New Repro cards!

Audiophile Bill

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Hi All - any news on developments here!?
 

Bruce B

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Follow up:

Listened to the original cards for a few weeks and heard some great things. There were tweaks I had suggested and I gave my feedback to Charlie and Jeff. Initially, I could live with the cards and be perfectly content.... but, could they even get better? Reluctantly, I sent them back and went back to using my outboard pre.

Fast forward to the later part of February and I get a call from Charlie. They had taken some of my suggestions and reworked the cards. Supposedly, they were sounding even better. I awaited with baited breath.

Picture below: Looks like a totally different card. "Next Gen" even!

I installed the cards over the weekend and run my basic MRL tapes through the cards. (MRL #21J203 and 241-673-512-100) using the FM heads I had installed at the time. Man, what a transformation! These could even flat eq 20kHz !! No problems with phase or anything, measured by FFT. They were looking promising, to say the least. Jeff had said that the cards were decoupled someway from the VU meter, so all measurements were taken from my Fluke 115. Jeff had also sent some XLR and RCA break-out cables to use as well, for those that don't have their heads wired directly out.

I had a couple audiophile friends come over that wanted to listen. They were mightily impressed. Just for sh*ts and giggles, I told one of my friends to change the switch in the back of the machine to go from the cards to my outboard pre (Doshi). We were listening to a sample tape that I had made for one of the Axpona shows.

I COULD NOT BLINDLY TELL WHEN THE $20K OUTBOARD PRE WAS PLAYING!! It's as simple as that. I know Charlie can give you more particulars, but from what I heard, I'm keeping them.

I changed the headblock to stock Studer heads, and the results were even better.......

I swear, I don't know how they did it. Charlie already had one of the best sounding outboard pre's out there. Now, he's taking some of that know how and putting it in a smaller (and less expensive) format. You owe it to yourself if you have a Studer A8xx series deck. They are working on record cards as we speak. Contact Charlie (stellavox) for any questions and availability. I can guarantee the results.....


66709635031__940472AB-52DD-4048-B8A4-22C5A56A242B.jpg
 
Last edited:

Audiophile Bill

Well-Known Member
Mar 23, 2015
4,293
4,093
675
Follow up:

Listened to the original cards for a few weeks and heard some great things. There were tweaks I had suggested and I gave my feedback to Charlie and Jeff. Initially, I could live with the cards and be perfectly content.... but, could they even get better? Reluctantly, I sent them back and went back to using my outboard pre.

Fast forward to the later part of February and I get a call from Charlie. They had taken some of my suggestions and reworked the cards. Supposedly, they were sounding even better. I awaited with baited breath.

Picture below: Looks like a totally different card. "Next Gen" even!

I installed the cards over the weekend and run my basic MRL tapes through the cards. (MRL #21J203 and 241-673-512-100) using the FM heads I had installed at the time. Man, what a transformation! These could even flat eq 20kHz !! No problems with phase or anything, measured by FFT. They were looking promising, to say the least. Jeff had said that the cards were decoupled someway from the VU meter, so all measurements were taken from my Fluke 115. Jeff had also sent some XLR and RCA break-out cables to use as well, for those that don't have their heads wired directly out.

I had a couple audiophile friends come over that wanted to listen. They were mightily impressed. Just for sh*ts and giggles, I told one of my friends to change the switch in the back of the machine to go from the cards to my outboard pre (Doshi). We were listening to a sample tape that I had made for one of the Axpona shows.

I COULD NOT BLINDLY TELL WHEN THE $20K OUTBOARD PRE WAS PLAYING!! It's as simple as that. I know Charlie can give you more particulars, but from what I heard, I'm keeping them.

I changed the headblock to stock Studer heads, and the results were even better.......

I swear, I don't know how they did it. Charlie already had one of the best sounding outboard pre's out there. Now, he's taking some of that know how and putting it in a smaller (and less expensive) format. You owe it to yourself if you have a Studer A8xx series deck. They are working on record cards as we speak. Contact Charlie (stellavox) for any questions and availability. I can guarantee the results.....


View attachment 90347

awesome - what is the pricing on these?
 

NextGen

Member
Mar 10, 2022
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Follow up:

Listened to the original cards for a few weeks and heard some great things. There were tweaks I had suggested and I gave my feedback to Charlie and Jeff. Initially, I could live with the cards and be perfectly content.... but, could they even get better? Reluctantly, I sent them back and went back to using my outboard pre.

