Goldmund Mods, Improvements, Stability

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It seems , it is an instant "thumbs down" at this site ... New procedure for requesting membership registration

....read at bottom (I saw it here first) :cool: :D

OS

*GEB = "Golden Ear Brigade", meaning advocates of such things as cable burn-in, resistor directionality and countless other things that have no basis in physical reality.

WHAT - now the cat is outta da bag - I've been **'n people about resistor directionality fer YEARS!!!! Hmmmmmm.......... Andy C was here for quite awhile and most likely is uninviting me and my sense (or lack of it) of good fun. It wouldn't be the 1st time I missed making the "A" list........ :D
 
*GEB = "Golden Ear Brigade", meaning advocates of such things as cable burn-in, resistor directionality and countless other things that have no basis in physical reality.

WHAT - now the cat is outta da bag - I've been **'n people about resistor directionality fer YEARS!!!! Hmmmmmm.......... Andy C was here for quite awhile and most likely is uninviting me and my sense (or lack of it) of good fun. It wouldn't be the 1st time I missed making the "A" list........ :D

Then there are the things that CAN be heard ... larger power supplies , more headroom (higher rails), even different designs will have their own distinctive character. Cap multipliers will absolutely heighten the stereo image .. as an example. No GEB for me , but there are audible improvements that can be enabled by design.
You can also see these things on both simulator AND CRO... so they will effect the resulting sound. I once thought "an amp was an amp" until recently with the ability to hear 3 different ones on the same output stage in the course of an hour. :eek:

OS
 
Anthony, I am not suggesting that this is the cure to the 7815 problem, but since you say this is a notorious for this particular the amplifier, using a diode across the in/out of the regulator biased in the direction so that the output cap can discharge bypassing the regulator. This problem may only occur once in a blue moon, but it can. In fact a very cost effective precaution.
 
Ost Kris & Kean,
can the Mongrel physical size be adopted for this amplifier output stage?

That way we can use any of the Mongrel output stage with a gold input stage and we can use any input stage with the gold output stage.
Any combination we think might be worth listening to !

Some of the 6pins linking output to input will be redundant if a separate supply is fed to the input. I would keep all 6pins on all PCBs and use a removable link between two pads to cut off the Output fed power supplies to the input PCB.
 
Ost Kris & Kean,
can the Mongrel physical size be adopted for this amplifier output stage?

That way we can use any of the Mongrel output stage with a gold input stage and we can use any input stage with the gold output stage.
Any combination we think might be worth listening to !

Some of the 6pins linking output to input will be redundant if a separate supply is fed to the input. I would keep all 6pins on all PCBs and use a removable link between two pads to cut off the Output fed power supplies to the input PCB.

Absolutely , Now that I've "standardized" with sprint layout AND have a handful of power Mosfets now , a Board will follow. Unfortunately , I tried my version of the GM and ended up with a oscillator (fried a zoble). I took out the BE and it worked. I now subscribe to nico's vision of simplicity and will most likely just make a goldmund clone with "simple" 4 transistor VAS , plug it in ... be happy. :) As far as small , there is always partial SMD. I put the 2 fastons and a cap multiplier on the power board for separate PS's .. break the jumpers (below)... proven and practical. I already have taken some of my voltage stages and juryrigged them to my to-3 laterals , they sound wonderful !
You can listen to all the combinations in minutes , amp heaven.
BTW , I even use the "diode" (reverse bias protect) on my multipliers. The voltage boards are so efficient that the output cap on the multiplier will stay charged reverse biasing the transistor , same as what would happen on a 78xx without the diode (they are in the picture near the trannies)
OS
 

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Also in what form Electro-Mechanical connections should the input(110/220vac) and the outputs plus and minus voltage with a ground be? Wires, OS type connectors or what?

For lower current (5a and under) 3 position euroterminals ,for 5 and up to 20A the faston is the most economical way. They do make "monster" euro terminals but they cost a fortune ... fastons like mine 63066-1 Tyco Electronics / AMP Terminals
just need an 1/8" hole and cost $.16. For AC or something that needs a lot of clearance (HV) the faston is also the best choice.
apiece.

Krisfr , isn't that KT's regulator on the board ?

OS
 
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