Perhaps contacting the seller might prove fruitful , dealers often drip feed a set of valves such as these onto the market until they are sold, then list another quad , he may be able to supply an Octet.
Ron’s New System
- Thread starter Ron Resnick
- Start date
No problem jadis use auto bias , the resistor determines the operating point.
if one of these does not produce exactly the same value, perfect matching the tubes does nothing. I wouldn't see it that closely. A friend wanted 16 new pieces of the same KT 90 for a convergent amp jl 1 monos. It took three years.
Exsample ja80 shematics
P.s
when if someone uses this ja 80 please change the resistor to 150k-220kohm its a ticking time bomb.
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Yup It is known ….However , For my part I would still prefer to purchase at least the 2 x Quad sets both matched A : they should age at the same rate and B : that should make them more attractive should one A; merely stockpile them then sell them on, or B: One can be offering them as a set Pre used but with matching emissions Or ultimately The JA100’s supplied with used but with matching emissions output valves.
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I wouldn't use the new Ei KT 90 at all, glowing gold is an investment for live
I wouldn't use the new Ei KT 90 at all, glowing gold is an investment for live
What do you mean by "new" Ei KT90? I thought the Ei KT90s were manufactured before the war in the early 1990s.
Has there been a recent "re-issue" of the Ei KT90?
Ei yugoslavia in Nis closed in 2014 there were over 200,000 tubes of different types in the warehouse. the ones on eBay are unused originals.
P.S
Whoever took them when the factory was dismantled will become a rich man
I know that some of the best sound I got from Jadis JA80's was using hard to source , very expensive NOS MOV KT88's well matched tubes.
But IMO if you need hard to source , very expensive NOS valves to evaluate a tube amplifier something is wrong with the amplifier.
Gotham GAC-4/1 is exactly what I am using presently on the JA100s. If you prefer the tonality of the Gotham, maybe I should just stay with the Gotham and not switch to the Belden 1192A to conform it to my balanced runs to the woofer towers.
Note that the Gotham cable lifts the shield at the downstream component end.
The VTL Siegfried II uses zero global feedback. What makes you think it is using a lot of feedback?
I am already using the lowest damping (lowest local feedback) setting.
Ron, I guess it's working well.
have you tried the GAC-2?
I am thinking of trying GAC 4/1 or 2. Not sure which one.
I go between 5m Nordost Tyr and Mogami 2549.
It would blow up in your face if it didn't have any, with that many tubes.
I never said global feedback. You and VTL both say it uses "local" (nested) feedback. You can call it low because of the setting but for a tube amp it certainly isn't low like an SET or something.
You don't get 0.01% distortion without plenty of feedback. In fact all modes it has very low distortion in. Compared to Lamm it has no less than 10x less distortion, to give you a rough idea of feedback.
Ron, I have a set of those Black Treasure 6CA7 from about 10 years ago (who knows if the current ones are the same) and they are very good, I actually prefer them in my amp to Mullard xf2, and they have been totally reliable (again who knows if the new ones are the same). The Mullards are just too warm. KT77 is another interesting option. I haven’t tried the Russian Gold Lions, but the JJ KT77 is a good sounding tube but brighter (and more resolving IMO) than EL34 (except for maybe the 10 year old Black Treasures)
Since the Jadis can take bigger KT tubes and EL34, can it do KT66? Now that in my opinion is the best of all these tube types, with great resolution, dynamics and the best treble. Tight accurate bass, not the warmth and bloat of EL34 or KT88. More like a higher resolution KT90, but half the power. The Russian “Gold Lions” are good, but GEC KT66 (either grey glass or clear) are fantastic tubes. Still decent supply of good testing tubes around since they seem to last forever.
Starquad wiring instruction:
In order to benefit from the Starquad concept you need to wire the 4 conductors for you balanced audio cable as follows: (See wiring diagram below)
Bundle each opposite (Star) conductor together, we made colour code easy to identify the opposite conductor. (red/pink and white/ivory each belong together.)
Pin2= red&pink (Signal+), Pin3= white&ivory (Signal -). Pin1= shield 1&2 =Ground
Put each a few strands of each layer of the shields together to ground Pin 1 should you not have space for all shielding strands.
Cut away any spare strands from the shields and secure that no loose strands are hanging around. Use a shrinking tube to avoid short circuits.
We do not recommend putting any ground to the body shell on either side of your XLR line. The connector shell will get to ground once plugged into a receptacle.
RCA/Phono/Jack unbalanced wiring:
Many clients use our 4 conductor cable also for unbalanced interconnects. In this case we recommend to only use 2 conductor (red&pink) for your signal and put all other wires or parts thereof to ground with the shields. This will increase your noise protection! However for unbalanced application we do have our perfect unbalanced wires 1001x, and 1000x.
Stereo & 2 Channels application:
We actually do not support the idea to use a Starquad cable for stereo wiring, however it will be done and can be made with acceptable compromise regarding crosstalk and similar. If you use the cable as stereo line, use red/white for channel 1 and pink/ivory for channel 2. And again, all the shields to ground but not to the body shell of your connector.
Check our perfect stereo cables 12001/13001 or our conductor shielded Starquad 11301 for real quality stereo wiring!
Doesn't sound like you should be using it as an interconnect. Imo.
no idea, hence the question
20 Foot - Gotham GAC-2 AES/EBU (Purple) - Low-Loss, 2xCore 2xShielded Balanced Digital & Analog Audio Cable w/Neutrik Gold Male to Female XLR Plugs - Custom Made by WORLDS BEST CABLES : Amazon.com.au: Musical Instruments
20 Foot - Gotham GAC-2 AES/EBU (Purple) - Low-Loss, 2xCore 2xShielded Balanced Digital & Analog Audio Cable w/Neutrik Gold Male to Female XLR Plugs - Custom Made by WORLDS BEST CABLES : Amazon.com.au: Musical Instruments
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Tyr is a little more vibrant and forward but can be a little hot in the top end. 2549 more relaxed, bot quite so much detail - not as hot in top end.