Fast forward to the later part of February and I get a call from Charlie. They had taken some of my suggestions and reworked the cards. Supposedly, they were sounding even better. I awaited with baited breath.

Picture below: Looks like a totally different card. "Next Gen" even!

I installed the cards over the weekend and run my basic MRL tapes through the cards. (MRL #21J203 and 241-673-512-100) using the FM heads I had installed at the time. Man, what a transformation! These could even flat eq 20kHz !! No problems with phase or anything, measured by FFT. They were looking promising, to say the least. Jeff had said that the cards were decoupled someway from the VU meter, so all measurements were taken from my Fluke 115. Jeff had also sent some XLR and RCA break-out cables to use as well, for those that don't have their heads wired directly out.

I had a couple audiophile friends come over that wanted to listen. They were mightily impressed. Just for sh*ts and giggles, I told one of my friends to change the switch in the back of the machine to go from the cards to my outboard pre (Doshi). We were listening to a sample tape that I had made for one of the Axpona shows.

I COULD NOT BLINDLY TELL WHEN THE $20K OUTBOARD PRE WAS PLAYING!! It's as simple as that. I know Charlie can give you more particulars, but from what I heard, I'm keeping them.

I changed the headblock to stock Studer heads, and the results were even better.......

I swear, I don't know how they did it. Charlie already had one of the best sounding outboard pre's out there. Now, he's taking some of that know how and putting it in a smaller (and less expensive) format. You owe it to yourself if you have a Studer A8xx series deck. They are working on record cards as we speak. Contact Charlie (stellavox) for any questions and availability. I can guarantee the results.....


View attachment 90347

Bruce:

Charles and I thank you for the sterling kudos and recommendation regarding our first production NextGen A80 repro cards.

Yes, the repro board project has turned out exactly as we had hoped - as far as the features, specs and sound are concerned. Now to make them available.

The price is $3000 per set of repro cards. We have a few sets of boards available now with more in a month or so.

For ordering information, please contact Charles King (Stellavox) at Stellavox1@AOL.com or through this forum.

For full technical data or inquiries please contact Jeff Polan (NextGen) at jpolan@yahoo.com or through this forum.

Best Regards
Jeff and Charles
 
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NextGen

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Charles and I are thinking about producing a NextGen Repro Card for the A810/A820 - very similar in design (discrete all direct coupled Class A with outstanding low noise, distortion, and temporal characteristics ) to our new A80 repro card that Bruce Brown of Puget Sound Studios reviewed very favorably in comparison with the Doshi recently in this thread.

Tentatively, the new A810/820 repro card would provide

(1) front panel direct balanced- and single-ended outputs accessed by a breakout cable plugged into the front-panel of the card;
(2) switchable EQ (NAB/CCIR/AES and other) but without support for Sel-Sync (repro through the record card)- i.e. repro only;
(3) possible elimination the Multiplying DACS for conventional trimpots; if so this would mean EQ adjustment by the trimpots rather than the microprocessor and software.
(4) The front panel outputs would bypass in their entirety mono/stereo switching and line output cards, but the machine's existing repro line outputs and metering would remain fully functional.

Even considering the age of the design, there exist a number of very serious weaknesses in the A810/A820 repro audio design (including multiple stages of NE5532 op amps in the signal path, the multiplying DACs and additional NE5532 buffers used for setting EQ, Treble, Bass, and Level adjustments, and we feel very confident that the new board with direct outputs bypassing as well the opamp Line Card circuits will be a listening revelation.

We are eliciting interest for such a product.

One design element that is still up in the air is whether a discrete preamp section will be moved as well to the repro card (unlike today with 2-channel NE5532 opamp preamp in the head block, which would then be simply bypassed), or whether a separate new high performance discrete class A preamp board would be installed replacing the existing one in the head block (actually, it is not all that clear that just bypassing the existing preamp board and including the preamp on the new repro card - as it is on our new A80 repro card- would give up any hum and noise performance as experience on other decks indicates that noise floor is set directly by repro head pickup itself - not the cabling from the repro head to preamp if balanced or pseudo-balanced).

The small form factor of A810/820 audio cards - as well as the in- head preamp - complicates the decision as well unless we want to adopt surface mount assembly - but which entails high costs for small volumes; a separate new discrete preamp board - if we go that route - would fairly certainly require surface mount assembly as well - but removing it to the head block might just allow us to use through hole components on the new repro card. So it is important to get a sense of the actual interest/demand for such a planned product.

We have set a tentative target of between $3K and $4K dollars per stereo set. Again, this is designed to be a purist solution that will carry the A810 and A820 into an entirely new category of replay performance.

