But that is just the amp. I was saying a complete high end (or hi-fi if you prefer) a few k. Speakers always cost a little to get good performance.
the fact that a lot of people who do serious engineering or science for a day job and dabble in things they know to be a frippery a night does suggest no one can be Dr Spock 24 hours a day 🙂
Mr Spock, unless you are referring to the famous pediatrician Dr. Benjamin Spock, to whose book Baby and Child Care my late father frequently referred and followed.
It's maybe OT, but related to your reference to GPT's tricks with recorders, some traditions actually do the same thing with roughness. This is good
https://www.youtube.com/watch?v=fGlnRahtqM0
Understand. Sadly many of the people who right about audio for a living (or discover the next best thing on some of the other forums out there), don't. Given that nearly all surround receivers have complex eq and room correction in there is a good case for the fact that the average movie buff has higher fidelity than the average 2 channel guy!
Thank you Bonsai, some potentially real practical contribution to the discussion! I had a look at your designs a while ago and they look interesting, and good on you for putting them in the public domain. Because of this and many interesting observations you've made in the past I always read your posts carefully. Care to discuss any thoughts you have as to subtle differences in sound between say the low-feedback amp and the ultra high performance amp? If this goes against your principles, have you had any friends/associates listen to or build your amps and compare them who are less shy/skeptical about listening for SQ differences?
Thank you Owedo.
It's very difficult for me to comment and the views are entirely subjective. Interestingly, my eldest son has been pushing me for about two years to build a switching and line leveling box so we can compare the different amps. Out of all the amps, he was most struck by the sx-Amp playing on my B&W's. It was a very good recording (Yo-yo Ma).
The sx-Amp is about 28W peak class A into 8 ohms (1,4 A bias current and runs HOT). It also has the highest distortion. I should add that he trained as a recording engineer, is a good musician and has had plenty of exposure to all sorts of very good equipment. The point is, chasing low distortion as a FOM wrt the 'sonic experience' is not the answer. However, neither is sloppy engineering so just slapping stuff together is not acceptable.
Without a doubt, speakers and room interaction are the biggest contributors to overall sound.
It's very difficult for me to comment and the views are entirely subjective. Interestingly, my eldest son has been pushing me for about two years to build a switching and line leveling box so we can compare the different amps. Out of all the amps, he was most struck by the sx-Amp playing on my B&W's. It was a very good recording (Yo-yo Ma).
The sx-Amp is about 28W peak class A into 8 ohms (1,4 A bias current and runs HOT). It also has the highest distortion. I should add that he trained as a recording engineer, is a good musician and has had plenty of exposure to all sorts of very good equipment. The point is, chasing low distortion as a FOM wrt the 'sonic experience' is not the answer. However, neither is sloppy engineering so just slapping stuff together is not acceptable.
Without a doubt, speakers and room interaction are the biggest contributors to overall sound.
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Engineering and understanding lets you push things forward. Gives you tools that can help you in the direction you choose.
What people seem to forget is that >10% THD will always sound awful and <0.001% THD will always be inaudible regardless of the distribution of the spectrum non-linear distortion products. 0.001% is -100dB so if you are listening at anything below 100dB SPL all the distortion products are below the threshold of audibility. It's not hard to design an amplifier which has inaudible distortion for a practical power output range.
Where more information about the spectrum is required is in between those ranges where distortion is audible but not strongly unpleasant - i.e. ~0.1%-1% THD.
The other problem is when the THD is only quoted at one power output level - that tells us very little about the level of distortion for dynamic signals. It can be deceiving to quote 0.01% THD at 100Watt if it's 1% at 1Watt. Likewise an amplifier 10% THD at 100W could be 0.001% at 1W and 10W while another amp quoted as 0.3% THD at 100W could be 0.3% at 1W and 10W. The one which looks worse on paper (10% @ 100W) is probably a better amplifier for practical home HiFi use since it is cleaner at low power.
Such subjective observations such as 'image' and 'depth' are merely a grouping of the various objective qualities of a system.
e.g.
'This tweeter sounds harsh' could mean 'This tweeter has an awful peaking frequency response' or 'this tweeter has horrible levels of 3rd and 5th order distortion' or 'i'm used to a tweeter which rolls off hard at 10kHz so any tweeter which is flat to 20kHz sounds harsh to me'.
'This system has great imaging' could simply mean 'this system has flat frequency response, low non-linear distortion and the levels of the left and right speakers match well'.
'This system is lively and engaging' could mean 'this system has a rising response which I prefer because I have hearing loss above 5KHz' or 'this system has high non-linear distortion which I am currently enjoying as false detail but in 2 hours I will perceive as distortion and listening fatigue'.
The problem is that it is very difficult to demonstrate such subjective descriptions of since they are broad and often are used to describe multiple unrelated technical deficiencies of a system. The ear is easily fooled and multiple unrelated sources of distortions can often manifest themselves as the same type of subjective sound even though they measure very differently. The best advice I can give is to invest in a measurement setup and try to correlate the measurements to what you hear. Then you will hear what linear and non-linear distortion issues sound like and be able to describe issues without resorting to using vague non-technical jargon like 'harsh' or 'depth'.
Measurements are also important to prevent expectation bias when making either scientific or unscientific changes to a system.
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Wow! This post is one of the best I've read here for a very long time.
I wish I'd made it. Thank you.
Jan
I wish I'd made it. Thank you.
Jan
a list of ambiguous and misleading terms?
Indeed a nice summary of important details.
I was given a link yesterday to an open-access journal article about terms in psychology that are problematic, some fifty of them (a long article!), and it struck me that something comparable should be written for audio, probably not nearly as long or as thoroughly referenced, but touching on some of the words TMM and others mention, like "image" and "depth". One of my raised-eyebrow ones is "sonic signature", but then there is "pace, "rhythm", "slam"...
And "linear". So many use it but I suspect few when pressed know how to define it.
Maybe a little historical sidebar about William of Ockham?
My remark to the friend who provided the link was that I could acquire a whole new set of haters 😀
Indeed a nice summary of important details.
I was given a link yesterday to an open-access journal article about terms in psychology that are problematic, some fifty of them (a long article!), and it struck me that something comparable should be written for audio, probably not nearly as long or as thoroughly referenced, but touching on some of the words TMM and others mention, like "image" and "depth". One of my raised-eyebrow ones is "sonic signature", but then there is "pace, "rhythm", "slam"...
And "linear". So many use it but I suspect few when pressed know how to define it.
Maybe a little historical sidebar about William of Ockham?
My remark to the friend who provided the link was that I could acquire a whole new set of haters 😀
That's about the size of it. Oh, and the human brain part of the equation of course. 🙂
Sometimes we talk as if humans all perceive things equally. We know they don't, right?
Sometimes we talk as if humans all perceive things equally. We know they don't, right?
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