Krisfr, what is a GM(TBAIEH)?
GM(TBAIEH) - Google Search
I entertained the thought of using a joule-thief type supply for the frontend. That would be neat!
- keantoken
GM(TBAIEH) - Google Search
I entertained the thought of using a joule-thief type supply for the frontend. That would be neat!
- keantoken
TBAIEH - another acronym ? What we would always describe our creations as or just another banner for the "golden ear brigade" ? 😀
OS
OS
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) 😎 😀
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........ 😀
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. 😱
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.
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.
could the 7815 be driven over voltage at start up due to discharged caps appearing as short circuits?
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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If that is a cap multiplier, you should make it a star ground as much as possible. Avoid the circle around the board type.
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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ok
what is the wattage on the .39 R1?
are all of the OTHER grounds besides the one coming of the collector of Q7 tied together and to the common of the input voltage transformer?
