John Curl's Blowtorch preamplifier part II

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Try Water Lily ... purist - 2 mike recordings... all analog recording. Meeting by the River -- originally only on LP - now on CD/SACD. This is one I helped my friend sallie reynolds produce. Ultra clean and no compression, eq or anything except the Master musicianship. [Recorded inside a small church in santa barbara.]

Just bought 2 of the recommended CD by J.E. Thx. returning the favor -RNM

I've recommended Kavi Alexander's recordings numerous times, so what so so fatally wrong with 16/44.1?
 
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I've recommended Kavi Alexander's recordings numerous times, so what so so fatally wrong with 16/44.1?

I dont know.

I gave Kavi a host of electronics when he came to see me (TT/Arms, new ss pwr amps, tube AR preamp et al) and he asked me to design him a better mic preamp. last I heard from him he was in Hawaii and health not so great. he still asks for a better mic preamp. can you help him with a pair? How can i help you to help him? -RNM
 
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I dont know.

I gave Kavi a host of electronics when he came to see me (TT/Arms, new ss pwr amps, tube AR preamp et al) and he asked me to design him a better mic preamp. last I heard from him he was in Hawaii and health not so great. he still asks for a better mic preamp. can you help him with a pair? How can i help you to help him? -RNM

Last I heard he was all valve, custom mics with Pearl square diaphragms and all the signal path done by Tim de Paravicini. If he really needs help he should contact Martin Kantola of Nordic Sounds who also designs for Pearl.
 
One of the tests/interviews got me a job at LLNL over 4 decades ago. Later, I got a friend an interview at LLNL with MS in ME and a MS in CS and post grad work on an EE degree (I thought he was a professional student with super high IQ); he didnt get the job. he was a very theory oriented type of guy. Oh well. It takes all types. Almost. I ended up as a Senior EE technical coordinator for large physic programs/projects.... management. Havent had to design/engineer anything serious in 30+ years. I havent had a 9-5 job in 15 years. Just cruising and doing what I like, now. Glad i'm off the Merry -Go-'Round. So dont beat me up too badly here on old details and the small stuff. For me its about concepts and ideas. Or organizational issues but that's not needed here. :headshot:
I didn't intend to have you think I was laughing at you. I just thought how crazy it was that you aced the test then because of that they were saying "You did too well on the test".
 
Dear SY,

I was referencing the recording format, not the recording technique.

_-_-bear

What I meant is that I can't fault the CD version, as in if I can't hear the difference between this and 24/192 I'm deaf. They do much better with no compression than RR did on one of theirs, in trying to not clip someone pounding on a 10' Taiko drum much of the rest is inaudible (under ordinary "polite" listening).
 
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needs the Best -

Last I heard he was all valve, custom mics with Pearl square diaphragms and all the signal path done by Tim de Paravicini. If he really needs help he should contact Martin Kantola of Nordic Sounds who also designs for Pearl.

All true. But he doesnt care if it is ss mic preamp. Kavi has my prototype ss phono and said he liked it a lot. I dont know Martin Kantola... I think your design would be extreamly well recieved. Kavi doesnt like the mike preamp he has. I think he has been using another mic brand. Cole? I'll ask. -RNM
 
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Quote: Originally Posted by scott wurcer
Last I heard he was all valve, custom mics with Pearl square diaphragms and all the signal path done by Tim de Paravicini. If he really needs help he should contact Martin Kantola of Nordic Sounds who also designs for Pearl.

All true. But he doesnt care if it is ss mic preamp. Kavi has my prototype ss phono and said he liked it a lot. I dont know Martin Kantola... I think your design would be extreamly well recieved. Kavi doesnt like the mike preamp he has. I think he has been using another mic brand. Cole? I'll ask. -RNM

Water Lily Acoustics - [English]
In 2003, I sold off all my EAR equipment and purchased two Tascam DSD recorders, two Stellavox analog tape recorders (1/4 and 1/2 inch), a SoundDevices PCM recorder, Meitner DA/AD converters and Pearl ELM 8 and C mics. Mic preamps are by TrueSystems and Grace.
 
diyAudio Member RIP
Joined 2005
2SK2145, the ratings/specs are for devices in parallel operation or single devices?

Afaik not all jfets can be run "backwards"... most?

...then the question is the IDSS group 1/2 of the parallel IDSS or??

So, what is the application for a dual jfet with the sources tied together - or why not internally wire them in parallel and offer the device as a "single"?

_-_-

Most JFETs are close to symmetrical, with some manufacturers even calling them such. Of course DMOS is almost always associated with a body diode, for one, and is highly asymmetrical indeed.

There are four configurations at least that can use the committed "sources": everyone's typical differential amp; two (independent) grounded source stages; the follower with matched current load that EUVL mentioned; and the configuration where the one device is a current-source load for the lower device, forming an inverting amplifier. The latter works a whole lot better when one can cascode each of the two devices, something which the hardwired channel connections precludes :(

EDIT: And another, a simple cascode of the two FETs, although external bias needs to be provided for the upper gate.
 
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What's so fatally wrong with a bronze medal, losing in the playoffs (baseball, footzball), finishing a NASCAR race a few cars back from the winner, etc.?

Nothing, it works, just not as well...

_-_-bear
Disagee ... ;);) ... you just need to work harder to get it right; at the moment you have to pay silly money, or use something somewhat esoteric, or spend large amounts of time refining to get good results. Just grabbing something off the shelf and hooking it up is almost guaranteed to disappoint ...

CD reproduction is capable of truly amazing sound, it just don' come easy ...

Frank
 
Most JFETs are close to symmetrical, with some manufacturers even calling them such. Of course DMOS is almost always associated with a body diode, for one, and is highly asymmetrical indeed.

There are four configurations at least that can use the committed "sources": everyone's typical differential amp; two (independent) grounded source stages; the follower with matched current load that EUVL mentioned; and the configuration where the one device is a current-source load for the lower device, forming an inverting amplifier. The latter works a whole lot better when one can cascode each of the two devices, something which the hardwired channel connections precludes :(

EDIT: And another, a simple cascode of the two FETs, although external bias needs to be provided for the upper gate.


sorry this belonged on the Opamp thread, so I deleted it quickly and reposted it where it belongs... and thanks for the instant response, I think I had a brief power outage in my neural net... I knew this. heh.

_-_-bear <hides his head embarrassed>
 

As you see this business is fickle.

"Grace Design microphone preamplifiers are fully balanced, with
transformerless inputs and outputs. The input amplifiers are based on monolithic, low noise
instrumentation amplifiers."

A small diss of discrete design follows, they can't make up their minds.

And BTW Dick I plan to retire soon and to me that means NEVER having to commit to finishing anything ever to anyone.
 
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