John Curl's Blowtorch preamplifier part II

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In fact IMO its even more enjoyable when you know that it really shouldn't work as well as it does.
Is that is a product of understated mid 20th Century concept and design, or of empirical chance I wonder? I favour the former, there were some clever bods with a free reign and high standards. A Decca SXL record in the 1960s cost a working week's wage..... that might be a couple of hundred quid for a CD today (!) it had to be excellent, work well, and last.

What makes the investment in playback aggro worthwhile for me is that the original mastering, ie the intended sound presentation as it was conceived to be heard, is only present in those grooves. And that is always a bit special really. Mastering taste and presentation choice has changed significantly over the decades, and is shaped by the physical media. Bona fide makes it worthwhile, IMO.
 
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Confession: I have started collecting the Decca remaster box sets on CD. The analogue years set is 54 CDs for £83. Getting mint copies of the originals if you don't have them will run a lot higher than that. Would be interesting comparing and contrasting with someone who does tho! sadly they keep releasing new ones!

EDIT: dangnabbit didn't realise they did 2 box sets of the analogue years. I have 68-80 but not 54-69, which is out of print but only £42 as a flac download. Churlish not to...
 
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For those of you who are into jazz - check this young pianist out, if you have a chance - Beka Gochiashvili
I saw him with Stanley Clarke in a trio in what must have been one of their early gigs a few years back now. They make great music.

But if prodigy is yer bag, not much beats the Julliard free lunchtime recitals IMO..........

.....or at the other end of the spectrum I saw this 7 year old kid, Jonah Rocks, busking to a backing track (with his family), and from a few blocks away thought 'blimey he's a good drummer' enough to take a diversion and have a listen:

https://www.youtube.com/watch?v=_LkLssAvA38

That track he's playing a double kick, but check out his other youtube stuff for touch and finesse on the hi-hat.........
 
EDIT: dangnabbit didn't realise they did 2 box sets of the analogue years. I have 68-80 but not 54-69, which is out of print but only £42 as a flac download. Churlish not to...
Yes, they are great recordings of great performances, and no matter what media that is bound to shine through. It was the 50s/60s Decca stuff that got me back in to vinyl, and I have a fair SXL/LXT collection - the content should be great no matter what media.
 
Enjoying vinyl is not a sin.
Of course (And I still have hundreds of great LPs and a strait arm turntable).
Just, I don't see where is the interest to talk so much about-it, to try to design improved preamps for MC cartridges etc...
It is an obsolete technology of the last century which reached its highs in the 70s and which we can not really expect more than it offered in its time.
A beautiful moment technology, which now has no other interest than the pleasures related to "vintage" or 'collection'.
More than this, when some try to make believe that digital is not 'musical' (when I'm not able to make any difference between pre/post good digital recording), this may be a barrier to advances in current technology, which has not reached its peaks and is, yet, thousand times better, even on an economical point of view.
 
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well actually we are mainly talking MM, which in general doesn't seem to have had as good a deal as MC preeamp wise.

In my admittedly limited research i can only find the Shure V15V that comes close to a flat FR when loaded to factory specs. There must be others but most are all over the shop. No wonder a generation of us abandoned a potentially superior technology for the allure of hewn by virgins MCs. I know I did.
 
Well don't just stand there man, bend it before someone turns you in........
I don't need to do-it myself, it's a servoed motor that take care to keep the arm tangential.
Anyway, i was always amused to see all those arms in S or any other strange figures: the strait line is supposed to be the shortest path from a point (pivot) to an other (diamond).
 
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In my admittedly limited research i can only find the Shure V15V that comes close to a flat FR when loaded to factory specs.
Indeed, and not just MM, MC too. There's not much to split them. Check out dozens of carts MM/MC measured under similar test conditions for comparison. Look for frequency response 500-20kHZ lateral -8dB for each cart and compare, it is indeed all over the shop.

Miller Audio Research

You have to register, which is automated and free. It's a good site, and most current carts are reviewed including all popular MC and MM. You have to sift through by year. 2013 has quite a good mixture.

Any cart can be levelled in f response by selection of loading, though perhaps exotic sometimes. You need to look out for variation with level too. The best I've seen is the combination I use which is an OM40 into one my own transimpedance preamps, which happens to be MM (well MI/MM strictly).
 
Why not just use a JFET CCS instead of R1 ?

If you use 2SK2145 or 2SK209 (all Idss grades available at Mouser), and replace the trimmer with 2 fixed resistors,
you have good thermal tracking (stable DC) and can make this real small, most likely within 12x12mm for 2 channels.

OK, maybe not with 470uF caps ...... But Nichicon SW has 100µF 6.3V at D5 x L7.


Patrick

That all makes sense, just grabbed some stuff and soldered it together, the trimmer was to seek the 2nd harmonic null point. You can put only the JFET's and the input matching load at one end and the rest at the other. Ground and the two ends of the battery and two single ended outputs, the impedance level at the sources is pretty low should help minimize noise pickup.
 
The orient express still sells out when it runs.

Does that nostalgic train still run in Scotland? Can't remember the name, they would stop a a station and the chef would go out and bargain with folks for the ingredients for the nights meal some wild caught or foraged. It looked like three star dining on wheels. AMTRAK food is a different experience.
 
not a very user friendly registration and very confusing to those of us who are completely literal.
Yes IIRC it tries to open a form to send as an email, which looks a bit scary in explorer and which trips security alarms. What you can do instead is just copy the email address and title, then send an ordinary email to that address with the correct title, and just include your name and email address in the body text of the email. Then a registration username and password is returned by email pdq IIRC.

Did you get in anyway, bill ? It's worth the aggro IMO.
 
nope, tried and no email came back. does it expect just name and email or name=$NAME format?
From memory, the title of the email has to exact. The body of the email should just contain just one line with your text name and email address, no formatting. Then send it to the email address that it wants to send the form to. I thinks that should work.....

Nothing worthwhile in this life is easy.....:rolleyes:
 
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