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Jadis bias values and customer service

Hello all,

Had a conversation with Jadis today in French as I reside in France. I have a DA-7, a DA-5 and a DPL2 since 1996 and needed some information on KT120 tube compatibility and bias values. Simple questions...

JADIS officially and categorically refused to answer my questions and invited me to take my equipment to a technician (of which there are not many servicng Jadis products...). Yes, that is correct, no simple information was given to me as a faithful customer since 2 decades.

I assume, for those of you in countries other than France, that your dealer or retailer could obtain any information you might need, but my retailer has been closed for many years...

For those of us who can safely perform basic operations, like adjusting bias on fixed bias amps(!), Jadis' attitude is not putting the customer first, but rather its network of retailers or technicians. Personally, I don't agree with this policy.

Part of what we enjoy about our hobby and the various equipment we have, is the very ethos of the manufacturer. I feel that Jadis has taken a serious hit for mistaking its customers for imbeciles.

Good listening to all... 
128x128david60
8 responses Add your response
jafant's avatar
jafant
19,578 posts
 
Thank You! for sharing your story- david60

It is imperative to post both positive & negative experiences when interacting w/ these manufacturers. Dealers/retailers also fall into this discussion as well.  You performed a great service here by shedding light on this important matter.  Jadis is a popular brand and the hope is that another owner will view your post and provide the assistance needed.
testpilot
922 posts
 
I assume that Jadis has not tester their amps with the KT120 tube, therefore, they are unable to give you an opinion.  Audio Research was the same way with some of their KT88 based amps when the KT120 came out, but they did not refer you to an outside tech, they just said "no".
gwalt
162 posts
 
I once owned the JA30 since purchasing the new JA30 MKll. They answered my questions via email I had on tubes within 24 hours about the variety that can be used. This was some 6 months ago. Just saying this contradicts david60 experience.
david60's avatar
david60 OP
5 posts
 
Sorry @gwalt but your experience does not contradict my experience with Jadis. You did not indicate requesting BIAS VALUES for your amplifier with selected tubes. It is on this point where Jadis invoked a LAW (!) stating that they could not and would not give that information for a fixed bias amplifier for my "own safety". Therefore Jadis was perfectly unwillingly to help a customer. Note that these exchanges were conducted in French (as I am French) in both writing and by telephone, therefore there was no misunderstanding about the subject at hand.
UPDATE : since then, and without Jadis's help, I have determined the correct resting current values and adjusted the bias on a new quad of tubes. This was performed in spite of Jadis's concerns for my health and I have survived the ordeal to write this response. Have a good one.
georgehifi's avatar
georgehifi
10,312 posts
 
Carefull.

KT120 tubes can draw up to 500mA more than a KT88 on the heater current, x this by the amount of tubes and you have a lot more stress put on the heater supply, and it could sag the 6.3v needed. In a Rogue poweramp the KT120's split the bridge rectifiers in half after a month or so.

Cheers George 
bdp24's avatar
bdp24
9,787 posts
 
Thom at Brooks Berdan Ltd. in Monrovia, CA has a lot of experience servicing Jadis products, of which BBL is a dealer. He’s in the store on Wednesdays and Saturdays, is a very knowledgeable electronic engineer and technician. and a friendly, helpful guy.
david60's avatar
david60 OP
5 posts
 
@georgehifi Thanks for the heads up. Just using KT88s so no worries to be had with KT120s.
@bdp24 Thanks for info, CA being a long way from here, never heard of him. Will keep the contact for the future. Thanks to you both.
georgehifi's avatar
georgehifi
10,312 posts
 
Of all those tubes mentioned in this, by far the best sound I got was from the white box "Mil Spec GE-6550" with the green label, interesting was the glass was inert because it was twice the thickness of any other tube.
https://img.ruten.com.tw/s2/c/d2/58/21544929147480_714.jpg

Still available, not cheap.
http://yahoo.aleado.com/lot?auctionID=e215700969

http://www.worthpoint.com/worthopedia/ge-6550a-jan-quad-set-green-169377351

Cheers George
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