If there exists sufficient interest in the audiophile/professional community we would likely proceed with the development, so please let us know.

Regards,
Jeff Polan and Charles King.
 

microstrip

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Did you consider the possibility of building an in- head preamp for the A80's , as ATAE had done in their models?
 

NextGen

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To get a solid idea of the specs we would expect for a new A810/A820 repro card, please refer to the following specs for our NextGen A80 repro card that Bruce Brown just reviewed:

NextGen Studer A80 Repro Card - Key Features & Characteristics:​

Finally: a "Plug & Play" Studer A80 Repro Card that transforms the legendary Studer A80 into the
world' finest Magnetic Tape Music Reproducer.

IMG_1680.jpg

Key Design Elements & Features:

  • All direct-coupled discrete transistor class A circuitry, Repro head input to Front Panel single-ended (RCA) output for the purest possible sound;

  • Two precision balanced transformerless (TI DRV134) outputs:

  • Front Panel Repro-only output, entirely separate from the regular A80 un-buffered VU meters/Bridge/Balanced output for lowest distortion and best possible balanced sound; and

  • "Standard" A80 output for the legacy VU Meter Bridge, Input- or Repro- selection, Record and Playback volume controls, using existing A80 XLR connectors;

  • No capacitors anywhere in the signal path except for a single high quality precision polypropylene capacitor (Dielectric Absorption <0.05%) to set LF and HF EQ turnover characteristics (NAB/CCIR/AES/OTHR), a single similar polypropylene capacitor to set Repro Head-/Wavelength- Model correction at the Low Speed, and a single similar polypropylene capacitor used in the DC servo; time-smear effects all but eliminated;

  • NO shelving or parametric Bass and Treble corrections (i.e. "Tone Controls") employed for EQ adjustment and calibration, realizing near-ideal time domain response;

  • Available in 15/30 ips and 7.5/15 ips models, each with Four Switch-Selectable wavelength-optimized Equalizations built-in:

  • 15/30 ips NextGen A80 Repro Card:

    • 15 ips: NAB, CCIR,

    • 30 ips: AES,

    • OTHR: CCIR (30ips), or 10uS (15 or 30 ips), or FLAT (15 & 30 ips)

  • 7.5/15 ips NextGen Repro Card:

    • 7.5 ips: NAB,

    • 15 ips: NAB, CCIR, AES,

    • OTHR: 10uS (15ips), or FLAT (7.5 & 15 ips)

  • "OTHR" offers 15 ips AES, 10uS turnover, or speed independent FLAT (i.e. UNEQUALIZED) characteristics as standard offerings; please contact us if you have other EQ requirements.

  • HS Gain, LF- and HF- EQ calibration adjustments for High Speed (30 or 15ips), with modeled Bass and Treble corrections applied for Low Speed (15 or 7.5ips) linked to the High Speed calibration settings, and LS Gain

  • Specifications[1]:

  • Exceptionally low-noise:

    • 2.5nV/?Hz EIN with 200 ohm source, 20Hz-20Khz; 83dB wideband SNR and 95dB A-wtd SNR re 355nW/m 0.5Vrms single-ended or 1.0Vrms balanced output
    • 80 dB SNR A-wtd re 355 nW/m in the deck, tape stopped and capstan running (15 ips NAB), better than -69 dB A-wtd re 355nW/m playing virgin unrecorded blank tape at 15 ips NAB, -71dB at CCIR, -73 dB at AES (Studer A80 butterfly stereo repro head, 1/4" tape);
    • repro card A-wtd noise floor is 15 dB below deck A-wtd noise floor, and 22-26 dB A-wtd below virgin tape for 1/4" tape (about 1.3 dB less for 1/2 track 1/4" tape)
    • repro card A-wtd noise floor is about 12 dB below deck A-wtd noise floor, and 19-23 dB A-wtd below virgin tape for 1/2 track 1/2" tape at same output operating level
  • Accurate equalization conformance, extended frequency response, and superior time domain performance, optimized for the Studer-supplied A80 Butterfly or 1/2 track heads; when set at recommended output operating levels relative to tape fluxivity[2]:

