Music or speech signals are asymmetric, we all would agree on this, but with zero dc component when integrated over several periods. Have you measured any special capacitor distortion with asymmetric zero dc waves? Of course LF or HF filter roll off not to be confused with distortion. (Please do not mention Hirata distortion here as an answer).
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By the way, the opinion that signal created from sine waves must be symmetrical is completely wrong. Attached is the signal that contains only 3 sine waves. Basic harmonic, 2nd and 4th. It is assymetric, + amplitude differs from - amplitude and dc is zero.
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Jan,
You are so correct, leave out industrial design changes over time and most products just loose out over time to those who stay current or lead the charge. That is why I am thinking that surface mount devices and even smaller smps will be something that will lead the changes in newer consumer electronics. If you can supply the same or better sound in a smaller and more elegant package you will draw notice. It may not be something that the DIY crowd want to take on but I don't see how a consumer products company can ignore the size reduction and great looking design.
You are so correct, leave out industrial design changes over time and most products just loose out over time to those who stay current or lead the charge. That is why I am thinking that surface mount devices and even smaller smps will be something that will lead the changes in newer consumer electronics. If you can supply the same or better sound in a smaller and more elegant package you will draw notice. It may not be something that the DIY crowd want to take on but I don't see how a consumer products company can ignore the size reduction and great looking design.
It's all about differentiating your product from the competition, and price erosion. If you can convince your target customers that you have achieved a breakthrough in amplifier design that allows this amplifier to sound as if you are there, that's a real advantage in the market place.
You CANNOT do that with better sound reproduction because there is no way you can let your potential customer hear it. But you often CAN convince them with a well-designed ad campaign, especially if it suggests that if you have this amp, girls will flock to your listening room. And we all want girls flocking to our listening rooms, don't we? Or boys - take your pick.
Study car advertisements and commercials on TV. Try to note what it is they are saying, and what they are implying. Look at the visual sequences. A great educational experience.
Jan
You CANNOT do that with better sound reproduction because there is no way you can let your potential customer hear it. But you often CAN convince them with a well-designed ad campaign, especially if it suggests that if you have this amp, girls will flock to your listening room. And we all want girls flocking to our listening rooms, don't we? Or boys - take your pick.
Study car advertisements and commercials on TV. Try to note what it is they are saying, and what they are implying. Look at the visual sequences. A great educational experience.
Jan
Wet tantalums belong to the most expensive parts. Some can cost several hundred $. Vishay - Capacitors - Wet
They are used in the high tech industry when minimum leakage is the goal.
I do not think that Naim uses tantalums in the direct signal path any more.
Many makers though use Tantalums for PSU decoupling. Not only Naim.
I never use them but some may have good reasons to do so.
They are used in the high tech industry when minimum leakage is the goal.
I do not think that Naim uses tantalums in the direct signal path any more.
Many makers though use Tantalums for PSU decoupling. Not only Naim.
I never use them but some may have good reasons to do so.
Hi,
75% marketing, 25% product value, right?
Sure enough, most people are just plain silly.
Which also brings us back to your statement earlier on that since Naim amps sell they must be doing something right....
I assume you did not mean good sound but rather good marketing?
I think, as far as Naim is concerned that they filled a niche back in the Nineties when low efficiency LSs needed some hefty current to wake up.
They never convinced me though as simple mods to the PS brought them easily to higher levels but still overall underwhelming.
Not to mention the " use our cable or it won't work" propaganda...
Really?
Ciao, 😉
75% marketing, 25% product value, right?
Sure enough, most people are just plain silly.
Which also brings us back to your statement earlier on that since Naim amps sell they must be doing something right....
I assume you did not mean good sound but rather good marketing?
I think, as far as Naim is concerned that they filled a niche back in the Nineties when low efficiency LSs needed some hefty current to wake up.
They never convinced me though as simple mods to the PS brought them easily to higher levels but still overall underwhelming.
Not to mention the " use our cable or it won't work" propaganda...
Really?
Ciao, 😉
Naim now with Focal works hard on amplifiers that can drive that kind of speakers.
The old Naims could not drive the Focals well so we will see a lot of new stuff coming.
The big reference dog is just a comet on the horizon.
The old Naims could not drive the Focals well so we will see a lot of new stuff coming.
The big reference dog is just a comet on the horizon.
Jacco,
Can't say I've looked in a current audio magazine for awhile, not even sure how many are left here in the States? Last I looked there weren't many at all, most of what I saw were really expensive mags from Europe. I guess I have some catching up to do!
Can't say I've looked in a current audio magazine for awhile, not even sure how many are left here in the States? Last I looked there weren't many at all, most of what I saw were really expensive mags from Europe. I guess I have some catching up to do!
I implied single sine wave test signals..... Multiple sine waves is another story.... I invested in A-P primarily for its multi-tone analysis. To see what a whole music system looks like... rather than one piece in isolation... just out of curiosity.
