John Curl's Blowtorch preamplifier part II

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Richard, I suspect that they generally don't know that you drive a Bentley,
We do, he tells us about it ALL the time.:p
I first visited him when he was at Oxford and his close associate was Michael Gerzon (one of the most brilliant and idealistic people I have ever met) and I spent time with both of them and their hi fi findings, already well developed over 40 years ago.
MG was brilliant, but all his best stuff has been ignored. Things that could have REALLY improved music in the home.

I care about: What sounds best, not what costs less.
If Bob Harley, editor of TAS, and owner of a similar hi fi reproduction system (we are even using the same ultra-tweeter) is enthusiastic about MQA, then I am going to give it a serious listen.
I hope he is right in his recommendation.
I care about NOT being forced to have MQA only versions. As long as I can buy unmolested versions I am happy. At least now you can demolest HDCD in your own computer.
 
As long as I can buy unmolested versions I am happy.

For what little I really care about I would just like all the bits the mastering engineer saw fit to record, streaming, etc. has no interest here. As an aside betting on things like storage capacity and/or bandwidth hitting a wall anytime soon is a very poor business strategy.
 
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For what little I really care about I would just like all the bits the mastering engineer saw fit to record, streaming, etc. has no interest here.

Me too. I only stream Radio 3 as the bitrate is higher than DAB. But our internet connection here is to be frank, pants.

It is odd/interesting that the highest potential quality is off my server, but the convenience reduces the enjoyment compared to looking at a rack full of records and picking one. I think that is 50% of why streaming doesn't interest me. The other 50% is that I like to own stuff. I almost envy those who just have a laptop and stupify.

Speaking of which, has anyone tried roon yet? I am tempted, but put off by the server requirements.
 
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R
If Bob Harley, editor of TAS, and owner of a similar hi fi reproduction system (we are even using the same ultra-tweeter) is enthusiastic about MQA, then I am going to give it a serious listen.
I hope he is right in his recommendation.

Just to make sure I am not misunderstanding as the internet makes that so easy. On 13th April you said.
When do I ever talk to audio reviewers?

I assume therefore you read a review of his on this and can point us to it?
 
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Richard, I suspect that they generally don't know that you drive a Bentley, I think that Scott is referring to Jack Bybee's Bentley, which he apparently resents as excessive.
I care about: What sounds best, not what costs less.
If Bob Harley, editor of TAS, and owner of a similar hi fi reproduction system (we are even using the same ultra-tweeter) is enthusiastic about MQA, then I am going to give it a serious listen.
I hope he is right in his recommendation.

You know.... you dont have to buy a brand new one..... and no one really puts a lot of miles on them. And, the wealthy ones dont want to buy a used one..... so their resale values drops like a rock. Buy your air/oil/gas filters from CREWE (Original mfr) in England for <$50 and install/change yourself or local garage guy for $20 labor and save your self $3000 over the dealer charge to change oil and the various filters.

JC.... after our telephone conversation on this.... I found the IEEE paper behind MQA.... to IC takes awhile. But it looks like it is starting to happen and more products will have this MQA thing if it is good. Apparently it is good and not all marketing hype.

I think this is the original source of the design ideas and concepts behind it or close to it: http://bigwww.epfl.ch/publications/unser0001.pdf


THx-RNMarsh
 
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If Bob Harley, editor of TAS, and owner of a similar hi fi reproduction system (we are even using the same ultra-tweeter) is enthusiastic about MQA, then I am going to give it a serious listen.

Well, in this day and age we should carefully choose which reviewers we should trust. What if I'm 25 with plenty of cash to burn on HiFi, but the reviewer of equipment is an old phart over 60? :D

Age%2Bhearing.jpg


P.S. Ok, ok, I'm an old phart myself, but the question is still valid.
 
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Don't. There may be someone out there who knows less about digital audio than Harley, but I can't imagine whom that could be. I read a couple articles of his in Stereophile a few years back and just marveled.