    • 30 ips AES: typically achieves equal or better than ± 0.75dB 125Hz - 20 Khz, and less than 1.5 dB error at 32 Hz and 63 Hz, according to MRL 250nW/m (full-track) calibration tape, applying standard (McKnight published) low frequency fringing corrections[3]; -1 dB at 25Khz record/repro response;
    • 15 ips NAB, CCIR (also 15 ips AES & 10us with calculated corrections): typically achieve equal or better than ± 0.75dB 63Hz - 20 Khz at 15ips, and less than 1.5 dB error at 32 Hz according to MRL 250nW/m full track calibration tapes applying standard (McKnight published) low frequency fringing corrections3; -3 dB at 25Khz record/repro response;
    • 7.5 ips NAB: typically achieves equal or better than ±1 dB 50Hz - 16 Khz according to MRL 250nW/m fringing compensated NAB full track calibration tape[3].
  • Exceptionally low THD and IMD distortion:

    • at least 30 dB (30x) improved over stock Studer A80 Repro card 20Hz - 20 Khz at all operating levels;
    • THD at 1.0Vrms single-ended output/2.0Vrms balanced output NAB:
    • 1Khz better than 0.001% (100 dB down), typical -106 dB (0.0005%) single-ended;
    • 32Hz better than 0.01%
    • 10Khz better than 0.01%
    • 10+11 Khz IMD 1:1 at -3 dB re 1.0Vrms sum power NAB: better than 0.01%, -102 dB re sum 2nd IM product, -112 dB re sum 3rd IM products
  • Outstanding headroom:

    • Equal or better than 0.01% (-80 dB) THD 20Hz - 20Khz at output level corresponding to +19 dB above 355nW/m (4.5Vrms single-ended/9Vrms Balanced outputs), +13 dB above 355nW/m (Balanced to single-ended output); rated maximum output is 7Vrms single-ended or 14Vrms Balanced (equivalent to +22 dB above recommended 355nW/m output at -6dBv rms/-3.9dBm)
  • Improved Ch-Ch crosstalk better than -70 dB 300Hz - 3Khz (typically -75 dB at 1 Khz) and -55 dB 100Hz - 8Khz (Butterfly Stereo Record and Repro Heads) using the built-in XTLK canceller

  • Front-panel single-ended RCA output (from 4-pin mini-XLR breakout cable) for highest possible performance in short single-ended cabling conditions where hum and noise pickup is not a problem.

  • Front-Panel balanced transformerless output (from 4-pin mini-XLR breakout cable) entirely separate and independent of the standard Studer balanced output and VU meters/Bridge for exceptional balanced output performance.



[1] All in-deck specifications based on properly-operating/well-regulating Audio Stabilizer Card.
[2] See following "Recommended Settings"
[3] Please see the Note following about calibrating/adjusting LF Equalization, below
 

AEAaudio

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Mar 21, 2022
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I would be very interested at that price...
 

NextGen

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Did you consider the possibility of building an in- head preamp for the A80's , as ATAE had done in their models?
Yes. What we found after extensive measurements on the A80 is that repro cable pickup Itself contributes no meaningful contribution to the actual noise floor with well-designed on-card preamplifier (including RFI suppression); effectively all the “noise” pickup is directly thru the repro head gaps themselves, captan motor dominant even with the double-shielded 30 ips capstan motor. In addition, the repro gap / channel closest the baseplate (and capstan motor) has a bit higher A-wtd noise (About +1dB).

With our new A80 Repro card the A-wtd noise floor is within 1 dB with capstan and reel motors running and tape moving, and all motors stopped, on each chan, and Represents approximately 80 dB SNR A-wtd below 350nW/m fluxivity in the deck.

The NE5532a opamp used in the Studer A810/820 headblock is spec’red at 5nv/root Hz at 1 kHz, or +8.5 dB higher than our A80 repro card Preamp, and +16 dB higher at 30 Hz than our press; in addition the NE5532a has 1000x higher bias current flowing through the head at 200nA typical, leading to some head magnetization and additional nonlinear distortion.

Consequently, with the A80 there is no benefit to be had with a headblock preamp stage over the one built on our NextGen A80 Card.

In the case A810/A820 the electrical situation is exactly the same. But the smaller form factor of the repro card presents difficulty packaging all the discrete circuitry unless surface Mount is used so we consider placing the preamp stage back in the headblock.

thx for your inquiry.
Jeff
 

microstrip

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Yes. What we found after extensive measurements on the A80 is that repro cable pickup Itself contributes no meaningful contribution to the actual noise floor with well-designed on-card preamplifier (including RFI suppression); effectively all the “noise” pickup is directly thru the repro head gaps themselves, captan motor dominant even with the double-shielded 30 ips capstan motor. In addition, the repro gap / channel closest the baseplate (and capstan motor) has a bit higher A-wtd noise (About +1dB).

