John Curl's Blowtorch preamplifier part II

[jacco vermeulen]

Originally Posted by 1audio

A pretender to Ultra high end.

Vikings are sold here in the more luxurious DIY home centers.
Lacanche and Molteni are more my thing. (i've cooked on a classic Aga, tricky stuff)

My point is that a reel to reel still is mundane, and Tascam was the last of a dying race, relatively cheap too in the final years.
(as is Viking, Sub Zero fridges are cool though)

[john curl]

Sorry, those are 30+ year old schematics, and all I have left, after the firestorm.

[john curl]

Lousy analog tape electronics and tape is forgettable. Quality analog tape electronics AND fortunate tape recordings, from the past, are unforgettable.

[john curl]

I have a whole bunch of reel-to-reel recorders, mostly modified better than stock, in storage. I might just get 1 or 2 out, and listen, today, for myself.

[elektroj]

I should start with disclaimer first: I am neither against DIGITAL nor ANALOG. They both happily coexist in my world

Originally Posted by john curl

Not really, when you compare the ANALOG ELECTRONICS after a typical DA converter. I just got a 192K-24 bit 2 ch sound card, and it is only marginally hi end quality.
Analog tape playback does NOT have the DIGITAL problems that many audiophiles (like me) hear, and are NEVER satisfied just with digital.
Others, like Scott, seem to not notice digital problems, anymore, lucky him! '-)

IMHO, high quality digital record/playback has gotten very very good these days. One just have to select the right equipment.
John, why don't you design post DA stage using "Vendetta's" style topology and be done with it? Transconductance amp, that is capable of withstanding fast transients is what is needed there.
Saying that one has 192k-24 capable equipment is about as informative as saying that he/she has amplifier with 0.0001% THD. Besides, sound cards are never high end. Think of environment they're operating.
Yes, digital has its problems, but are people, those that are raving about analog tape recording/playback, aware of problems and unavoidable errors it has? Where should I start?

1. Head bumps due head geometry.
2. Gap loss.
3. Spacing loss.
4. Azimuth errors.
5. Cable C and head L resonance.
6. Phase errors due to non complimentary pre-/deemphasis.
7. Freq. response errors inevitably created by differences between various calibration tapes.
8. Tape noise. Yes, noise
9. HF loss by tape some time after recording.
9. Post or pre-echo due to tape storage.
10. Flutter.
11. Scrape flutter.
12. Speed stability.
13. Tape moving up and down due to imperfect tape path.
14. Generation loss (when dealing with copies of "master tapes").

Did I miss anything?

[Pano]

Originally Posted by john curl

Not really, when you compare the ANALOG ELECTRONICS after a typical DA converter. I just got a 192K-24 bit 2 ch sound card, and it is only marginally hi end quality.

Kinda old news, but legit. Have a look around some other sections of this site and you'll see a lot of folks replacing the analog section as it's a well known weak spot. I first saw it done in the 80s with a GoldStar (now LG) CD player modified for tube output. DAC hot-rodding is a long tradition.

Speaking of the 80s, we were still using 30ips then on our Studer and other tape machines. 15ips was for home recording sissies.

[a.wayne]

Originally Posted by john curl

Lousy analog tape electronics and tape is forgettable. Quality analog tape electronics AND fortunate tape recordings, from the past, are unforgettable.

True dat ...

Originally Posted by john curl

I have a whole bunch of reel-to-reel recorders, mostly modified better than stock, in storage. I might just get 1 or 2 out, and listen, today, for myself.

You should , yanked the Teac out a couple years ago , with good tapes the sound is good and I'm sure with refurbished caps and PSU it would be a lot better . While not as good as my digital , it impressed all who have heard it sing ...

[Chris Hornbeck]

Originally Posted by elektroj

Did I miss anything?

Sticky shed. The worst problem of mag tape is that it's not archival, even over a single human lifetime. Plastics rot, unfortunately.

Thanks,
Chris

[elektroj]

What would a diehard audiophile say seeing those curves?

Response Curves of Analog Recorders

[a.wayne]

Measurements dont matter ......