can see I have the finest (chinesium) LONG reach probes that can all to easily span the gap between tube socket pins, so at least I don't get electromotated across the room after the blinding flash…
And there is a fire proof hoody overcoat somewhere around here, buried under who knows what, ya know just in case the obviously defective parts "can't handle the truth" er sumpt'n…

And of course there is the de rigueur smoke replacement and restoration kit, (with a lifetime supply of refill cartridges, (just add water)) readily at hand for those 'quick fixes'.

And the motto hanging on the wall that says "You Can NEVER Be To Careful", which is covered by postit notes and phone numbers for Dog only knows who anymore.
Just as a reminder of how I managed to live to tell about those 'memorable' past exploits…
hahahahahahahahahahahahahaha


Calibrate my meters, really?
You want me to live on the edge of trying to not only be precise but accurate as well????

Is this called pushing my buttons AND yanking my chain and at the SAME time?

I tell ya, some peoples kids…
hahahahahahahahahahahahahahaha

JJ

LOL! Yeah, it's always those other people's kids. Or their parents.

I prefer my sign that says "Take Your Farad Like A Man."

 

[johnjen]

I came here to ask this question.. is traditional pull back cloth wire (22awg, waxed insulation) okay for building amps? I was in the process of replacing some wire in mine and wanted to be sure this wouldn’t cause interference/humming problems.

I now see the amp above @johnjen posted may be actually using it.

Thanks

As an added note.
The woven cloth (waxed or oiled or not) isn't the best insulation available at least in terns of preventing shorts or grounding out to the top plate or other surfaces and other wires.
It does (or can) sound better due to the dialectric having less 'memory' like plastics do.

So if you do use it make sure it isn't hard pressed up against any other metal surfaces, especially going around corners or at 90º crossings with other wires etc.
It can be all to easy to penetrate the insulation layer and short out.

Like when you cinch up that ty-rap nice and tight squeezing a bundle of wires together…
Which is why you don't see ANY ty-raps in the Purp-Amp and all of the wires hugging the top plate are actually lifted off, if ever so slightly…
EDIT: Other than for securing objects (caps etc) in place.

Just a word of caution.

JJ