RCA inputs on ATAE LNP-3 tape preamp?

[dminches]

Mike, do you use an external tape pre or the Studer electronics?

 

[Mike Lavigne]

Mike, do you use an external tape pre or the Studer electronics?

mostly I use the external King Cello tape repro output electronics from direct out of heads.

I also use the stock Studer electronics sometimes.

I have Trafoless (Transformerless) cards on my 1/2" A-820 which do sound better than the stock Studer electronics. I could switch them to the 1/4" if I wanted to.

 

[astrotoy]

mostly I use the external King Cello tape repro output electronics from direct out of heads.

I also use the stock Studer electronics sometimes.

I have Trafoless (Transformerless) cards on my 1/2" A-820 which do sound better than the stock Studer electronics. I could switch them to the 1/4" if I wanted to.

Thanks, Mike. Did you get your second A820 so you could have one machine to play 1/4" and one for 1/2"? I thought changing heads was pretty quick on the Studers. I got my second ATR-102 to be able to do dubs. Only one has an output for my external prepro. So I use it for both 1/2" and 1/4" tapes.

Larry

 

[Mike Lavigne]

Thanks, Mike. Did you get your second A820 so you could have one machine to play 1/4" and one for 1/2"? I thought changing heads was pretty quick on the Studers. I got my second ATR-102 to be able to do dubs. Only one has an output for my external prepro. So I use it for both 1/2" and 1/4" tapes.

Larry

Larry,

yes, I wanted another top level machine with 1/2", as well as an easy way to dub tapes with 2 top level transports. and both my A820's have switchable direct head outputs for the King Cello. and I can use the King Cello to improve my dubs over the stock electronics, but only on the output. the input is still stock.

I'm told that switching from 1/4" to 1/2" head blocks and guides (which I've done and only takes 5 minutes) is not ideal due to micro adjustments needed for optimal tape tension for ideal performance. but this is not anything I know for myself, only told to me by much more technically expert people (I cannot defend that perspective). not sure whether that is the same for the ATR-102.

I think one needs some pretty good tools and knowledge to adjust tape tension.

 

[astrotoy]

Larry,

yes, I wanted another top level machine with 1/2", as well as an easy way to dub tapes with 2 top level transports. and both my A820's have switchable direct head outputs for the King Cello. and I can use the King Cello to improve my dubs over the stock electronics, but only on the output. the input is still stock.

I'm told that switching from 1/4" to 1/2" head blocks and guides (which I've done and only takes 5 minutes) is not ideal due to micro adjustments needed for optimal tape tension for ideal performance. but this is not anything I know for myself, only told to me by much more technically expert people (I cannot defend that perspective). not sure whether that is the same for the ATR-102.

I think one needs some pretty good tools and knowledge to adjust tape tension.

Thanks, Mike. The 102 may be easier to change over, since there is no tape tension to adjust - just replacing the two tape guides and the head block. Have you tried the Doshi (I have the 3.0 which Nick is currently upgrading to his latest version)?

Larry

 

[dminches]

Thanks, Mike. The 102 may be easier to change over, since there is no tape tension to adjust - just replacing the two tape guides and the head block. Have you tried the Doshi (I have the 3.0 which Nick is currently upgrading to his latest version)?

Larry

Larry, the 3.0 isn't the current version?

 

[Mike Lavigne]

Thanks, Mike. The 102 may be easier to change over, since there is no tape tension to adjust - just replacing the two tape guides and the head block. Have you tried the Doshi (I have the 3.0 which Nick is currently upgrading to his latest version)?

Larry

I've heard the Doshi at shows a number of times, and at Ki Choi's once too. I'd say I have mixed perceptions of it......the best being at Ki's place. I am curious about what it would do in my system.

one big advantage that the King Cello has in my system is that Charles King got some coaching from Herve Delatraz (darTZeel) back then (2009) and was able to install a 'zeel' 50 ohm BNC interface in it for the dart 18NS pre.....which allows for (1) long single ended cables which sound the same as no cables and (2) allow for my RTR decks to be all the way on the other side of the room without any sonic degradation. any other tape preamp will have to overcome that distinct advantage that the King Cello has. I heard the King Cello with RCA's and XLR's back then and it somewhat sucked. so maybe my K/C has a special synergy in my system.

so I have little incentive to look for better tape output electronics. it's pretty damn good.

I will say that with the new dart 18NS preamp that I got last year that the XLR input sounds much, much better. and so this has made a significant step up in the performance of the stock electronics output of the Studers. I have long XLR's running in a conduit in my concrete floor from side to side I installed when the room was built.