Or, what if you had a signal that had zero DC but was asymetric like this....... maybe a high level positive pulse of short duration followed by a suitably wide low level negative pulse... as one cycle. How do power amps response to that by topology or other? Will some differ when the polarities are reversed?
THx-RNMarsh
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Vacu,
Have you ever measured this , decades and i have never seen VC temp as an issue with domestic speakers using relative decent drivers ( never measured cheap crap ) this is really an issue when doing sound reinforcement.
IMO this is a non issue in domestic operated speakers, operating close to the voltage rating on xover caps is a bigger concern with heat and distortion...
I agree, and I include cheap drivers, 😛, in the basket. I've spent many years driving domestic speakers hard, for long periods of time, with nil apparent effect - voltage sag and overheating in the amps has caused abberations; only in the PC speakers I have is it audibly noticeable that possible softening of the adhesives from heating has caused slight rub issues.
Do this [from your arb waveform gen] and run it into amps of all kinds --
View attachment Asym signal.pdf
THx-RNMarsh
" . . . .only in the PC speakers I have is it audibly noticeable that possible softening of the adhesives from heating has caused slight rub issues. "
Is your reference system, Frank?
😀
Is your reference system, Frank?
😀
I think you've asked me that before, 😉 ...
The PC's getting a rest at the moment, I've been movin' on - the latest plaything is a good quality 20 year old plus keyboard synthesizer, and I'm curious what can be achieved there. Inbuilt speakers, 10W(!) amplifiers per side, it can do an acoustic piano well enough to fool many, 😛. But I'm aiming to build up to full blown orchestra and band material, see how it goes.
An interesting aspect is that the recorded samples, of the piano at least, appear to only have a 12 bit depth to them; I remember that I found out from some source way back about that. Which means, at high volumes levels close by you can hear the quantisation noise in the waveform decay - a subtle zzz'ng sound ... not really a disturbing problem, but quite apparent if you listen for it ...
The PC's getting a rest at the moment, I've been movin' on - the latest plaything is a good quality 20 year old plus keyboard synthesizer, and I'm curious what can be achieved there. Inbuilt speakers, 10W(!) amplifiers per side, it can do an acoustic piano well enough to fool many, 😛. But I'm aiming to build up to full blown orchestra and band material, see how it goes.
An interesting aspect is that the recorded samples, of the piano at least, appear to only have a 12 bit depth to them; I remember that I found out from some source way back about that. Which means, at high volumes levels close by you can hear the quantisation noise in the waveform decay - a subtle zzz'ng sound ... not really a disturbing problem, but quite apparent if you listen for it ...
Well, I built another amp today. It worked the first time, and exactly as I had predicted! With much help from the simulator of course...
This latest one is technically no worse than my previous ones, and far better below 10KHz. It shows promise to be not only the most linear amp I've ever designed, but also the safest and most stable. I'm using a compensation scheme that allows the volume control (2x to 20x gain) to be directly in the feedback loop which allows keeping noise below 100nV/rtHz, while the amp is stable throughout the volume range, just slower at higher gains.
What's funny is that while this and most of my other amps test to be stable into speakers based on my 100MHz Tektronix scope, They still usually come into being having sharp sibilance that drives everyone from the room and makes 80% of my music unlistenable.
This problem always drives me mad. It behaves perfectly on the scope but has all the audible appeal of pepper spray. Oops, change of marketing plans.
I will construct an attenuator to inspect the output with Baudline, hopefully that will give me an idea what went wrong.
This latest one is technically no worse than my previous ones, and far better below 10KHz. It shows promise to be not only the most linear amp I've ever designed, but also the safest and most stable. I'm using a compensation scheme that allows the volume control (2x to 20x gain) to be directly in the feedback loop which allows keeping noise below 100nV/rtHz, while the amp is stable throughout the volume range, just slower at higher gains.
What's funny is that while this and most of my other amps test to be stable into speakers based on my 100MHz Tektronix scope, They still usually come into being having sharp sibilance that drives everyone from the room and makes 80% of my music unlistenable.
This problem always drives me mad. It behaves perfectly on the scope but has all the audible appeal of pepper spray. Oops, change of marketing plans.
I will construct an attenuator to inspect the output with Baudline, hopefully that will give me an idea what went wrong.
A audible degradation due to the V/I characteristic of a capacitor that can not be measured? This opens the door to just about any claims made here. BTW your signal (any signal) when repeated, decomposes into sine waves and the asymmetry manifests as seconds. If you apply non-bandlimited signals to an amp and drive it into large signal misbehavior that is assymetric you might learn something but it might not be useful.
John might remember that I used Peases' article and SPICE to generate models for some of the "bad" DA capacitors and could reduce the error signal to an arbitrarily low level, i.e. the DA was a totally linear time invariant effect modeled as an R/C ladder network.
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