Design questions

Paul Joppa · 39828

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Offline Bryon

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Reply #15 on: February 25, 2010, 01:19:01 PM

Earlier in this thread I mentioned a project I am working on, which is a fully shunt-regulated 45 amp - this will be at a level above the Eros and Paramount, and I don't know if there will be enough demand for it to become an actual product.

I'll buy one! [or should I say two as they will be monoblocks]

Bryon



Offline Paul Joppa

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Reply #16 on: February 25, 2010, 07:28:19 PM
No, actually I am looking at the Paramount chassis and the PT-3 (SEX and Foreplay) power transformer. There are several variants on my drawing board, so no point in getting specific - it will undoubtedly change!

Paul Joppa


Offline Jim R.

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Reply #17 on: February 27, 2010, 03:26:44 PM
Paul,

Is the configuration of the output similar to the s.e.x. amp -- i.e. - grounded cathode and We split rail bias, or more like a standard cathode bias with bypass cap?

Thanks,

Jim

Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)


Offline Paul Joppa

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Reply #18 on: February 27, 2010, 04:29:32 PM
Is the configuration of the output similar to the s.e.x. amp -- i.e. - grounded cathode and We split rail bias, or more like a standard cathode bias with bypass cap?
I'm moving back to the standard cathode bias arrangement.

The WE arrangement came aboutwith the SEX amp because we wanted to try an autoformer and use it with headphones, so the entire winding, primary and secondary, had to be at DC ground for safety. The WE arrangement allows for that, at the price of requiring two floating high-voltage power supplies. Then when we were developing Paramour II (monoblocks, hence two power supplies already) we realized the same arrangement would allow us to return the signal current loop to the cathode so it does not go through the cathode bypass capacitor. We could not do that before because the stock output transformer is not rated for any DC voltage.

Now that we have an in-house output transformer of better quality and rated for an appropriate DC voltage on the primary, I am ready to give up the WE arrangement and its complications.


Paul Joppa


Offline Jim R.

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Reply #19 on: February 28, 2010, 06:41:44 AM
Paul,

Thanks for the explanation.  I'm not sure I quite grasp it all quite yet, but a little more study of the WE arrangement should make things clear.

Thanks againm,

Jim

Jim Rebman -- recovering audiophile

Equitech balanced power; uRendu, USB processor -> Musette DAC -> 5670 tube buffer -> Finale Audio F138 FFX -> Cain and Cain Abbys near-field).

s.e.x. 2.1 under construction.  Want list: Stereomour II

All ICs homemade (speaker and power next)