Well said ocer, and fully agreed. Observing the reality with the limited senses we have (and share), consumed by and fed through a limited biological processing unit ('human'), doesn't guarantee a valid and unconditional true answer.
So, how to pursuit to your better amplifier?
Just visted a live performeance, Ravel's string quartet in F, panoramic 'viewpoint' extremely left (lots of indirect notes).
What's the verdict - what sounds most equal to the five different recordings I own so far?
The Kodaly Quartet sounds most near, most realistic ('Jazz at the pawnshop'-quality).
What system / topology / anything comes close to this live experience?
V-fet's, Hiraga, pretty much sure Pass's (no such amps here often available, but hailed everywhere), so granted - super simple & rock solid design. The obvious (switching) class AB fails to 'touch the sky'. Nearly every if not all of them.
As said before, currently servicing a 4650 and a 5650 in tandem. I'll drop a picture if time permits. (Pilings upon my table.)
So, how to pursuit to your better amplifier?
Just visted a live performeance, Ravel's string quartet in F, panoramic 'viewpoint' extremely left (lots of indirect notes).
What's the verdict - what sounds most equal to the five different recordings I own so far?
The Kodaly Quartet sounds most near, most realistic ('Jazz at the pawnshop'-quality).
What system / topology / anything comes close to this live experience?
V-fet's, Hiraga, pretty much sure Pass's (no such amps here often available, but hailed everywhere), so granted - super simple & rock solid design. The obvious (switching) class AB fails to 'touch the sky'. Nearly every if not all of them.
As said before, currently servicing a 4650 and a 5650 in tandem. I'll drop a picture if time permits. (Pilings upon my table.)
One of the best sounding amps I have is a tube hybrid that uses 12ax7 and 6922 as output stage with npn current boosters.
No NFB sounds fantastic.
Nelson's greatest wisdom is First Watt.
Literally speaking the first watt of any amp is the most important.
No NFB sounds fantastic.
Nelson's greatest wisdom is First Watt.
Literally speaking the first watt of any amp is the most important.
The 5.6k pull-up resistor works well in sim but when I tried it with 240 9240 fet pair it oscillates like crazy. It may be the fets but could also be the weaker turn on drive.
The most common measurement types that amplifiers are tested with are just a subset of what's possible.
There are infinite possibilities with IMD. There was one thread where the author used 12 adjacent semitones, and looked at the spectrum lower in frequency.
Also, the output impedance is 99% of the time referred to as a single "damping factor" value, whereas in actual fact it seems there is a range of different values that is optimal at different frequencies, and this be tested with resistors and an oscilloscope.
What I want is:
A low output impedance at low frequencies where speaker's bass impedance peak is dominant and cone displacement is high. A current source (high output impedance) at high frequencies, where speaker distortion is dominated by things like stray inductance from overhanging voice coils and magnetic memory effects. And 50/50 in the middle.
There are infinite possibilities with IMD. There was one thread where the author used 12 adjacent semitones, and looked at the spectrum lower in frequency.
Also, the output impedance is 99% of the time referred to as a single "damping factor" value, whereas in actual fact it seems there is a range of different values that is optimal at different frequencies, and this be tested with resistors and an oscilloscope.
What I want is:
A low output impedance at low frequencies where speaker's bass impedance peak is dominant and cone displacement is high. A current source (high output impedance) at high frequencies, where speaker distortion is dominated by things like stray inductance from overhanging voice coils and magnetic memory effects. And 50/50 in the middle.
what about measuring impulse respond of the whole system？
I still don't quite understand what a sound texture of smooth or rough reflect on measurements. Many very very large distortions such as speaker and environmental will hardly make sound harsh, but very tiny of some kind of distortion from amp can. (of course the music source itself should be good at first place, cd quality usually sound bad in good amp)
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Context.
Unfortunately, we must always include (almost) all circumstances, conditions:
If I exchange an amplifier, for example, I also exchange all other conditions at that moment. It takes a lot of experience to identify the causes of the audible changes.
For the vast majority of people it already fails with the knowledge of the influence of the loudspeaker set-up.
Unfortunately, we must always include (almost) all circumstances, conditions:
If I exchange an amplifier, for example, I also exchange all other conditions at that moment. It takes a lot of experience to identify the causes of the audible changes.
For the vast majority of people it already fails with the knowledge of the influence of the loudspeaker set-up.
Your description of lacking impact & transparency doesn't at all resemble my experience with the Tokin SITs in my SissySIT R.3 (à la @Zen Mod) which is inspired by Nelson's SIT-3 (thx Papa).
Of course, I'm not disagreeing; your experience is your experience. Just sharing that I was surprised to read your comments. In contrast, my SissySIT is surprisingly dynamic and transparent.
Granted, I may be misinterpreting this to be one of the "simple DIY amps" you mentioned, when you could be referring much more spartan designs.
Still, I also believe that the vintage VFET amps are special and high-calibre. I mean, my Yamaha C-1 is being restored at this moment (by someone who knows his stuff), so I personally understand the attraction. 🙂
I mean full range speaker usually means lacks impact and transparency. Just to put two extreme end of the variation Spectrum.
Huh? I have a number that are fine in that respect. Especially good at transparency.
dave
Speaking of FRs, I've been heavily considering the Zu Union 6 Supremes as my next speaker upgrade. Partially due to my wife's affinity to their aesthetic (compared to other options.)
I'd be curious to know if anyone here has tried them? I feel like they'd likely pair quite nicely with these lower powered SIT amps (as well as Firstwatt).
I'd be curious to know if anyone here has tried them? I feel like they'd likely pair quite nicely with these lower powered SIT amps (as well as Firstwatt).
Yes that would probably be good. Feedback in power amp control output impedance....How about a frequency dependent circuit/filter in the feedback loop of the amp - that would give you exactly this - no?
//
Waiting for shipping
Hitachi ha-500f
Might be the worst sounding vfet amp according to information in forums.
I will verify that.
I also heard modding will make huge improvements. I will test that also.
don't pay too much attention on information on the forums. Listen to it and tell us how it sounds in your system.