[Vazzee]

Many thanks!

Have a great evening!

 

[oghoter]

On my unit, it switches between a pair of RCA inputs (on the right, as seen from the front), and a minijack input (on the left).
 
This little amp (which I use mainly to enhance active speakers) still works like a gem in my chain:
Digital files > DAC > Jade > Sony SRS-ZX1 speakers.
It can probably be tweaked to new heights.
I compare with my large system OTLs (Atma-sphere MA-1 v 3.3), and it works well, in my home office context.
 
Two rules appear, from this usage.
-The better the digital files and the DAC, the greater the benefit of the Jade.
-The more of the total amplification that the goes to the Jade (to a limit), the better the sound
 
I bought the Jade mainly as a headphone amp, and got a balanced cable from Auditotailor, which made the HD600 sound great indeed.
However, the cable broke down, and also the 600 felt uncomfortable in the longer run, so I sold them, and bought a pair of AKG701 instead - which I generally like more.
But I have never tried them with balanced cable. I don't know, can the 701 be modified to run balanced with Jade?
 
Tubes: in my context, all fairly good tubes work well in the Jade, they mainly give me what I want. Listening more deeply, I have come to prefer a combination of NOS RCA output big bottle tubes (or perhaps GEC, not sure) and a NOS Telefunken driver tube.
 
All the best,
Oystein

 

[Vazzee]

Thank you for your help!
 
I find it great to see that how a fairly priced gem can bring so much joy into peoples lives!

 

[oghoter]

Yes - this is the case - a gem indeed. I had a scatching noise problem with the Jade some years ago but it was repaired since I was present when the service man opened the box. He could not find any fault, neither could I. Then I asked, could he look also at the top of the print card. There, we found a broken connection. It has run trouble-free ever since.

 

[oghoter]

Today I cut the plug off my AKG 701 and soldered two TRS plugs, to run it balanced from the Jade. I remember my HD600 sounded very good after I got a balanced cable from Audiotailor but it broke down after some months. I have read it is an easy mod on the 701. Well, yes and no. I followed the rather cryptic instructions from Joe earlier in this thread, plus debate on the 701. So I soldered the yellow  lead to the tip (+) and the black lead to the ring (-) on one TRS plug, and the orange to the tip and the white to the ring on the other TRS. I did this after fiddling around for a while, using my fingers plus tape on the naked plugs, trying to get correct sound, since there have been reports that the connections of these leads in the headphone can vary, and opening it is difficult. Ok, well done, I thought. But then I noticed: I had mono! Oh well. But - if I pull one of the TRS plugs a bit out of the Jade contact, I get stereo. This must mean that the tip of the plug touches the ring in the contact. The sound is weaker than in mono (maybe, since mono is a sum of the two channels), but seems OK otherwise, not out of phase. Anyone else with experience at this point?

 

[Sraitsa]

Would anyone happen to have the general fix for the hum that can appear with the Audiotailor Jade that develops? I would believe that it is related to the grounding. The hum seems to be not altered by volume and is present of both channels.

 

[elwappo99]

Would anyone happen to have the general fix for the hum that can appear with the Audiotailor Jade that develops? I would believe that it is related to the grounding. The hum seems to be not altered by volume and is present of both channels.

This is an old thread indeed. Sounds like it could be a ground loop issue. Remove the RCA input cables. If that removes the hum, you can get a ground loop isolator to help. If it doesn't, try the amp in a few different outlets or a completely different house.

 

[MLA]

Depends on your unit. The early production units had a grounding error on the pcb that required cutting a trace on the pcb to fix. I think most of those were sent back and fixed by Joe, but if yours happen to be an unfixed one, the hum should not be developing; rather, it should be there immediately at turn on. Solutions to that (with pics) are available early in the thread.

If it's a later unit, then that is fixed and you have some other issue. If it actaully develops over time rather than being present immediately, first isolate it to the actual amp as elwappo99 suggests (remove all inputs), and if the hum is still there I'd suggest swapping the tubes out before doing anything more drastic.

 

[Sraitsa]

Depends on your unit. The early production units had a grounding error on the pcb that required cutting a trace on the pcb to fix. I think most of those were sent back and fixed by Joe, but if yours happen to be an unfixed one, the hum should not be developing; rather, it should be there immediately at turn on. Solutions to that (with pics) are available early in the thread.

