Zanden DAC noise problem


I am looking for advise on how to solve the noise I get at high sound level from the Signature Dac which is connected to the Zanden transport.The dac is feeding an Einstein preamp driving Atma-Sphere M-60 which is powering a pair of ClassicLoudspeakers T3.3 .The sound is wonderful however when I increase the volume beyond my normal listening level there is a hum .All the other sources,Accuphase800/801 and Meridian861V6, into the Einstein are perfectly quiet.I am not in the mood to send the unit back to Japan,done that in 2008,they did a wonderful job but expensive and takes forever.
I have replaced all the tubes both in the power supply and the main unit,NO ,difference.I have also tried different output on the DAC,aes,and the cat cable.The cat5 works best( Have just replaced with Cat 6)I thought mistakenly that the the original Zanden CAT cable was defective,I have sent it for repair to US vendor unfortunately he will not return the cable nor respond to my requests.However good the Zanden equipment is,the technical support is not commensurate with product quality and price.All help will be greatly appreciated.
ramy
Ramy, I hear you regarding you not wanting to send the unit to Japan. The cost of round trip shipping alone would cost $800 ( even at Zanden's cost) and yes it takes long time to fix too, as Zanden is a small operation company and I hear most repairs are done by Mr Yamada himself. they are busy building their core equipment and are always developing new ones. They invest very long time to develop a new product and it takes years to roll out a new product.

I sent my transport to Japan last Nov to get the drive and clock replaced and the cost was of course equal to buying say a brand new AMR DAC or equal.

Have you ever talked with Fred Nadal of Pureaudio.net? He is pretty good at diagnosing most issues or it least he may help trouble shoot further. Have you tried to write to Eric Pheils?
Hi Nilthepill,
I had similar experience in 2008 I sent that same DAC to Japan,they did an excellent job at an exorbitant cost.I did contact Eric he is always willing to assist,but his recommendation was change tubes or send to Japan.I had a different suggestion from another audiogoner who has experienced the same problem that it may be a defective choke.I just wish that we could have access to experienced audio electronic technician that had the skills to do minor repairs of overseas manufactured products with no US service and even more important the ability to repair classic electronic components of now defunct companies such as Cello.
Hi Nilthepill,

Great to hear from you. I am glad to hear you still are using your Zanden. You gave me good advice about Zanden...i still have my DAC but have yet to get the Transport.

I have heard there are upgrades available to DAC...have you ever upgraded yours? Was curious what you may know about these upgrades...from vintage 2007. Thanks for any advice!

Have you heard the STahl-Tek Vekian Opus digital?
Ramy,

It sure would be great to have authorized Zanden service centers here in US. It would be highly cost effective. Before I sent my transport to Japan, I did try to contact Brooks Berden here in LA area and they said they could fix my Transport problem and that they have repaired Zanden products in the past. You may want to talk to Brian Berden to check if they could fix your problem. (Unless it is already fixed). If you do pl post the findings and how it was repaired.

Hi Lloyd,
I think last time you or one of my audiogn friend from Netherlands asked me the same question reg DAC upgrade and i checked with my dealer Fred Nadal and he said mine was the latest and greatest. However, I am meeting with h today and ask him again. I am going to audition the new Zanden Integrated amp and audition the Zanden Power cables. I am on my way to install all my cabling from Zanden. I have , so far, installed all i/cs, waiting for speaker cables to be rolled out. I think they are really excellent cables at surprising 'reasonable' pricing. You both should look in to it.

No I have not heard STahl-Tek Vekian digital. Have you? How does it compare with the Zanden Signature DAC?
Hi Nilthepill,

Sounds very interesting! I have spoken with ERic Pheils who said Mitsubishi tested the new Zanden cables and found that with the Safety Wave fabric in it...they had 5db lower noise floor...the guys at Mitsubishi were apparently dumbfounded.

Enjoy!

As for Stahl-Tek...i have heard only the original Vekian 2 years ago. The new Opus is supposedly far better, more organic, better sense of live music in the upper treble.

That said, the Stahl-Tek Vekian is the first digital ever to make me consider trading in my beloved Zanden. I have heard Scarlatti, Emm CDSA, Meridian 808.2i, ARC CD7, CD8, Wadia s7i, Metronome Kalista Ref/C2A...none have tempted me so far.

But as some will be sick of reading...i have been trying to speak with everyone i can think of about Zanden v STahl-tek...until i can get a shoot-out arranged hopefully in about a month's time.

The Stahl-Tek has a Scarlatti-like low noise floor, the ability to keep tempo/pace in complex passages which enables you to totally and easily understand contrapuntal themes which are often lost on other digital playback. I have not heard such effortless delivery of multiple individual themes of music so you can follow each one before.

At the same time, my Zanden is older than yours. I have heard the latest Zanden but not for long enough and not in a direct shoot-out with Stahl-Tek.

But i have spoken to more than a few guys in Asia who owned Zanden and have traded in for stahl-tek. so it does make me think! honestly, i could be very happy with Zanden (as well i should!)...but if i am going to 'double down' and buy a second-hand transport...i may as well be sure about this. STay tuned!...;)

Pls post your findings about Zanden cables when you hear them!!!!!!!!!!