 

[dminches]

I am interested in understanding what the zeel interface is. I was always under the impression that for low voltage signals capacitance was critical and the only way to limit it was with a short interconnect. Time to do some research...

 

[dminches]

Does King / Cello have a web presence to view their products? Google isn't finding anything.

 

[Mike Lavigne]

I am interested in understanding what the zeel interface is. I was always under the impression that for low voltage signals capacitance was critical and the only way to limit it was with a short interconnect. Time to do some research...

in the September 2001 issue of Stereophile magazine (page 59-69), Herve Delatraz, before there was any darTZeel company or products, wrote an article about Cable Theory. I am not a techie and this article gets pretty deep in math. Herve used the Engineering School of Geneva and their professor of Physics to assist in testing his theories (Swiss engineers.....hummm). and that was that impedance miss matches in audio interconnects cause smearing (echo's and ghosting).

Herve postulated that very inexpensive cables with perfect impedance matching would out-perform much more expensive cables without perfect impedance matching (my exact experience as well as others).

then later Herve developed the 'zeel' interconnect interface for his darTZeel brand of products to eliminate that smearing. the 'zeel' uses a precise 50 ohm interface on both sides and BNC connectors. Herve claims that any length up to .5 kilometer will sound the same as a .5 meter of the 'zeel'. so far I'd have to agree.

I use 11.5 meters of the very inexpensive 'zeel' that Herve makes for my King Cello interface. it's tiny and I tuck it into a seam on my floor where the hardwood and carpet come together. I also have some much better 'zeel' interconnects (an 8 meter pair for my pre -> amp and a 1.25 meter pair for my digital -> pre ) made by Evolution Acoustics which surpass any other interconnects I've yet tried.

btw; Radio Shack off-the-shelf BNC interconnects work but don't sound nearly as good as Herve's cables he makes. precision in the cable construction and geometry is part of the 'zeel' interface. but Herve's cables are more like $100-$150 (8 years ago....could be a little higher now) per meter or so. about as cheap an interconnect as one can find.

Michael Fremer, who has darTZeel as his reference amps and preamps, has commented numerous times that his inexpensive zeel interconnects outperform other very expensive interconnects in his system. he does not use the 'zeel' typically as he is a reviewer and they skew the results for his readers.

darTZeel products perform just fine with conventional interconnects; but they are 'even better' with the 'zeel'. and compared to the potential cost of interconnects for 'uber' electronics, one can rationalize considerable savings with 'zeel' interconnects in the overall system cost using darTZeel gear.

 

[Mike Lavigne]

Does King / Cello have a web presence to view their products? Google isn't finding anything.

try 'Charles King' or 'Charlie King'. he is a member here on WBF......and is a frequent attendee at audio shows with his tapes and Nagra deck. he lives in the Northeast (Connecticut?)

the King Cello is Charlie's version of the Tom Colangelo 'Cello' circuit that Fred is using too. Charlie added his own power supply design to the audio circuit.

 

[ack]

in the September 2001 issue of Stereophile magazine (page 59-69), Herve Delatraz, before there was any darTZeel company or products, wrote an article about Cable Theory. I am not a techie and this article gets pretty deep in math. Herve used the Engineering School of Geneva and their professor of Physics to assist in testing his theories (Swiss engineers.....hummm). and that was that impedance miss matches in audio interconnects cause smearing.

Herve postulated that very inexpensive cables with perfect impedance matching would out-perform much more expensive cables without perfect impedance matching (my exact experience as well as others).

I read the article back in 2001 but don't recall details, however a quick search turned up an overview in this interview at 6moons http://www.6moons.com/audioreviews/dartzeel2/preamp_4.html where he says:

Q: If you were happy with single-ended connections, why invent another type?
A: There are too many differences among audio interconnects. These differences are not marginal. I examined the problem and wondered if it is really the cable itself or only a problem of mismatch. I conducted an experiment at the Geneva Engineering School and it showed that if you are not matched, you will have some signal reflections. Although these 'echoes' occur above the audible threshold, I found that when you are matched, the sound is much cleaner because you do not have these reflections. It is like the integrity of phase or speed. You do not have any timing errors.

Notice the highlighted sentence - reflections in the ultrasonic range. This is quite true in the digital interface domain, hence the need to perfectly match impedances there (the famous 75 ohm specification for S/PDIF or 110 for AES/EBU - for all the details see http://www.positive-feedback.com/Issue14/spdif.htm), and it's also conceivable to want to filter out ultrasonic aliasing and other noise in those interfaces; hence, a good digital cable is critical.