With our new A80 Repro card the A-wtd noise floor is within 1 dB with capstan and reel motors running and tape moving, and all motors stopped, on each chan, and Represents approximately 80 dB SNR A-wtd below 350nW/m fluxivity in the deck.

The NE5532a opamp used in the Studer A810/820 headblock is spec’red at 5nv/root Hz at 1 kHz, or +8.5 dB higher than our A80 repro card Preamp, and +16 dB higher at 30 Hz than our press; in addition the NE5532a has 1000x higher bias current flowing through the head at 200nA typical, leading to some head magnetization and additional nonlinear distortion.

Consequently, with the A80 there is no benefit to be had with a headblock preamp stage over the one built on our NextGen A80 Card.

In the case A810/A820 the electrical situation is exactly the same. But the smaller form factor of the repro card presents difficulty packaging all the discrete circuitry unless surface Mount is used so we consider placing the preamp stage back in the headblock.

thx for your inquiry.
Jeff

Thanks for your extensive and extremely well documented answer. Can you ship your cards from an EC country?
 

NextGen

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Thanks for your extensive and extremely well documented answer. Can you ship your cards from an EC country?
Sorry to say not at this time, as our NextGen A80 card is new and we do not yet have a distributor in the EC.
We also offer a 1 year warranty regardless of your location.
Regards
Jeff
 

NextGen

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As far as our proposed NextGen A810/A820 repro Card replacement, let me also add the following to illustrate the potential improvement in sound and accuracy versus the current A810/A820 repro electronics for those not too technical:

Studer A810/A820 repro card (1.820.710.82) and headblock preamp (1.810.712.00) :
Repro audio signal passes through : 11 Aluminum Electrolytic Capacitors, numerous additional mylar/PTP and ceramic caps - all of which display rather horrible Dielectric Absorption/memory effect leading to significant time smear, 8 NE5532 opamp sections, and 2 DMOS jfet switches (poorly engineered in that even with all these opamp sections they are NOT working into virtual grounds for lowest distortion);

NextGen A80 repro card replacement (and proposed A810/A820 design):
Repro audio signal passes through NO electrolytic Capacitors, and apart from only 2 precision Polypropylene (DA<0.05%) caps (one to set EQ turnover, and one for DC servo), is DC-coupled in its entirety; there are also just 2 precision Polypropylene shunt capacitors (repro head load, and wavelength model for Low Speed EQ correction).

The front-panel single-ended output comes directly off the EQ stage, is unbuffered and entirely discrete head input to RCA output for purist possible sound; the front-panel balanced output is transformerless and comes off a TI DRV134 balanced driver (the entirely separate regular A80 balanced output also comes off a TI DRV134 driver, but suffers audio degradation by the machines un-buffered VU meters).

In my opinion, while the A80 and A820 transports were (and remain) superb precision-guided transports and rightly admired with excellently low FM and AM flutter sidebands, the A810/A820 audio electronics look to have been designed by digital engineers rather than audio engineering specialists, or were severely pressured to put digital features and convenience ahead of ultimate audio quality. What can be achieved by upgrading the audio electronics in these machines is very evident both in measurement and listening.


Rgds
jeff
 

five

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Dec 29, 2018
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Dallas, TX
I’m likely interested in 1 or 2 sets of the A820 cards. From my perspective, the closer they can be to a direct plug-in replacement, the better.

The convenience of having multiple EQs and speeds easily available is a really nice feature which ideally would be maintained. However I presume that the digital select logic and multiplying DACs take up more board space than multiple sets of trimpots and a selector switch which is probably why you are thinking of going that direction. Plus doubtless it simplifies things. So if that capability has to be dropped, in favor of a selector switch on the card, it probably wouldn’t be a deal killer for me.

My strong preference would be to not simply bypass the headblock preamp. And if a replacement is created (likely required to get the quality you are after), it would be very nice if it was compatible with the current one so that headblocks are interchangeable between machines with the existing and your new reproduce amplifiers.

I presume it doesn’t make sense to also create replacement Line Amplifier cards too? While that would give you twice as much board space to work with, it probably also means that there’d be lots of additional stuff you’d have to interface with. I’m guessing that trade off doesn’t make sense?
 

NextGen

Member
Mar 10, 2022
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I’m likely interested in 1 or 2 sets of the A820 cards. From my perspective, the closer they can be to a direct plug-in replacement, the better.

