Wadia 850 and Spectral DMA 150 matching without pre-amp


Can I directly connect a Wadia 850 to a Spectral DMA 150 without using a Spectral pre-amp?

I understand that the Spectral pre-amp give very current output (upto 1 amp) and a maixinum voltage of 100v peak for the power-amp. The guy at my local audio shop advised that Wadia/Spectral power amp direct connect would give poor dynamic range. However, I am not quite understand the reasons behind it.

Would anybody give me some advise.
vtin
I am running my 860x direct to My krell amp with great results after listening both ways I sold my krc3 You will loose switdhing capabilities but I feel what you gain it is worth it. I say try it and listen for yourself. All you have to lose is your pre.
I have a Wadia 850 that I run into my Krell monoblocks and it works just fine. The Krell amps needs only 2 volts to reach its maximum power. If you are going to connect the 850 directly into the DMA 150, use balanced outputs. The 850 will provide up to 1/4 of an amp but it really doesn't matter since the input impedance of most amps are 50 to 100K Ohms so it only needs the voltage. For most amps, preamp out of 2 to 5 volts is more than enough. Give it a try you just like it.
I have received the following email from other Audiogon member:

" I have a Wadia 850. The dealer I bought it from was also a Spectral dealer. I asked about that possiblity. They told me that they had DAMAGED a Wadia 850 by directly connecting it to a Spectral amp.

I think the problem is that the Spectral input will force the Wadia into ocillation at high frequencies. Most amps cut off above 22Khz or so, but not the Spectral. Certain cables might attenutate higher frequencies.

Be careful trying this!! "

I have consulted a few high end audio experts and they all advised me that the above problem is not possible.

Your advise would be much appreciated.
Vtin, that's interesting. Maybe the Spectral, being wide-bandwidth, presents an uncontrollable load for the Wadia... but why?

The only difference b/ween yr Spectral & other amps is that the former easily goes up to 8Mhz vs. the latters' usual 20-30kHz. I would expect the choice of cables to be critical (I mean electrically) in this case...

Maybe Detlof (who's using Spectral), Sean or others can clarify?
I was running a Wadia 850 direct with a Densen DM-10 Amp. Current passed directly through and blew out my speakers. After sending the 850 back to Wadia (before they moved to Ann Arbor, MI), I learned that the Densen and Spectral are both constructed with similar architectures with wide bandwiths. I subsequently replaced the Densen with a Jeff Rowland, and the problem never reappeared.
Hello Nathanu,

You blew out your speakers (what speakers did you use?) but why send your Wadia back?

Did you blew your tweeters or the bass?
I know you're never supposed to use the spectral power amps with non spectral pre amps. The wadia might be acting like a preamp, sending a signal in to the power amp, but it ain't the "spectral" signal that the amp needs. What do others think about this??
It blew out a woofer on a pair of Aerial 5s. I sent my amp and CD player in for a checkup, not knowing what the problem was.


This following is the email reply from Wadia on this topic:

Thank you for your email message and loyalty to Wadia. I must inform you that the customer, Joe, is correct about the incapability between the Wadia 850 and the Spectral amplifiers. We are uncertain as to why these two components do not work well together, but we have unfortunately found that these units are not compatible. Spectral amplifiers are the only brand of amplifiers that we have found to be incompatible with the Wadia. I hope that this is helpful.

Please let me know if I can be of further assistance at this time.

Best Regards,

Jennifer ZehrGrimm
Sales Coordinator