Jadis JA-200 Mk. II Amplifiers

[Argonaut]

Which kind of choice or system involved?
I started in 1973 and until now i did different experience and choice and always involved the system

I was mainly curious of your reasoning behind Making such a highly critical statement about the Ref250...by MKII I presume you are talking about Ref250se .

Or am I to conclude a sweeping generalisation that you prefer amplification that's adds coloration and attenuation to the origional recording and sounds 'nicer' to your ears! If that's the case then buona fortuna, however that does not make the Ref250se 'Not fit for purpose' in conveying accurate fidelity to the origional recording IMHO

 

[Taiko Audio]

Hi Ron,

I currently use a pair of VTL MB-750’s in my development system driving a pair of Kef Blades. My guess is the “slow sound” described by some here applies to running them in triode mode with the stock VTL branded 6550 winged c’s and driver tubes. I use them in tetrode mode with TAD (chinese) KT-88’s and driver tubes and I dont think theyre slow at all. The combination does provide for extremely low distortion levels, THD measures below 0.1% down to 70Hz increasing to 0.2% below, THD+N is unavoidably around 1%, still not bad for tubes.
We have Jadis JA-80 mk-1’s in house, currently on loan to a client but when they return I’ll hook them up and report back. I dont think they compare but have not done a direct A/B before. The Ayon Orthos might be an interesting alternative. I recommend threading carefully as the old 750’s are obviously not flawless but they can be very capable amps when setup right.

 

[gian60]

What I posted is not ref 250 but is
D250 that was produced in 1983/84
This photo is my system in 1983/84

 

[Argonaut]

What I posted is not ref 250 but is
D250 that was produced in 1983/84
This photo is my system in 1983/84

Thank you for the qualification Gian, which makes for an clearer understanding of your consideration, my apologies should I have come across as somewhat terse in my responce to that consideration. buona giornata.

 

[Mike Lavigne]

Very interesting, Mike! As long as you were considering venturing back to Europe did you also consider the comparable Austrian Ayon Audio amplifier?

the Ayon was on my radar in the peripheries (maybe a bit less than the Jadis), which is no dig on Ayon at all. i did briefly take a stab at acquiring one particular tube amp, the WAVAC HE-833 (likely the V2), but then i found the musical connection i'd been seeking with some system tweaks and my tube lust cooled. it only cooled, i still have tube lust. i always think about this or that tube amp, but the reality of my system priorities rears it's head. since that flirtation with tubes, I've acquired the MSB Select II, the Tripoint Elite, and i'm on my way to acquire the AS-2000 (and other more modest additions). so i could have pulled the tube amp trigger if it was important enough to me.......obviously i'm just a tube amp wanker/lurker......so pay me no mind.

 

[BMCG]

it was on my radar in the peripheries, which is no dig on Ayon at all. i did briefly take a stab at acquiring one particular tube amp, the WAVAC HE-833 (likely the V2), but then i found the musical connection i'd been seeking with some system tweaks and my tube lust cooled. it only cooled, i still have tube lust. i always think about this or that tube amp, but the reality of my system priorities rears it's head. since that flirtation with tubes, I've acquired the MSB Select II, the Tripoint Elite, and i'm on my way to acquire the AS-2000 (and other more modest additions). so i could have pulled the tube amp trigger if it was important enough to me.......obviously i'm just a tube amp wanker/lurker......so pay me no mind.

Until a LAMM ML 3 just appears....next to the Dartzeels

 

[Mike Lavigne]

Until a LAMM ML 3 just appears....next to the Dartzeels

i don't want to send this thread into extreme OT orbit.....so i will leave that alone.

 

[rsorren1]

Hi Ron. I heard the Jadis JA-200 MKII with Jadis preamp and phono stage at AXPONA 2017. Here is a link from Stereophile.
https://www.stereophile.com/content/jasons-day-one-continues-one-step-closer-oz
I was able to sit center for the demonstration and recall thinking this system sounded really good. The sound was rich and warm, open, had 3D characteristics. Female voice was very good as I recall but can’t remember what I heard. Phillip O’Hanlon’s room was one of the better presentations I heard at the show. The only VTL experiences I’ve had are with Siegfried and I would say that a full VTL system (Siegfried, 7.5 pre, 6.5 phono) that I have heard on Wilson Alexia would be a contender against the overall sound of this system in the same room with the same speakers. My current personal references are Zellaton/CH Precision so the Jadis system sounded less dynamic, extended, and real to me but that is just my personal preference at this time. The Jadis system with Vivid was impressive no doubt.