However, he seems to generalize about ultrasonic reflections everywhere, and obviously that includes the analog domain, but I found no details about that. Moreover, what range does he really consider 'ultrasonic' ("above the audible threshold"), and given all instruments' limited ultrasonic spectra of up to 102kHz or so only, plus the fact that most equipment roll off very early anyway (i.e. they are not wide bandwidth), the devil is then in the details. So you may want to ask Herve for all the details of his research in the analog domain, or someone can perhaps find the 2001 article online. Basically, I'd like to see data that there are indeed reflections in analog interconnections where the input and output impedances of interconnecting equipment are already within a compatible range, and with what cable lengths did he see such alleged reflections.

I also think that cable design has advanced so much since 2001 that a generic statement like this - "that very inexpensive cables with perfect impedance matching would out-perform much more expensive cables without perfect impedance matching" - is probably now over-reaching, as it seems to ignore other problems, like noise pickup, phase issues, etc.

 

[microstrip]

I am interested in understanding what the zeel interface is. I was always under the impression that for low voltage signals capacitance was critical and the only way to limit it was with a short interconnect. Time to do some research...

The DartZeel interface is simply a 50 ohm BNC terminated cable used properly in the audio band. The industry and the research labs have been using it since long ago, I began using it as a student in the 70's and it is used everywhere nowadays as Ethernet coaxial 50 ohm.

Meridian tried using terminated cables with claims similar to those of DartZeel, but with a poor implementation - just an IC buffer and a 50 ohm series resistor.

The problem when using low impedance termination is that such circuit draws several orders of magnitude more signal current than the typical designs, and special care must be taken with all parts of the circuit, including power supply and power distribution. Hervé had to deal with all these aspects in his implementation.

IMHO the magic of DartZeel cable is not due to the 50 ohm interface alone but to the fact that the whole (preamplifier, amplifier and cable) was designed a system to have a defined sound. And yes, I call it magic because, as most of the time in this hobby, cables supposed to sound exactly the same sound different, and some of them sound much better than others!

BTW, I have tried driving non DartZeel amplifiers with an NS18 Dartzeel preamplifier using DartZeel cables, loading the input of of the amplifier with 50 ohm terminators. It sounded better with the 50 ohm terminators than without them, but was not better sounding than premium cables.

At sometime I hoped that the DCS Vivaldi could drive the DartZeel 50 ohm input impedance, as I had read that it has 3 ohm output impedance, but the DCS specification tells that the input impedance should be greater than 600 ohm, 10k?-100k? load is recommended.

 

[microstrip]

(...) btw; Radio Shack off-the-shelf BNC interconnects work but don't sound nearly as good as Herve's cables he makes. precision in the cable construction and geometry is part of the 'zeel' interface. but Herve's cables are more like $100-$150 (8 years ago....could be a little higher now) per meter or so. about as cheap an interconnect as one can find. (...)

Mike,
Unfortunately it is not cheap at all. At the time I discovered that the cable was really expensive - a 10m (33 feet) pair lists for euro 7000.

 

[Mike Lavigne]

I read the article back in 2001 but don't recall details, however a quick search turned up an overview in this interview at 6moons http://www.6moons.com/audioreviews/dartzeel2/preamp_4.html where he says:



Notice the highlighted sentence - reflections in the ultrasonic range. This is quite true in the digital interface domain, hence the need to perfectly match impedances there (the famous 75 ohm specification for S/PDIF or 110 for AES/EBU - for all the details see http://www.positive-feedback.com/Issue14/spdif.htm), and it's also conceivable to want to filter out ultrasonic aliasing and other noise in those interfaces; hence, a good digital cable is critical.

However, he seems to generalize about ultrasonic reflections everywhere, and obviously that includes the analog domain, but I found no details about that. Moreover, what range does he really consider 'ultrasonic' ("above the audible threshold"), and given all instruments' limited ultrasonic spectra of up to 102kHz or so only, plus the fact that most equipment roll off very early anyway (i.e. they are not wide bandwidth), the devil is then in the details. So you may want to ask Herve for all the details of his research in the analog domain, or someone can perhaps find the 2001 article online. Basically, I'd like to see data that there are indeed reflections in analog interconnections where the input and output impedances of interconnecting equipment are already within a compatible range, and with what cable lengths did he see such alleged reflections.