If it's a later unit, then that is fixed and you have some other issue. If it actaully develops over time rather than being present immediately, first isolate it to the actual amp as elwappo99 suggests (remove all inputs), and if the hum is still there I'd suggest swapping the tubes out before doing anything more drastic.

Thanks for the response. I guess that it must be either a capacitor that has gone faulty or a ground solder joint has gone (valves were the first to be tested). I am certainly leaning towards the solder joints as the ones around the main socket aren't looking good at a glance. Locating the circuit diagram would certainly make life easier.

 

[MLA]

Never saw a diagram so unfortunately I think you’re on your own there... Reflowing all the joints is quick once you take it apart, so that’s probably a good start. Never got hum from a bad cap, only hiss, but that may be a matter of acoustic semantics The upgrade coupling caps (if you have those) Would be easy to desolder and test with the unit open.

 

[oghoter]

Yes, this is an old thread - but that may also be taken as a positive sign. Jade remains an interesting preamp, and in my case, it runs very well, making my home office active speakers sound way better than they were supposed to. But then, they are single driver speakers following up the minimalist philosophy. My unit - bought from Joe in 2009 - does not have the hum problem described above. It has given a lot of pleasant and useful service, rising to the occasion, when the source feed is better, like DSD from my Fiio DAP, or when Tidal has succeeded in a good "master" recording, it shows the difference. The OTL advantage is larger, the better the source. So for me, it is a keeper.

I have a question for you. The Jade needs a bit of service soon. There is some scratching in the volume control, and jack outputs. So I wonder, can a repair be combined with a few improvements, at a service shop. What would be the two-three things to do - components to change - in terms of sonic upgrade?

 

[MDR30]

A couple of months each year I listen to this amp regularly only to discover how nice it sounds with my go-to-headphones. I've driven it balanced almost from the beginning and the spaciousness is admirable. Also gives me the opportunity do some tube rolling which I seldom have time for (and also to sell off some tubes). Check this album out, a minor masterpiece with a sound world made for headphones:



Right now the Audiotailor is driven by a Telefunken ECC83 and a Mullard 6AS7G/6080 with excellent results.

A pity we've not seen the daylight of this OTL amp promised by Joseph Lau in 2013:

New Headphone amp are under developt. It is upgrade from Jade.
12AX7 x 1 , 6AS7 x 2 , 6AS7 Loading by CCS. Top model will use Reed relay base 42 steps, step attenuator. It is 2db/Steps. Very low pop noise. It may be will release around 2 ~ 3 weeks. Other hybird Jade also will comming soon.

 

[MDR30]

Inspired by Hazy_Joe I did some experiments with tubes and adapters which turned out quite interesting. I have mainly tried members of the 12A_7 family for the driver stage, and some of their predecessors (6SL7, 6F8G - below).

But why not widen the field?

Mullard turned out to provide some fine combinations. The 6080 output tube above with a ECC 40 (adapter) sounds very nice, big soundstage and nice power delivery despite lower gain than 12AX7.

As the anode voltage of the Audiotailor is 126V it is also possible to use an ECC88 (adapter) which has an upper limit of 130V. A very homogeneous sound.

But one of the big surprises was the Sylvania 6CG7, a medium mu tube that comes cheaply. I recommend you to try it, very lively without being aggressive. Here with a Tung-Sol 5998.

The power tube above is among the best, but it does not reach the same level of detail and expansion as the Tung-Sol 7802 tube, rare as hens' teeth. This is at the moment running with a Voshkod 6N2P and I won't change that for a while.

This is a very nice amp.

 

[MDR30]

Switched driver tubes so many times that the socket wore out, irritating intermittent pin contact.

Replaced it and all is fine. The amp still impresses, despite competition from a handful other very good amps.

 

[oghoter]

Thanks for nice pictures!
The Jade continues to do a remarkable job in my home office system, too. After some repairs some years ago it now performs fine, with NOS tubes (Telefunken driver, RCA output) that enhances the musicality of the unit. I use it in two roles:
A - as link in my home office amp chain (between a Topping DAC, and Arche amp and speakers)
B - as headphone amp (mostly for Nightowl and Nighthawk phones)