Goldmund Mods, Improvements, Stability

In the mean time I am going to build both of these and look forward to Alex MM finishing up the amp board.
I want to put the mouse down and pickup the soldering Iron.
I need to polish up my PCB fabrication skills for drilling holes.
A friend is sending me a 5 and half Keithly meter, I can hardly wait this cheapy 3 is okay BUT 5.5 is serious.

I got too many parts I just bought sitting around:D
 
Hey Keantoken:
Can you post what ever your current iteration of the shunt that you have or at least direct/point me to it.

Kbeist:

I am using Sprint-layout, it is good for prototyping which is what I am doing. :D

If anyone else wants to build along just let me know and I will post the pdf:cool:
 
What is better than a Goldmund?

I am finalising tweaking on the new ELD2 at low voltage. Power rails runs from +- 70VDC, and pre-driver runs of series shunt regulator to supply +- 87VDC to pre-driver stage. Slowly getting ready for commercialisation. That is when the work starts in earnest. Launch will be by April. It is fantastic sonic performance and we think a winner among winners, Lot of mechanical development to be done.

The topology shares some ideas found here so I wish you all the luck to produce an amp of impeccable quality, I managed to,


Compliments of the season.

Nico
 

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The amp is fast, there is absolutely no hum or hiss connected directly to my HD800 not even a hint of hum, Very high slew rate 139V/uS and bandwidth around 480KHz. Moderate undistorted power output is claimed at 280 watt into 8 ohm.

This was my task for the holiday season. It was really enjoyable and the fruits are there for the eating.
 
I am finalising tweaking on the new ELD2 at low voltage. Power rails runs from +- 70VDC, and pre-driver runs of series shunt regulator to supply +- 87VDC to pre-driver stage. Slowly getting ready for commercialisation. That is when the work starts in earnest. Launch will be by April. It is fantastic sonic performance and we think a winner among winners, Lot of mechanical development to be done.

The topology shares some ideas found here so I wish you all the luck to produce an amp of impeccable quality, I managed to,


Compliments of the season.

Nico

VERY NICE , Nico. I see we share the same layout style and design philosophy. I know you "build what you preach", as do I (below). I am already selling mine locally and have moved beyond endless simulations. Is that a 8 OP lateral or BJT ??

Amp below 3 months old and survived new years party , enough test for me. :) Next is the original goldmund and the leach to perfect. I am curious to see whether they can "better" the blameless's. :D
Ps , nico .. if you can send me the IPS/VAS , I too can audition it. Unless it is IP.
OS
 

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New Years test bench ... Controversial Power Amp at final measurements. :)

View attachment 203818 View attachment 203819

There will be new amps on the market as seen here, only the thread topic still missing ... stucked on shunts. :D

Nice PS ,man , You did get it working ?? A better man than me ... I ended up with oscillation. :( (Looking at this will only make me redo the CX once again - I don't give up). Why not the original with a better 2Q CCS.... easy to do. Then there is Artu's amp ... it has the same FFT profile and slew as the goldmund with 10X the performance. Just like walmart , too many choices. :D

Wow , point to point on a veroboard !!

PS . thats why I suggested the shunt be separate , FINISH the amp ... work on the PS later.
 
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Nice, now what did you remove to make it work... :D

I have 3 amps that I might be able to fix, I just replaced a bunch of bad coupling caps on a Pioneer tube receiver, sounds like crap so it probably still needs some work... Then I have a Denon 588 with a bad 7815, and then a possibly unrepairable H/K AVR35 with corrupted display. I will try to make those wait until I've figured out exactly how to wire together our amp. Lazy, could you post a picture of your wiring so I have some ideas on how to start?

- keantoken
 
VERY NICE , Nico. I see we share the same layout style and design philosophy. I know you "build what you preach", as do I (below). I am already selling mine locally and have moved beyond endless simulations. Is that a 8 OP lateral or BJT ??

Amp below 3 months old and survived new years party , enough test for me. :) Next is the original goldmund and the leach to perfect. I am curious to see whether they can "better" the blameless's. :D
Ps , nico .. if you can send me the IPS/VAS , I too can audition it. Unless it is IP.
OS

Hi OS, yes IP applies but I will give you some clues, you will figure it out. First pair of power transistors are lateral mosfets running class A to 8 watts, followed by three pairs BJTs running class B (the final amp will have 4 pairs), hence mixed technology, call it IGBT if you like. Pre-driver stages are stabilised by my simple series shunt regulator that I showed early in the thread at 18V higher than output rails so MOSFETS can be driven to rails.

No latch-ups, no funnies, -3dB bandwidth extends to 480kHz, phase marging 42 degrees at 0dB, THD lower than anyone can hear, power adequate to drive realistic volumes in a large livingroom, it is dead quiet and I can listen on it with my HD800 cans, when nothing playing you will not know wether the amp power is on or not.

Have been working on it since October, tweaking changing this fiddling with that, measuring, listening changing, you know the story. Sounds stunning.

Now I have to start the mechanical and assembly drawings, final PCB layout to incorporate all the hack and tack stuff. Boring but necessary. Problem is I should have been on leave not working, but my job is also my hobby.

Kind regards

Nico
 
First pair of power transistors are lateral mosfets running class A to 8 watts, followed by three pairs BJTs running class B (the final amp will have 4 pairs), hence mixed technology, call it IGBT if you like.
Sounds familiar ... for quite some years. :cool:


No latch-ups, no funnies, -3dB bandwidth extends to 480kHz, phase marging 42 degrees at 0dB, THD lower than anyone can hear, power adequate to drive realistic volumes in a large livingroom, it is dead quiet and I can listen on it with my HD800 cans, when nothing playing you will not know wether the amp power is on or not.

Have been working on it since October, tweaking changing this fiddling with that, measuring, listening changing, you know the story. Sounds stunning.
Looks we have another "The Very Best Amplifier I Have Ever Heard!!!!" here. :D
 
Just thinking, is there any way, knowing this stuff without a formal education in electronics, is there any way that my first job could be more than burger-flipping?

- keantoken
If you're interested in computers you'd probably make a good programmer. I don't know how much demand there is these days for programmers / web developers / network geeks etc on your side of the planet, but the entry barrier for that kind of thing is probably a lot lower than for anything related to circuit design.