John Curl's Blowtorch preamplifier part II

[Joshua_G]

Originally Posted by Soundminded

I'm saying he doesn't ever seem to see the forest for the trees.

While you didn't design anything that can be produced and sold on a commercial basis.

[brianco]

Originally Posted by Soundminded

No, I'm not implying anything. I'm saying he doesn't ever seem to see the forest for the trees. He usually focuses on just one tree and stays there. .................................................. .....................It gets to the point where the focus is on minutae so tiny you can't be sure of whether they are even real or not. Like intelligent chips.

There are many factors which affect the performance of a phonograph cartridge. To focus on the mass of the stylus tip to the exclusion of all of the other factors seems preposterous to me.

And perhaps that focus (on an end product) is why he has been successful when so many have not?

Having said that I do agree with your last thought far more than you will ever know!

[Groove-T]

Originally Posted by john curl

Groove T, have you ever MEASURED the power amp that you don't like to listen to? Look for 7th harmonic. Perhaps you won't find it, but it is probably something like that.
I now make 3 different power amps, one at less than $1000, another at less than $2500, and my best at $9,000. (big bucks, at least to me). They all get awards, IN THEIR PRICE RANGE. Why? What am I doing right? For the record, they are very similar in circuit topology, on paper.

My measure equipment is for service appliacations only, not enough resolution.
Maybe the 7th is the problem makes unconfortable to listen music.
But the big sonic difference is the bass. The small amp is vivid, alive and kicking with a tiny 150 Watt power supply, while the big one has 1200 W Power supply, can deliver 10 times more current, but the bass is still shy and uniform.
The importer modified with his negative output impedance trick he uses in his own brand *Rowen*, now i just hear the bass going somewaht lower, but the problem is not gone.

So i think the big one has a design problem, making very good tech specs. , but the sound is crap.

What you are doing right?
Good topology, careful with details, lots of experience, matched silicon devices, no unnecessary parts and circuits, short path, lesser solder joints (good lay out), good shielding and very good grounding toplogy, power supply quality,global feedback only when usefull and very important , the listening test. Did i forget something?

But of course, Mr. Pass, Mr Hansen and some others are also on the right track, imho.

The only negative aspect i found is: Your products are a pain in the *** when something fails (rarely the case), because matched silicon parts are a must, otherwise its up in smoke again.

[jan.didden]

Originally Posted by Groove-T

[snip]Technicallyspoken this is not possible, since the M3 datas ar far better by a magnitude, but with this machine i only want to turn the volume down while listening.
But with the small 326 there is music. Not perfect, but not fatiguing.

Explanation therefore ? I have none.

Bruno Putzeys once commented to me that "...amplifiers with the normal 20dB/decade [rising distortion] behaviour but whose distortion is not negligible at the end of the audio range have glassy mid-highs, a “superglue stereo image” and the illusion of spectacularly, unnaturally tight and impossibly controlled bass".
Could that be the reason why the 326 sounds so spectacular compared to the M3?

jan didden

[EUVL]

> "...amplifiers with the normal 20dB/decade [rising distortion] behaviour but whose distortion is not negligible at the end of the audio range have glassy mid-highs, a “superglue stereo image” and the illusion of spectacularly, unnaturally tight and impossibly controlled bass"

Does that mean good music ?


Patrick

[Telstar]

Originally Posted by EUVL

Does that mean good music ?
Patrick

IMO, not at all.

[Jakob2]

Normally elastic deformation occurs at the tip´s contact area and the area increases. Without this reversible deformation, damage would most likely occur as the pressure would exeed the possibilities of vinyl.

There is surprising litte information about the resulting damage during normal replay; in some notes from manufacturers using records for quality control purposes (measuring of frequency response) reported a variation of <1dB after several thousands of replays.

Loescher & Hirsch reported less record wear after usage of Lencoclean, which means that they couldn´t see any visible defects after 1500 wet replays compared to a dry replay (using microscopes of course).

A lot of this early work was published in the JAES (as a collection for example in two anthologies on disc manufacturing and replay) and will be accessible today via the AES e-library.

[SY]

And yet... all of the records that I played using Lencoclean (fortunately, not too many) turned horribly noisy. Several deep washings have not removed the noise. I haven't put them under microscopic analysis, but I do wonder if the rain slicked road caused repeated crashes into the guardrails.

[Soundminded]

Originally Posted by john curl

One tree at a time. Most here can't handle more. In fact, I have a hard time getting COMPLETE information on MC phono cartridges, but the links keep coming in, and learning is possible.

Perhaps in your next life you can tackle.....loudspeakers.

[Soundminded]

Originally Posted by Joshua_G

While you didn't design anything that can be produced and sold on a commercial basis.

That means I have no bias, no vested financial interest, nothing to sell and profit from personally. I sez 'em as I seez 'em.

Actually I have designed more things that were sold commercially than I can count. They just were not related to the audio industry. And BTW, many if not most of them carried far higher price tags than any stereo sound system, even very expensive ones. If my design approaches were in the same vein as much of what is called high end audio is designed, that is rejecting accepted mainstream engineering principles and making outrageous claims for performance that cannot be substantiated by demonstrated proof, I'd have had to go into a different line of work a long time ago.