I agree.. but one thing is practical operation.. another is when you experiment...eg. change cables or...You know static exceeds the the 2V easy. and can not be ignored..And what if you have gain in a preamplifier.. like a tube amp or something else with gain and great voltage headroom....A practical amplifier must not misbehave too badly even under mistreatment...and clipping
If an amplifier has produces at "more headroom" than the input signal produces it is distorting the signal, you use to get those things in the seventies called dynamic headroom expanders made by dBX and a few others. With digital sources your dynamic range is a fixed quantity ranging from 0 to 2^24, pretty impressive by any standard.
One must design an amp to match that criteria but shift everything up by 30 or so dB without attempting to exceed the rail voltages, else simply expand the rails by a few more volts.
The problem that you mention is very real, when users start inserting gain blocks in between the source and the amp, this poses a real problem and there is no way saying how the remaining system would react. The problem with audio is unlike other consumer products there are no set rules and regulations and leaves it totally open-ended where anyone can do what he basically feels like.
That is the question 😱😱 I even trim the input (10k - on back panel) when I am not around (Kids/ movies) My loudspeakers can not handle 77Vrms. A conventional miller cap will show "spiky" artifacts at clipping , TMC behaved the same a no TMC in that respect.
You should NOT change cables on a amp that can produce 110v p-p waveforms at 2v. I blew a tweeter like this. Nor should you do any probin' in a large 70-80v rail amp that is on and hooked to loudspeakers. I have clipped at the single pair OP/35-45v rail "level" ,and even with loudspeakers , everything survives.
Maybe ... "back to back" 2.1v zeners (2.7v breakdown) at the inputs to be safe on "static" transients ???
OS
Zeners can have 100-300pF junction capacitance. This is also nonlinear. Perhaps diodes or Vbe multipliers could be used as an alternative? Although three 1N4148's in series is just below 2V, which sounds good to me. Another option is to bias an NPN and PNP +-2V from input, so that clamping is variable. Dunno how much it matters, but where there is controversy I prefer to over-engineer rather than under...
A gain of 30 as currently will give 60Vout at 2Vin. This could be changed to 37, for 74V.
What say us?
- keantoken
A gain of 30 as currently will give 60Vout at 2Vin. This could be changed to 37, for 74V.
What say us?
- keantoken
I reckon that theres no such thing as being fail safe...and that you under clipping create something unpleasant...I also accept that disaters will happen once in a while...or everything else will sonically die, in safety solutions and sefetydevices...but as low coloration, low distortion is a part of the design equation.. so must behavior under heavy loads and when over driven...be a part of a well executed design...I know this is at the edge off the topic....I just try to make sure that we don't oversee the majors while optimizing the minors🙂
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Protection
This may be a little bit off topic but I found this information in one of the Telos user manuals: "This amplifier is protected against gray market transshipment. Only the GOLDMUND local official distritritributor can install it for you or the amplifier will stop to functition properly after a period."
What is the purpose of this?
This may be a little bit off topic but I found this information in one of the Telos user manuals: "This amplifier is protected against gray market transshipment. Only the GOLDMUND local official distritritributor can install it for you or the amplifier will stop to functition properly after a period."
What is the purpose of this?
Eeh, you need someone to explain to you what protection against unofficial distribution channels means ?
Nothing new, just ask Krell.
Nothing new, just ask Krell.
They run the zener powered CCS at the max , enabled with a jumper. The authorized dealer/installer clips the jumper , easing the current on the zener. 😀 Without this the amp fries in months. Goldmund sabotages their own equipment to keep the aftermarket $$$ flowing . Do not trust these "audiophool" marketing companies , they are out there to screw,screw,SCREW. Their designs are marginal and they have no honour. I am glad for knowledge and DIY 🙂
With the Telos the "self sabotage" is programmed into the firmware. 🙁
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Unfortunately, the goldmund MM3 thread has been closed...
Eventual builders of the said project would have undoubtly
gave some good insights about what must be improved in this
polemical design...
Eventual builders of the said project would have undoubtly
gave some good insights about what must be improved in this
polemical design...
Well it doesn't seem as if the current design will please everyone... And the specs aren't that great either.
I'm a preparing a Mouser order, and unless there are fantastical shouts of utter agony, I will build the steenking prototype. I would embrace better specs, but I'm told over and over again that specs don't matter much, and that this topology sounds good. Well, I guess I've got to form my own opinions sometime, but it's too early for that.
Great thanks to those who have enabled me,
- keantoken
I'm a preparing a Mouser order, and unless there are fantastical shouts of utter agony, I will build the steenking prototype. I would embrace better specs, but I'm told over and over again that specs don't matter much, and that this topology sounds good. Well, I guess I've got to form my own opinions sometime, but it's too early for that.
Great thanks to those who have enabled me,
- keantoken
Totally unsolicited but...
MY opinion is that ANY topology sounds good, as long as it is done correctly, and that is where specs come in.
BTW, there is something I saw that begs the question:
Kean, how old are you?
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But it still lives here: http://www.diyaudio.com/forums/soli...lifier-i-have-ever-heard-116.html#post2391451, with boards being shipped and people ready to build and test!
If you are not kidding, that reminds me of my brother (who lives in Dallas), and has been doing incredible things since he was young!
Why not study electrical engineering at university.
It seems like you are interested in this stuff so why not continue your studies.
Oy! I'm nearly 30 years older than you! (but the same age maturity wise 😉 )
You know that youth is wasted on the young? Good one, eh - I just made that up 😀