John Curl's Blowtorch preamplifier part II

Status
Not open for further replies.
jkenny said:
Guys, you really should post this on the LP Vs CD thread How better is a Turntable compared to a CD?
It would also be good to add your Psychoacoustic insights into this thread sound processing by the human auditory system and it's relevance to audio


I just follow this thread for the most part. I just see this as JC's thread and it kind of encompasses all things audio ... it ebbs and flows and goes wherever JC and the moderators let it go, or something like that. I just go with flow and join in when I can.
 
Today, just for a few hours, I listened to my phono playback. Nothing new, just the same old Vendetta, CTC Blowtorch, and Parasound power amp driving some very old WATT 1's with a sub-woofer. It was glorious! I fell again in love with Julie London, rocked with the Grateful Dead from more than 40 years ago, and bounced with Dire Straits. There is nothing like a good vinyl record. It leaves EVEN my SACD's in the dust.
It is so much better than anything I have heard in the last 6 months, that it amazes me that others don't hear it as well. Well back to enjoying analog based music, the next best thing to live!
 
Administrator
Joined 2004
Paid Member
How were the Beatles remasters, I don't listen to them myself?

I have most of them and they pretty much live up to what was written about them by the team that did them. They do sound a bit louder, a bit more "modern" than the 1980s versions I have. And that's exactly what the remastering team claims. I don't find the difference to be huge, but overall there are improvements. On some songs - a large improvement. I prefer them over the 1980s CD versions, for sure.

I can't compare them to the vinyl versions, because mine are long gone. And the different pressings were known to vary, anyway.

BTW, the early albums are best in mono.
 
What sounds really good is the original White Album. By the way i do not think that you can improve the sound of an historic album. That is the authentic sound of that time. My wive for example prefers a back and white TV to a modern colour TV not to mention Plasma or LED.
Concerning noise Torsten is right that in praxis many people are superbly imune to noise.
Recently an Italien Tube Phonostage got rave reviews in two independent magazines from revievers i usually trust. One magaize measured it and it drove home a meager
-65dB / 1mV S/N. The MC stage made with 2 ECC83 in parallel without kathode resistors.
I do not like to know how much distortion that gives as a bonus. The stage costs 2500,-€ and the reviewer in the magazine that does not measure admitted that it was a bit noisy but it did not detract him from enyoying the sound. Later he "solved" the problem he got with his really low output voltage carts by inserting a 10.000,-€ silver transfomer from Japan. The Vendetta in it´s day must have being quite a shock and was and still is outstanding. We fight here for the last Ohm and other just build what they think is good enough.
 
I aggree with Joachim. I think we both were listening to the same Tube Phonoamp mentioned in the post before, at the Linestage shootout, .

It was a real salvation, when we switched to your phonostage, Joachim :D.

Comparing the review in one of the magazines with my personal listening impression strengthen my opinion about reviews:scratch:

Dear Sirs, please go on fighting for the last ohm, don't stop when you think " it is good enough"

Best regards

Sam
 
Member
Joined 2004
Paid Member
Rockport

Rockport? This is one of 4 remaining in the world, and the ONLY one with 45 and 78 speed. Two others are at Sony.
The rack in the bottom has the (inaudible) vacuum system.
Saw this at an audiophile friend in Bandung, Indonesia many years back.

jan

Not quite. That is one of the 4 big ones Andy built before the latest generation. The original requirement was for multiple continuously variable speeds and 1/2 speed operation for transfers of original material from the Columbia archive. It also had to run backwards for playing mothers. It can handle 16" or maybe its 18" disks with a vacuum hold down. There is a digital readout of the platter speed but especially for the older 78's you just have to listen and adjust to get the pitch right. It was a fun project. Last I heard the two at Sony were still running full shifts transferring the archives. The ultimate vinyl to digital transfer source.
 