A perfect successor to Harry Pearson.
When I used to care about seeing my LTEs in print I would leaven criticism with praise, and that sometimes worked for Stereophile. When Harley was still there he was co-author iirc of a tutorial article that got me aroused in a bad way. I don't mind when people express opinions, but when they lecture to the presumptive unwashed masses while posing as authority figures, it riles. People attempting to understand, and who turn to such material unwittingly, deserve better.
 
The AD797 is a legitimate product.

MQA is garbage with no real technical superiority. Its main goal, as far as I can tell, is to recycle Meridian's R&D and a dead codec that the market already rejected (originally designed for DVD-A if I recall correctly). It's a pure DRM money grab and marketing exercise. It's still worse than lossless high res PCM files.

Since you don't understand digital audio, I am not surprised that you would believe their well-crafted pseudoscience.

Pretty funny, no? And with the number of excellent, lossless compression algorithms around, why sweat it? It's not like 24/96 is buying us much over 16/44 anyhow. (Yes, I'm acknowledging the fact that some new recordings are being done much more carefully, but do their advantages audibly hold with down sampling to 16/44?)

Likewise, unsurprising to see alt-med topics creep into "high end audio".

Bentleys are definitely a luxury good whereas an ad797 is only in certain applications (inside other luxury goods). Shrug. I don't understand this back and forth (or, well, I do but fail to understand what's to gain).

Bcarso-curious what you find out. I'm interested in playing with designs similar to euvl's sen I/V and have a general antipathy to matching.
 
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Well, in this day and age we should carefully choose which reviewers we should trust. What if I'm 25 with plenty of cash to burn on HiFi, but the reviewer of equipment is an old phart over 60? :D

Age%2Bhearing.jpg


P.S. Ok, ok, I'm an old phart myself, but the question is still valid.
If it were only presbycusis (i.e., strictly age-related). But the losses are terrible for those habitually listening to high levels, and there are generations of people thus.

I recently did some work on an audio product and noted that the frequency response was woefully compromised at high frequencies due to the designer having failed to understand the effects of excessive resistive loading on inductive sources. Things were rolling off severely around about 8kHz. The company owner and respected industry figure said he had been complaining about the absence of highs from the beginning. The subjective reviewer said absolutely nothing about this. Measurements were made in a fashion that eliminated the loading effects, so based on those numbers everything was fine.
 
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Are those curve still valid? They suggest essentially no sensation over 8 KHz for most of the crowd here. Maybe true for motorcycle enthusiasts but I certainty get annoyed by high pitched sounds.
This has to be from an industrial-exposure study? Things aren't nearly that bad for people who have taken care of their ears. Unfortunately audio reviewers and recording engineers probably veer toward the excessive exposure set.
 
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JC.... after our telephone conversation on this.... I found the IEEE paper behind MQA.... to IC takes awhile. But it looks like it is starting to happen and more products will have this MQA thing if it is good. Apparently it is good and not all marketing hype.

I think this is the original source of the design ideas and concepts behind it or close to it: http://bigwww.epfl.ch/publications/unser0001.pdf


THx-RNMarsh

Can you provide more on the IEEE paper like a name or link? Every aspect is like HDCD- including dynamic range capabilities (they don't have) HF extension compressed and the code hidden in lower bits. All of this was in HDCD, which got sidetracked by DVDA and DSD, neither of which are more than footnotes today. HDCD also encompassed matching filters on the encode and decode which helps a lot.

When I last looked and when I talked to them about licensing in volume for self powered speakers they had nothing. There was some talk of creating some code but not like they had thought it through. They never got back to me either. It was like high end audio only, not something a big label would waste time on.
 
Are those curve still valid? They suggest essentially no sensation over 8 KHz for most of the crowd here.

Those curves are from one of Harry Olson's books, Modern Sound Reproduction, published many years ago.
Many or most of the subjects were likely military, and had been exposed to high sound levels routinely.
Like many others who have not been exposed to such levels, I have undamaged hearing, even though
having reached 65.
 
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All of this was in HDCD, which got sidetracked by DVDA and DSD, neither of which are more than footnotes today. HDCD also encompassed matching filters on the encode and decode which helps a lot.

.

People are desperately still trying to get DSD to have a future. I've yet to see a understandable reason for it to sound better other than 'sony have put lots of money into it'.
 
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