Goldmund Mods, Improvements, Stability

Kean, formal education does not make you knowing it. Formal education will teach you basic theory some of it useful some not, it teaches you how to interpret and solve a problem, if you need it you will know it exists and figure out how to apply it.

Knowing comes with experience only. The day you die is when you know the most you ever did.
 
best amps I have ever heard, and owned, always amps with relatively low output

never heard a big amp that was more than just ok

I have, but those are the exceptions. Normally big amps have problems in the HF distortion (mostly of the IM type, especially coming from the power supply).

I stopped believing in reviews long time ago, but i will never stop believing to my ears, which do NOT like 2% or even 0,5% second harmonic, as well as they dont like lots of little higher ones (especially coming from crossover).

Little amps on the contrary may sound mellow and relaxing, but they dont have the dynamics, they dont have PRAT. I want to enjoy the music, not to fall asleep.
 
5) My opinion on paralleling devices – for output stage, it’s inevitable. Anytime you do that, it’s bound to compromise the “coherence” somewhat, as individual devices are simply individuals (not the same). This is analogous to paralleling 300B in a SE amp. You trade the magic for the power.

I'm not that negative on paralleling, unless you are using a single-ended output stage with a SINGLE transistor and not a push pull and therefore true class A operation. In all other cases, you are using a minimum of two devices, making them four I dont think it will worsen the sound, especially if the devices are matched, but this is not required where there is lots of NFB, like in this design.
I'm afraid you could enjoy that second harmonic of SET too much ;)
I'm in the minority that prefers a less distortion design most of the times, as long as the specrum is clean and decreasing.

Contrary to intuition, high gm on the input stage is bad for SR and stability. This is where JFET comes in handy.

I disagree. See Ayre designs.
 
hmmm....I for one have used Golmund..quite allot for demonstration purposes...It's good.. but I must say not all is superior..... mids and highs are soft and silky.. but the buttom...lacks the grip an untter control that is clearly present in other designs..in that aspect they sound like what they are mossfet amplifiers...

No single amp will be "the best" in all signal spectrum.
PERIOD.
Some characteristics required for improving the low bass conflict to those needed to have "silky soft highs" (=not tymphanys drilling).
Any design chooses their middle point and people like it according to their preferences.
 
As for Hitachi s lateral fets, whoever did build a worthy
design using them , probably didn t went back to bipolars.
Hope that you ll have soon an occasion to test them.

You guys are really tempting me in trying them on my design (soon to be) :)
I've never like (the sound of) mosfet amps, but I dont know if I have listened to one using (well) hitachi laterals. I haven't heard the Mimesis, for once.
 
Hi Telstar,

I have until about twenty years ago only designed with BJTs, I then did a design using Hitachi Laterals and have never gone back to BJTs, they have a lovely sound, but the downside is less power for the same rails. If you can live with that I am sure they will find a place in your audio system.
 
Hi Telstar,

I have until about twenty years ago only designed with BJTs, I then did a design using Hitachi Laterals and have never gone back to BJTs, they have a lovely sound, but the downside is less power for the same rails. If you can live with that I am sure they will find a place in your audio system.

Have you tried the NJW parts (the thermaltraks)? They sound good to me.
But I also found out that another amp in my reference list use the highly praised "verticals with lateral behaviour" 2SK1530 from toshiba. Hitachi laterals can only sound better.
My issue is that i have to make 3 amps of different power from 15 to 200W for a multiamped system and using the same output devices gives a better unity of timbre, for lack of better words.

In the end i think i'll try two ouput stages, one with my NJW and the other with the laterals used here with either hitachi or the magnatec parts (which according to Charles Hansen are supposed to be superior, although he doesnt make model numbers).

Did you guys notice that Magnatec is going to release NP matched laterals in single die (only plastic heheh)? I asked them when they'll be available.
Magnatec. ALFET Lateral MOSFETs