AX tech editor
Joined 2002
Paid Member
The evil seventh

SY, seventh harmonic is avoided in many musical instruments, if possible. You should know this. Seventh harmonic is always out of tune. It is the worst example. Doesn't anyone here actually use Google to find out these things?
In musical reproduction, seventh harmonic appears to be the very worst harmonic to add to a hi fi system reproducing music. I think that this is what Joshua is trying to convey, Of course, seventh harmonic occurs in nature.
Of course, if you want to add a 'metallic sound' to your hi fi, this is the easiest way.

Steve, the problem with the 7th harmonic is that it sounds flat and shitey. Sure, it exists in the overtone structure of instruments but that's for flavour, timbre. You don't want to add more of it in your reproduction system. It sticks out.

See here:

Avoiding the 7th harmonic

It's been a problem for for Western and Eastern musical theorists for over two thousand years.

Hi John & Frank,

While looking for suitable steel-wire for my bicycle brakes ;), I stumbled by accident on the same article.
Indeed, it nicely explains why the 7th harmonic in particular sounds highly objectionable. To me it was a real eye-opener.
Here's another article that covers the same issue (regrettably in Dutch): Snaren en hun berekening - Prof.Dr.Godfried-Willem RAES
('Snaren en hun berekening' = 'the math of strings'. Real strings of course, not Feynman Diagrams :D)

Cheers,
E.
 
Disabled Account
Joined 2008
Hi John & Frank,

While looking for suitable steel-wire for my bicycle brakes ;), I stumbled by accident on the same article.
Indeed, it nicely explains why the 7th harmonic in particular sounds highly objectionable. To me it was a real eye-opener.
Here's another article that covers the same issue (regrettably in Dutch): Snaren en hun berekening - Prof.Dr.Godfried-Willem RAES
('Snaren en hun berekening' = 'the math of strings'. Real strings of course, not Feynman Diagrams :D)

Cheers,
E.

Hi Edmond
Not finished the bicycle yet, it's months since you told me that you were working on the bike. Have you replaced the front fork and got new (racing) brakes, what about the upgrading of the lighting system with LiFePO4 batteries?

BTW: you are right about the 7th. ;)

Cheers
Stein
 
Everybody through? It might be useful to talk about an audio amplifier topic.
However, it must be clear that some look for problems, and others tend to dismiss problems. Both camps are right to a certain degree, or NOTHING would work, but conclusions taken from one camp's position only, might make a design, either excessively difficult to make, perhaps impossible, or just something comparable that you can find at Radio Shack, and you should not waste your time, duplicating it.
I have found that keeping an 'open mind' yet trying to keep within the seemingly possible limits of engineering and physics, is the best bet.
I am not convinced that 'snake's blood' lowers the noise of a cassette tape, although John Atkinson and I saw a demo at a CES once.
But when it comes to Jack Bybee, I am convinced of his credibility, even if his products can be overemphasized by some, and totally rejected by others. I have known the guy for more than 15 years now, and I have actually taken his stuff apart, even if it cost the loss of the device. That is not really important, today, unless you want to attempt to duplicate it, as plenty of people have taken at least the larger devices apart and put photos of the insides up on the internet. I seriously doubt that taking apart one of the smaller devices would make any sense at all to the researcher, unless you had a complete physics lab. It is allegedly that sophisticated.
 
Last edited:
John,

Give it a rest. Obama has shown his pedigree, it is not going to change many minds.

Yes Jack Bybee makes a product based on his design ideas. Some folks who have tried them find they are worth the money, others don't.

Folks who haven't tried them and won't ever know they're bunk.

There is nothing but heat on the issue. So unless you are prepared to declare victory and move on, give it a rest!
 