The convenience of having multiple EQs and speeds easily available is a really nice feature which ideally would be maintained. However I presume that the digital select logic and multiplying DACs take up more board space than multiple sets of trimpots and a selector switch which is probably why you are thinking of going that direction. Plus doubtless it simplifies things. So if that capability has to be dropped, in favor of a selector switch on the card, it probably wouldn’t be a deal killer for me.

My strong preference would be to not simply bypass the headblock preamp. And if a replacement is created (likely required to get the quality you are after), it would be very nice if it was compatible with the current one so that headblocks are interchangeable between machines with the existing and your new reproduce amplifiers.

I presume it doesn’t make sense to also create replacement Line Amplifier cards too? While that would give you twice as much board space to work with, it probably also means that there’d be lots of additional stuff you’d have to interface with. I’m guessing that trade off doesn’t make sense?
Thanks very much for your interest and valuable feedback; you are absolutely correct regarding footprint taken up by the M-DACS and the associated NE5532A I/V buffer(s) on each; we will use the identical small multi-turn Bourns trimpots as used on our NextGen A80 repro card that Bruce Brown reviewed most favorably.

As far as the original headblock preamp is concerned, it is simply not a great design - even for its era - and makes numerous serious compromises, among them: the rather high noise and Ib/DC head current, mediocre BW/slew/rate/settling time and linearity (distortion) and it even compromises XTLK compensation by sharing just a single adjustment pot for both L-R and R-> L setting where there should be two (even the older A80 had individual L-R and R-L XTLK adjustments). All the sound you hear from the machine in repro starts with this headblock preamp, yet I would think the entire 2-ch headblock preamp could not have cost Studer more than $20-25 in materials, assembly, and test, this for a machine I believe cost more than $10K when released, and A820 machine up around $20K (someone please correct me if my recollection is wrong on these prices). So the headamp will either have to be bypassed or be replaced entirely.

As to the Line cards, certainly they also do not stand up particularly well, and I suppose if we designed a replacement Line Card we could pick up quite a bit of space on these cards as well as improve greatly performance - but how much could actually be utilized to extend the footprint of a repro card function is not entirely clear given existing backplane connectivity as you say, as well as software implications, and at the very least still require two new cards. If workable it would perhaps eliminate a new headblock preamp and require bypass the existing preamp.

Like you, I certainly prefer a new headblock 2-ch preamp IF it would allow us to use through-hole manufacture of the associated Repro Card; if it would not, and we need surface mount manufacture for the Repro Card with the built-in preamp, it may make more (economic) sense to bypass the Headblock preamp, but only once we verify (as I expect) both approaches will have identical noise floor and RFI immunity.

In our current NextGen A80 class A preamplifier (or Equalizer) stage we have 11 discrete transistors (jFets and bipolars), about 20 precision resistors and film caps, 2 trimpots (DC balance and XTLK) etc. per channel. The current Studer headblock preamp has about 2 square inches footprint (and 1.5 cubic inches total) available for the two preamp channels, so we are looking at a new headblock preamp design with two stacked surface mount cards, to replace the current Studer 2-ch head block preamp design as the most likely solution, and one that is as compromise free of performance limitations as can be built today, at any price.

The Repro Card will contain the Equalizer, Rotary switch for EQ selection, Front-panel Breakout connector for the XLR and direct single-ended outputs, trimpot access, mute circuit, and a small toggle switch for Hi-Lo speed select (adjusts the head gap- and wavelength modeling- for the LS).

We are not at this time planning to support the Sync function (repro from the Rec Head), because of the additional space demands om the Repro Card..

But please NOTE that this new headblock preamp can simultaneously drive a second set of entirely outboard electronics (like our A80 NextGen cards less the redundant preamplifier stage) so there exists the option of retaining the original Studer Repro card with its Sync function and using the superior outboard electronics for the best repro performance. This adds another factor to consider.

Einstein famously advised "Things should be made as simple as possible, but no simpler."

I expect we will know quite soon which configuration
(1) new surface mount headblock preamp and through-hole Record Card; headblock returned by most users to us for installation and test;
or
(2) User-bypassed headblock preamp and new surface mount Record Card with inbuilt preamp;

makes the most sense from both an economic-, and and user- preference point of view, assuming both deliver identical audio performance (which will be verified). For now we still carry forward both approaches.

Users: please chime in if you have a strong preference.

Regards
Jeff
 

five

Well-Known Member
Dec 29, 2018
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Dallas, TX
I shall look forward to seeing what you come up with. Let me know if there’s anything I can do to help.
 

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