What Do You Guys Think Of This?

mlucitt

mlucitt

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I have been trying to find decent RCA Phono Jacks to fit in the 1/2" holes of our PL and WOA chassis. Most of the 'good' RCA jacks (Cardas, Kimber, Neutrik) are 3/8" hole size. There are "audiophile" 1/2" jacks that cost $98.00-$125.00 each and there are Chineeeese imitation jacks that cost $2.00-$20.00 each. I try to avoid anything Chineeeese in these wonderful amps.
Anyway, I stumbled across these last night. They are manufactured in a small Pro-audio (recording equipment) shop in Chino, CA called Manley. Run by EveAnna Manley, she is the daughter of Albert J. Dauray, the owner of Ampeg (sadly sold to Magnavox in 1972), and she is a pistol. The website www.manley.com has some nice images and videos, and their equipment line looks good.
https://www.ebay.com/itm/142339553194

I bought some of the RCA jacks to check them out, and from first Ebay glance they seem to fit the Bob Carver paradigm - rugged, attractive, purposeful. And the price is good for a Made in the USA product.
Thoughts?
 
WOPL Sniffer

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On the inside, I use one of the original fiber stepped washers, and on the outside, the red and the white nylon stepped washers. I solder a ground wire between them.
 
mlucitt

mlucitt

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WOPL Sniffer said:
On the inside, I use one of the original fiber stepped washers, and on the outside, the red and the white nylon stepped washers. I solder a ground wire between them.
Click to expand...
I like the Cardas, they are a little pricey, but not anywhere near the other 'audiophile' RCA jacks. I want to see how these Manley jacks compare to the well-regarded Cardas jacks.
Do you solder the ground wire around the base of the shells?

Also, not being critical here and I may be wrong but, by connecting the grounds of the inputs together, are you defeating the true 'Dual Mono' architecture of the control board?
 
WOPL Sniffer

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mlucitt said:
I like the Cardas, they are a little pricey, but not anywhere near the other 'audiophile' RCA jacks. I want to see how these Manley jacks compare to the well-regarded Cardas jacks.
Do you solder the ground wire around the base of the shells?

Also, not being critical here and I may be wrong but, by connecting the grounds of the inputs together, are you defeating the true 'Dual Mono' architecture of the control board?
Click to expand...

The grounds will meet on the Control Board anyway. And, as far as expensive, a WOPL cost serious cash to build and I don't scrimp on parts.
 
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WOPL Sniffer

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Check this out.... With No inputs or grounds (the shielded Cables from input to volume pot to the control board) connected to the Control board, and you ohm the left and right ground where the shield goes, the Ohm meter says "ZERO" ohms......
 
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Don't let "Dual Mono" get you tripped up. Sooner or later, upstream, all points meet whether it be the main Power, or or or....... It can't be helped.
 
mlucitt

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I am building two PL700B's right now. Two more PL700 II's just arrived in the boxes.
The way I understand the Right Channel and Left Channel Connection Lists in the Rev C Backplane Assembly Notes... the Left and Right signal grounds share the same point at the Star ground unless you connect them together someplace else. If you hold the Rev G1 board up to the light, you can see through it and the Right and the Left channels are completely isolated from each other, they don't share a ground on the Control Board. The Pin 5L and the Pin 5R signal grounds go to the respective Backplane Boards and each Backplane Board is separately grounded at the Star Ground (Bulk Capacitor Buss Bar).

I know about this stuff, I worked on steel ships floating in salt water, you worked on aircraft, where there is no ground (ducking now).
 
WOPL Sniffer

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mlucitt said:
I like the Cardas, they are a little pricey, but not anywhere near the other 'audiophile' RCA jacks. I want to see how these Manley jacks compare to the well-regarded Cardas jacks.
Do you solder the ground wire around the base of the shells?

Also, not being critical here and I may be wrong but, by connecting the grounds of the inputs together, are you defeating the true 'Dual Mono' architecture of the control board?
Click to expand...

Mark, the analog grounds for the shield of the input cables, go from pin 2 L/R and through to pin 5 L/R where the all get tied to ground. It's all the same point. Grounding the opposite end has no affect since it's already grounded but I don't like one end of the shield floating. Joe may be able to shed some light on it if it is vexing you.
 
mlucitt

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WOPL Sniffer said:
Mark, the analog grounds for the shield of the input cables, go from pin 2 L/R and through to pin 5 L/R where the all get tied to ground. It's all the same point. Grounding the opposite end has no affect since it's already grounded but I don't like one end of the shield floating. Joe may be able to shed some light on it if it is vexing you.
Click to expand...
I agree to a point. Pin 2L is connected to Pin 5L and Pin 2R is connected to Pin 5R. There are no connections from L to R. So the voltage amplification on the Control Board and the current amplification on the Backplane Boards occur ahead of the common point ground which is the Star ground. You can connect the input grounds to each other in your amplifiers if you want, of course.
 
WOPL Sniffer

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mlucitt said:
I agree to a point. Pin 2L is connected to Pin 5L and Pin 2R is connected to Pin 5R. There are no connections from L to R. So the voltage amplification on the Control Board and the current amplification on the Backplane Boards occur ahead of the common point ground which is the Star ground. You can connect the input grounds to each other in your amplifiers if you want, of course.
Click to expand...

Pin 5 is analog ground thats where they both go to (down to the back plane). THEY ARE COMMON and connected. I have an open amp and will show you with nothing hooked up to the inputs on pin 2. Ask Joe. Both L/R share ground. There is NO WAY around it.
 
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WOPL Sniffer said:
Pin 5 is analog ground thats where they both go to (down to the back plane). THEY ARE COMMON and connected. I have an open amp and will show you with nothing hooked up to the inputs on pin 2. Ask Joe. Both L/R share ground. There is NO WAY around it.
Click to expand...
True that Perry. Ideally each channel should only join at that single point ground at one point when you use the Dual Mono board assembly. Keep everything totally separate until it reaches that one inevitable shared point (bus bar between the bulk caps) to achieve the highest possible channel separation. With a single shared transformer and bulk power supply, that is the best you will be able to achieve.
 
mlucitt

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Thanks for the pictures, Sniff. It clears things up a bit. Joe, I read a section in Randy Sloan's book, "High Power Amplifier Construction Manual" in chapter 12 on page 382. He states, "You do not want the Star ground point (he calls it the High Quality Ground, HQG) to literally be the common connection point of the reservoir capacitors because of the high charge-current turbulence at this point." He goes on to state, " The connection wire running from the reservoir capacitors to the HQG point should be a very heavy gauge."
I realize Phase Linear soldered every ground to the Bulk Capacitor common point, was that a cost-saving measure? Should we build these amplifiers the way Sniff does, with one wire from the Bulk Capacitor common point to the Star chassis/ground, where all the grounds should go?
 
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Randy Sloan is describing a different setup in his article evidently.

Phase Linear did it pretty textbook and well in their establishment of the single point ground as that copper bus between the caps. It does not get much better than that....the single point ground in a PL amp should be this bus bar connection. Thicker is better as always for that bus bar but they did it right.
 
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