Moving back to the original direction of this thread: I find that a number of subtle factors make 'all the difference' after the basic design needs are met.
This can be many things: Telescopes, cameras, TV's, hi fi reproduction, autos, etc, etc.
For example with an auto, the minimum might be something like a Renault Dauphine, or a Volkswagen Beetle. 4 wheels, highway speeds, 4 passengers, some sort of package carrying area. Everything from there is just 'improvements' whether for more power, comfort, style, etc. Can everyone go back to those examples of an automobile happily? If not, why not? What do you want an auto to do? Impress your friends, use up your excessive bank account, outrun the police? Do you see the absurdity of this? Of course, these reasons may be for some, but others of us see effortlessness, reliability, real comfort, and safety, especially as we get older, as even more important, and this costs money and years of engineering experience. Without an unlimited bank account, we can only have SOME of this, let me give some examples:
My older Porsche is fun to drive, reasonably responsive, far more than most autos on the road, fairly fast, (for the USA), pretty, and reasonably safe. It's downsides are no real back seats, kind of noisy (age, mostly), not comfortable over long distances, (my backside hurts after 50 mi), etc.
Jack Bybee's autos are: much faster, over 150 mph each, MUCH more comfortable, even in the back seat, effortless, safe, quiet, easy to drive, lots of features, etc. They also cost 10 times as much. Is it worth it?
It is the same with telescopes: Buy a cheap Tasco and note what you get. It will APPEAR attractive, to meet spec., somewhat useful and compact, BUT will you actually be happy with the results? Maybe, if you are a young person and know nothing better, but if you gain some experience in stargazing, you will find the compromises unsettling.
It can be said the same about many things.
Hi fi is but another commody, it has its range of quality.
Some people prefer a package system, just like their TV. Some like components, and to try different combinations of them. Some want to impress their friends. Yet others just want to listen to music without feeling the slight compromise that midfi systems usually give.
This is where my colleagues and I come in. We try to make reproduced sound as good as possible, and we may not always agree on the best solution or approach. This creates a healthy competition between us to make the best sounding components and we are quite serious about the differences.
Why this is questioned by some outside the audio fraternity as 'money wasters' or 'imagining the sonic differences' is beyond me. Like Ed Simon, if I can find a part, let's say a resistor, that is reliable, cost effective AND GOOD SOUNDING, then I will use it. It does not to be super cheap like some midfi designer HAVE to use to make their bottom line and remain competitive, but it does not have to be super expensive either. I quite happly lived and used a resistor that cost me $.05-.1 each, depending on quantity purchased, for decades. Alas, they don't make them anymore, so we have to find something else. Some people default to VERY EXPENSIVE resistors of $5-15 each. Is this a waste of money? Yes and no. The part is usually VERY GOOD, but the cost of the part(s) runs up the total cost of the design. IF and WHEN we can find something for, let's say $.5 that works just as well sonically, then we will go for it. It lowers the cost for us, and the final customer, but we don't like to take a chance with just anything, and this takes both subjective (listening) and objective (measurement) to determine which resistors we want to use for more serious designs. Is this so off the scale? Some here think so, but it is necessary for me, if I am going to be successful with my audio designs in future.
 
IF 'they are bunk' Ed Simon. You have to try them with good equipment and an open mind. Sometimes they actually 'screw up' the sound. I have heard it happen, myself, with Jack Bybee and the audio shop owner in a demo. But usually they work for the better.
Passive filters the likes of QP's can indeed screw up sound...recorded or live sound.
Applied correctly these can and usually do give great sonic benefits IMHO/IMHE.

Eric.
 
Today, just for a few hours, I listened to my phono playback. Nothing new, just the same old Vendetta, CTC Blowtorch, and Parasound power amp driving some very old WATT 1's with a sub-woofer. It was glorious! I fell again in love with Julie London, rocked with the Grateful Dead from more than 40 years ago, and bounced with Dire Straits. There is nothing like a good vinyl record. It leaves EVEN my SACD's in the dust.
It is so much better than anything I have heard in the last 6 months, that it amazes me that others don't hear it as well. Well back to enjoying analog based music, the next best thing to live!


I finally went to listen to my phono preamp, now that it is fully burned in from stem to stern... and I found I had managed to, ahem...'soften' one of the Rohm D786s transistors at the input.

Due to availability, it's a notable problem.

Any suggestions for a drop in or near drop in?
 
Status
Not open for further replies.