 

[microstrip]

http://www.hifiplus.com/articles/jadis-ja-80-mk-ii-mono-valve-power-amplifier/

Alan Sircom's take on the Mk II JA 80

Thanks - it confirms what I had read in french magazines - the changes of the ja 80 were minimal. Quoting from it:

"However, to engage in this kind of valve substitution (KT150's) does require sending the Jadis amplifiers in for subtle changes in the internal wiring of the valve seats.
(...)
The rest of the design remains almost identical to the original JA-80, because change for its own sake is anathema to Jadis. The other valves in the circuit are an ECC83 as line driver and a ECC82 as phase shifter, which are flanked by four blue coupling capacitors. "

 

[microstrip]

Hi Ron,

I currently use a pair of VTL MB-750’s in my development system driving a pair of Kef Blades. My guess is the “slow sound” described by some here applies to running them in triode mode with the stock VTL branded 6550 winged c’s and driver tubes. I use them in tetrode mode with TAD (chinese) KT-88’s and driver tubes and I dont think theyre slow at all. The combination does provide for extremely low distortion levels, THD measures below 0.1% down to 70Hz increasing to 0.2% below, THD+N is unavoidably around 1%, still not bad for tubes.
We have Jadis JA-80 mk-1’s in house, currently on loan to a client but when they return I’ll hook them up and report back. I dont think they compare but have not done a direct A/B before. The Ayon Orthos might be an interesting alternative. I recommend threading carefully as the old 750’s are obviously not flawless but they can be very capable amps when setup right.

The bass of the MB750 only showed its limitations when compared to modern VTL's, Atma-sphere's or for example recent Audio Research amplifiers. I always used it in tetrode mode and most of the time in balanced mode. Today I feel guilty of not having upgraded it - but upgrading it needed around 30 signal capacitors and as the original capacitors were small, typical high quality ones from Mundorf or Vcap would not fit the space. The relative lack of detail playing at low levels extended along the bandwidth.

Unfortunately the balanced input was a late poorly implemented add-on - I only discovered it little time before parting with it.

I measured my units - the output transformer was really good , wit low distortion at low frequencies, but overall much higher distortion that current amplifiers. The power supply was exceptional - there separate power transformers for filaments, output power and input/driver.
None of the power supplies was regulated, as in modern VTLs.

I am reporting on sound with Wislon, SF Aida's and Soundlab's - surely with other speakers it can sound different.

 

[DaveyF]

Thanks - it confirms what I had read in french magazines - the changes of the ja 80 were minimal. Quoting from it:

"However, to engage in this kind of valve substitution (KT150's) does require sending the Jadis amplifiers in for subtle changes in the internal wiring of the valve seats.
(...)
The rest of the design remains almost identical to the original JA-80, because change for its own sake is anathema to Jadis. The other valves in the circuit are an ECC83 as line driver and a ECC82 as phase shifter, which are flanked by four blue coupling capacitors. "

Micro, what Alan is referring to is a change away from the KT150's if the owner so wishes ( although I cannot understand why anyone would do that, unless the KT 150's become unobtanium).

Sure the heart of the amp is basically the same as the JA-80....its not a brand new amp across the board...and why would it be? ( so the amp shares the same chassis, the same basic look, etc) Instead, Jadis has modified their design with better transformers, larger caps, better wiring, and the ability to utilize the new KT150 tube. Is there a problem with that?

 

[KeithR]

Micro, what Alan is referring to is a change away from the KT150's if the owner so wishes ( although I cannot understand why anyone would do that, unless the KT 150's become unobtanium).

Sure the heart of the amp is basically the same as the JA-80....its not a brand new amp across the board...and why would it be? ( so the amp shares the same chassis, the same basic look, etc) Instead, Jadis has modified their design with better transformers, larger caps, better wiring, and the ability to utilize the new KT150 tube. Is there a problem with that?

+1. I'm not sure the point here and micro uses the opposite argument for other electronics.

Just the transformer difference to accommodate the KT150 is quite a difference - as it is on my ARC Ref75SE. They've also added auto bias, fused resistors, etc. To say there is little difference from a 1983 amplifier i think is misguided at best.

 

[KeithR]

What I posted is not ref 250 but is
D250 that was produced in 1983/84
This photo is my system in 1983/84

Why are we comparing early 1980s amplifiers to a current, recently redone product?

 

[DaveyF]

Why are we comparing early 1980s amplifiers to a current, recently redone product?

+1

One of the big problems I think on this and so many other forums, is that members who have not heard the current/latest gear in question, assume (incorrectly) that the piece that they either owned or heard decades ago is representative of the current offering.

I have numerous discussions with posters about the SQ difference between the current Linn LP12 Klimax and the old model that they remember hearing back in the day. Unfortunately, these guys have not heard a new model or even one close...but they all have an opinion on the sound of the current piece!!
Same goes here for the new versions of the Jadis gear. IMHO, the mk 2’s are a very different animal than what the company was producing in the past...certainly so when it comes to the SQ!!!

 

[Ron Resnick]

When I went to Joel's (who writes for 6 moons), I found the Luxman to be much better to his Ypsilon hybrids on the vivid G1. Joel further mentioned that he had reviewed the Ayon Orthos XS and found them to be the second best, after the Luxman, on his Vivid and also on Maggie 20.7. I therefore bought the Orthos XS and shipped them to Justin to try on his duetta.