I also think that cable design has advanced so much since 2001 that a generic statement like this - "that very inexpensive cables with perfect impedance matching would out-perform much more expensive cables without perfect impedance matching" - is probably now over-reaching, as it seems to ignore other problems, like noise pickup, phase issues, etc.

I have the article right here next to me. I don't understand it any more today than I did when I originally tried to read it back then. I just wanted to make sure I did not miss quote the conclusion that I recalled.

i just listen and then see where that takes me.

for example right now i have a spare set of 1.25 meter of Evolution Acoustics 'zeel' interconnects i had used with my Playback Designs MPS-5 (it had the 'zeel' interface designed in). to get comparable interconnect performance in a conventional cable i had to go full tilt boggie for the Trinity dac and Golden Gate with $30k each (list price) Tara Labs Grandmaster Evolution w/HRX grounding stations; one set of XLR's for the Trinity and a set of RCA's for the GG. i sold the XLR's after i sold the Trinity. but if i keep the GG long term i will also keep the Tara GME, but if i find a digital player with the 'zeel' i get to sell the Tara which dramatically adjusts the cost of what i might buy.

having everything using the 'zeel' is very cost effective but is not performance compromised. of course; my phono stages are internal with the dart pre so i don't need interconnects for that.

my agenda is that interconnects do not limit performance.

 

[Mike Lavigne]

Mike,
Unfortunately it is not cheap at all. At the time I discovered that the cable was really expensive - a 10m (33 feet) pair lists for euro 7000.

are you speaking about the cable Herve makes or the Evolution Acoustics version?

OTOH 33 feet of Transparent Opus V5 (or other comparable performance cable) would be more than $40k.

 

[microstrip]

I read the article back in 2001 but don't recall details, however a quick search turned up an overview in this interview at 6moons http://www.6moons.com/audioreviews/dartzeel2/preamp_4.html where he says:



Notice the highlighted sentence - reflections in the ultrasonic range. This is quite true in the digital interface domain, hence the need to perfectly match impedances there (the famous 75 ohm specification for S/PDIF or 110 for AES/EBU - for all the details see http://www.positive-feedback.com/Issue14/spdif.htm), and it's also conceivable to want to filter out ultrasonic aliasing and other noise in those interfaces; hence, a good digital cable is critical.

However, he seems to generalize about ultrasonic reflections everywhere, and obviously that includes the analog domain, but I found no details about that. Moreover, what range does he really consider 'ultrasonic' ("above the audible threshold"), and given all instruments' limited ultrasonic spectra of up to 102kHz or so only, plus the fact that most equipment roll off very early anyway (i.e. they are not wide bandwidth), the devil is then in the details. So you may want to ask Herve for all the details of his research in the analog domain, or someone can perhaps find the 2001 article online. Basically, I'd like to see data that there are indeed reflections in analog interconnections where the input and output impedances of interconnecting equipment are already within a compatible range, and with what cable lengths did he see such alleged reflections.

I also think that cable design has advanced so much since 2001 that a generic statement like this - "that very inexpensive cables with perfect impedance matching would out-perform much more expensive cables without perfect impedance matching" - is probably now over-reaching, as it seems to ignore other problems, like noise pickup, phase issues, etc.

ack,

IMHO we should listen to DartZeel great electronics and find if they match our preferences, not spending time reading and arguing about their marketing ... BTW, this applies to 99.99% of high-end products. Surely YMMV!

 

[christensenleif@msn.com]

I´m not sure if I should laugh or cry when I read about cables costing 40K USD....
is the biggest idiot in the selling or buying end of the cable?
best
Leif

 

[microstrip]

are you speaking about the cable Herve makes or the Evolution Acoustics version?

OTOH 33 feet of Transparent Opus V5 (or other comparable performance cable) would be more than $40k.

The standard Dartzeel. Comparison and value are highly system dependent - Ralph Karsten of Atmasphere tells us that 10m Mogami Neglex (~200 euros) has similar properties when used in 600 ohm mode between his preamp and OTL amplifiers. IMHO we should stick just to the facts and then LISTEN!

 

[Fred Thal]

Fred,

I see you use now an integrated circuit in the head preamplifier. Did the Mark Levinson original ML-5's already have this pre-preamplifier close to the head?

No, not seen in the ML-5.

But in the later (20 years later!) Cello A820, the Cello THP-1 used two Burr-Brown OPA 627AM T0-99 packaged FETs.

The ATAE THP-2 uses one TI LME49860.