John Curl's Blowtorch preamplifier part III

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Happy Fourth Everyone!

........meanwhile the debate continues.
 

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None what so ever..... we heard the same quality and affects regardless of level.
Same quality and affects, meaning that they sounded same?
yep,. No interest in hiding which was which. Only listening to them and their each unique sound quality.

Pls do ... never mind.
Thank you for confirming, especially a delight to T's tirade at me.
Let me guess, level unmatched and sighted listening comparison.
Sorry to say this, but you are insulting somebody which is a lot more equipped, passionate and experienced in measurements than you seem to be and will never be.
Not to say that you are boring like a striped record of a Lady Gaga fanboy, which you clearly share the mode of intellectual functioning.

If I can give you the advice of an old Indian, remove your filter of odd harmonics and your prejudices about things and people.
 
Because you are both agreeable, you both heard the same character differences of each DAC.

You have a container load of measuring equipment. It is not criticism but serious bewilderment. This is your opportunity to, perhaps, correlate something you can hear with something you can measure.....and you miss the opportunity.
 
What would be nice is if there was an universally accepted language, ie terminology, that was tied to the measurements.
Toole and Olive (you know, the people you aren't interested in reading), amongst others, have done a lot of work in that area. It does mean though that people have to agree to use the terminology, can you really envisage that ever happening? Can you imagine Dan, for instance, not just using his own regardless?
 
This literal feedback contaminates the playback, but it is a subject seldom addressed. Given the magnitude of the feedback with many TTs in many homes, I believe it swamps many of the other distortion mechanisms associated with vinyl.

An observation from the past

When I was young, with some friends we run a test on some spring suspension TTs to see which one was more immune to acoustic -via air- feedback. Speakers over pillows on the concrete floor, 1m away from and facing the TT. Opinion made from real-time audition and later play back from a cassette (via tape-out) event recording.
Winners: 1) Empire 598, 2) B&O Beogram 1500, 3) Phillips either 208 or 312 I don’t remember, 4) AR XA, and below these the Thorens TD166, TD 160, Ariston RD11, Dual 503. (all lids were raised)

I remember the owner of the Ariston had to go and buy the beers after the event, as he lost his own bet being very confident of the superiority of his TT upfront.😀

George
 
Because you are both agreeable, you both heard the same character differences of each DAC.

You have a container load of measuring equipment. It is not criticism but serious bewilderment. This is your opportunity to, perhaps, correlate something you can hear with something you can measure.....and you miss the opportunity.

Lots of room for conjecture and guessing and assumptions.

The person doing the changes has done those tests and came up with this solution. He used his own spectrum anal (his goes out to 2 GHz). I see no reason i need to redo everything others do. He did it, and I wanted to hear the result... if I could.


Mark and I have differences sometimes but it is not in what we each hear. We hear the same things.

More shielding and absorption of HF signal which are field coupled into analog appears to make some difference.

But, like I said the larger detectable difference is from analog source vs digital source.



THx-RNMarsh
 
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Toole and Olive (you know, the people you aren't interested in reading), amongst others, have done a lot of work in that area. It does mean though that people have to agree to use the terminology, can you really envisage that ever happening? Can you imagine Dan, for instance, not just using his own regardless?

I’ve read tooles ‘loudspeaker measurement and their relationship to listener preferences’ 1 and 2 ....

It said nothing but the obvious.

My time is better spent doing my own subjective testing......i think I’m going to study that Delta ‘sound wheel’ a little more, at least I’ll be able to start my subjective findings with ‘the sound wheel evaluation results are’..... 😀
 
An observation from the past

Winners: 1) Empire 598, 2) B&O Beogram 1500
I remember the owner of the Ariston had to go and buy the beers after the event, as he lost his own bet being very confident of the superiority of his TT upfront.😀

George


Interesting, I can scarcely imagine two more (visually) different turntables! Also, the Beograms that I have seen have rather stiff, low-travel suspensions. It just goes to show there are a lot of details to account for.
 
I was trying to explain what 'transparent' amp is (which I'm sure most people have never heard). The issues that can brutally exposed is not the kind of clanging aluminium sound, or lower resolution due to compression. One common issue is too much reverberation information. This also unlike clanging aluminium, can sound 'nice' to some, but not to me. Here is a recording which has too much room reverberation (if your amp cannot produce it, just see the room condition in the video). Natalie Merchant's Motherland:
YouTube

Here's something I came across in a review of an amp showcasing Bruno Putzey's Purifi's new class D amp module 1ET400A & it has relevance to what you said above about too much reverberation in a recording
>My first buffered sessions concluded that the Purifi tech was really in the service of a more natural sound. Though extremist 'philes will miss the message when phrased in such casual fashion, the Purifi amp demonstrated easy listening at a very high level. This meant that I could enjoy certain very personal guilty pleasures like Wael Jassar's Fi Hadret El Mahboub album. Its over-produced Pop gloss, excess reverb and compression all score entirely the wrong points on certain overly explicit gear. With the Purifi amp, this music was perfectly enjoyable despite its many technical flaws. To my mind, this amp then struck an ideal very practical balance. It didn't turn 90% of my music-first library into rejects because its production values aren't up to purist par

Just something to think about, perhaps?

For EH another interesting piece haha 😕 Element 114
 
Or that difference may have been caused by level mismatch. Looks like some investigation is in order.

you keep going on about level matching.....What would be your protocol for proper ‘level matching’?

For example when I’m testing different changes I do it at the same input level of the same track played at the same volume setting then verified with a running average of the entire track (fr and dB level from lp.)

Some changes are going to equate to a different loudness perception but I don’t see that as controllable unless you eq everything flat after each change?

If this is the case then imo flat is not best.
 
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