They were good on duetta but not great. To do dynamics you had to shift them from triode to pentode. I found that the Parasound which we compared it directly with, while lacking refinement, would wake up the panels more. So I didn't find them special but maybe should not have tried on duetta.

My favorite push pulls with jadis would be the AR 250 SE (having compared them with MSB and the VTL with MSB). AR probably better for drive on tougher speaker.

I would any day choose Luxman and/or Vitus (i mention these two because they are more valve like in their sound in SS amps for your tastes) over PP valve amps for speakers that require the current and power, as I expect ribbons to be. If you wanted to keep a transistor out you should have gone horns

Thank you but you are talking "apples and oranges." The Apogees are much tougher loads than the two meter ribbon in the Pendragons. Imagine if you disconntected the planar magnetic midrange and woofer in a Magnepan speaker and had only the tweeter ribbon to drive.

Historically the Jadis JA200 was considered a super-classy way to drive Infinity IRS V ribbon panels (this is how I heard IRS Vs in the main reference room at Lyric Hi-Fi in 1988).

Audiocrack uses the 40w or 50w Kondo amps (if I remember correctly) on his Genesis 1.1s.

So the two meter ribbon in the Pendragon is easy to drive compared to the multi-way Apogee with big woofer ribbons.

(Put differently, you ain't gett'in me to use solid-state on the Pendragons!)

 

[Syntax]

+1

One of the big problems I think on this and so many other forums, is that members who have not heard the current/latest gear in question, assume (incorrectly) that the piece that they either owned or heard decades ago is representative of the current offering.

I have numerous discussions with posters about the SQ difference between the current Linn LP12 Klimax and the old model that they remember hearing back in the day. Unfortunately, these guys have not heard a new model or even one close...but they all have an opinion on the sound of the current piece!!
Same goes here for the new versions of the Jadis gear. IMHO, the mk 2’s are a very different animal than what the company was producing in the past...certainly so when it comes to the SQ!!!

Yes, the next upgrade is always the game changer.

I always ask myself why the dealers/reviewers didn't hear the shortcomings before, when they tell everybody how much better the new version compared to the one before is ....

 

[Calle_jr]

Micro, what Alan is referring to is a change away from the KT150's if the owner so wishes ( although I cannot understand why anyone would do that, unless the KT 150's become unobtanium).

Sure the heart of the amp is basically the same as the JA-80....its not a brand new amp across the board...and why would it be? ( so the amp shares the same chassis, the same basic look, etc) Instead, Jadis has modified their design with better transformers, larger caps, better wiring, and the ability to utilize the new KT150 tube. Is there a problem with that?

+1. I'm not sure the point here and micro uses the opposite argument for other electronics.

Just the transformer difference to accommodate the KT150 is quite a difference - as it is on my ARC Ref75SE. They've also added auto bias, fused resistors, etc. To say there is little difference from a 1983 amplifier i think is misguided at best.

Well, I changed myself for KT120 on my mk1. It's an easy operation and wouldn't even require sending them to Jadis.
There's autobias on mk1 as well, and there's a fuse for each tube on mk1 as well.

What else was different?

"Better transformers", "larger caps", "better wiring"? That wouldn't be problem if it was true.

I'm only asking because I want to know.

 

[Ron Resnick]

Your mono and stereo Danon did choose Vitus over Nat to drive his Gryphon? And Greg baron said his client replaced his all NAT with all Dart and both he and the client found out much better? I forget the speakers

Yes, Dato' Danon did choose Vitus to drive the Pendragons (and now the Kodos).

I do not know the Greg story to which you refer.

But I will add another data point in support of your point: Michael Fremer chose the darTZeel amplifiers over VTL Siegfrieds, preferring the slightly more transparent, slightly less bloomy side of that knife-edge between tubes that get close to the tube/solid-state neutrality line and solid-state which gets close to the tube/solid-state neutrality line. I make that fine decision the other way.

My ears are ideologically opposed to transistors in the signal path, just as they are ideologically opposed to digital. (Mixed metaphor? I guess my brain is ideologically opposed and my ears are practically opposed?

That is what makes horse racing. That is part of what makes this hobby largely subjective and endlessly fascinating.

 

[Calle_jr]

Historically the Jadis JA200 was considered a super-classy way to drive Infinity IRS V ribbon panels

That must have been a nice setup!

 

[Ron Resnick]

A friend and fellow a’phile owns Ayon. I had several options to consider in the amp department before the Jadis JA 30mk2 became available..once the Jadis showed up,the decision was obvious at that point. The Ayon were never really in consideration, they don’t hold candle to the new Jadis IMHO.

Even though I had not heard the new JA30mk2 at that point ( I doubt more than a mere handful of people in the US had either) I had heard the JA120’s and I knew these new amps would be even better!!

Interesting, Davey, thank you.