Smooth DAC with XLR cables stop ear-bleed.

rskarvan

Here is a mini-review of my system....

Speakers are 3.1TL SDA's.
I originally drove these form a Denon 3801 (105wpc). Not enough power to make them sound good.

I splurged and purchased a used Krell KAV 250A (250wpc). Now, lots of power. I used the Denon3801 as a preamp and that worked fine.

Then, I decided to get a Krell preamp with home-theatre pass-thru. Honestly, the Krell preamp didn't make all that much difference.

I hooked up the preamp to the amp using an XLR cable (balanced connection).

The system was fine... but, not incredible. Just fiine.

On a whim, I purchased a balanced ADCOM DAC (GDA-700). Now, I have a balanced DAC feeding a balanced pre-amp, feeding a balanced amp, feeding my 3.1TL SDA's.

WOW ! ! ! The balanced source made an incredible difference. The whole system woke up and took notice. Dynamics are much, much better. I am now hearing HDCD for the first time... and, it greatly improves the sound of CD's. The DAC is smooth. Not exceptionally detailed. But, smooth. It tamed the metallic sound of the tri-lams on the SDA TL's. I can listen to my entire cd collection without getting that worn-out feeling that my ears used to experience.

My old cd player was a very respectible older JVC single-bit player. I never realized how harsh that cd player was until I heard the ADCOM DAC.

I think the balanced connections makes a lot of difference. There is some synergy between the DAC, PREAMP, AND AMP that I didn't experience until I got all three hooked up with XLR connections.

The XLR cables I purchased off e-bay are Monster 1000i's. The two sets of Monster 1000i's MSRP for $500. I think guys are nuts to spend that much on cables. I got them off e-bay for about $40/set and I'm can deal with that kind of coinage for interconnects.

I've never heard my SDA's sound so pleasing to the ear. The difference is the DAC and the balanced XLR connections throughout.

One more thing, the XLR connection of the DAC boosted the output of my Krell amp CONSIDERABLY. I used to turn the preamp half way to really listen loudly. Now, with the XLR connection, I get even more volume at about 1/4 the way up. I don't quite understand that... but, it makes my KAV 250A sound like a beast of an amp (and, I suppose it really is - but, I never really noticed it before). Before, I just thought it was a rather big box for an amp.

All three pieces of the source were purchased used at less than 50% of MSRP and have worked flawlessly. If you want to be an audiophile and you have a budget.... my recommendation would be to go for quality on a shoe-string budget.

Thanks for listening.

audiobliss

Nice little write-up. Interesting to read what you think the XLR cables are doing for you. Krell is some nice stuff, for sure. Less than 50% MSRP for all three pieces...cool!

heiney9

Congrats on finally entering the realm of seperates. The XLR connection certainly is worthwhile and does give you some sonic improvement. The DAC is what is giving you the most sonic nirvana at this point. With respect, that JVC regardless of age was never a top performer. You have a totally kick a** system now with Krell, SDA's and a top performing DAC....I bet life is good, enjoy! Isn't it great when things like this come together

H9

steveinaz

I've noticed that my CEC transport sounds better via XLR digital IC instead of coax into my Benchmark DAC. The XLR is a Signal Cable product, the Coax is the DH Labs DH-75. The XLR really smoothes the treble very nicely.

organ

Excellent review and congrats on the new system. Aren't those tri-lams awesome once you find the right gear for them? I miss my 800i's.

Maurice

Schris22

Congrats on reaching your high!

Chris

rskarvan

FYI -- I asked Krell about the louder XLR connections.... this is what they wrote back.

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Dear Ron,

Thanks for your communication. Believe it or not this is not a problem. Every truly balanced (XLR) connection that you add to a system adds an additional 6 db of gain to the overall volume level. This is (usually) one of the three advantages of operating in balanced: 1- its a better sounding circuit in general overall over that of a single-ended design, 2 - you get a lower noise floor - meaning you hear more of the music and less noise, and 3 - you get an additional 6 db of gain.

The above now said, in some systems circumstances more gain may not exactly be a good thing, especially if you are in a very small room. However keep in mind that one of the advantages of the KAV-250P is that it does not use a real volume potentiometer. It uses a digital encoder in conjunction with resistor (ladder) network instead. Meaning that its sonic capability does not depend on your having to turn the volume up louder in order to try to get by the resistive (negative) sonic characteristics that a normal volume pot brings to the table.

One last thing to keep in mind. A standard source components (AKA: CD player, DVD player, Tuner etc) singled ended (RCA) analog output signal level is 2 volts. The same analog output signal but in balanced doubles, making it a 4 volt signal. A 4 volt balanced source signal going into almost any preamp is going to make a pretty big difference in your overall system gain level. If by chance the Adcom unit is outputting more than 2 volts in single ended then this gain difference in balanced will be even more dramatic. Meaning you might want to look in your manual and or call Adcom and find out the specific analog output voltage of this unit in both single ended and balanced. That now said, if you are not experiencing any distortion and basically the system is simply playing louder but with less volume control adjustment, meaning technically there is not a problem, as they say "if it ain't broke then don't fix it".

regards,
Patrick Bresnahan
Service Manager
Krell Audio

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From: RonSkarvan@aol.com [mailto:RonSkarvan@aol.com]
Sent: Tuesday, October 25, 2005 6:28 PM
To: ServiceMailbox
Subject: Preamp XLR-INPUT Question


Hello.

I have a general question about my Krell equipment.
I have a Krell KAV 250 P pre-amp and a Krell KAV 250 A amplifier.
I have always run my pre-amp to my amp using XLR cables without any issues.

Recently, I purchased an Adcom GDA-700 balanced (XLR output) DAC.
I hooked up the XLR cable from the DAC to the KAV 250 P and the output is louder than I am accustomed to hearing. With single ended input from the ADCOM DAC, things are more normal (to me) volume-wise.

The question I have is that the "loudness" of the DAC via the XLR cables thru the preamp is much, much louder than I have heard using single-ended connections.

The sound is fine (very clear, crisp, etc). But, I can't turn it up past two lights without getting overwhelmed by volume. Also, the KAV 250 P doesn't really allow me to finely adjust the volume on the low end.

The KAV 250 P has always been just fine with single-ended inputs.
But, these XLR cables from the DAC to the pre-amp cause a substantial (almost scary) volume boost.

Is this normal? I'm listening to speakers that are rated at 87 Db efficiency (8-ohm nominal).
If you could answer with a brief technical description of why this is happening, I would appreciate your response.

Thanks.

Ron Skarvan

audiobliss

Wow. What a personal, detailed, informative reply. How long did it take him to reply? Another company with great customer service!!

rskarvan

Krell replied to me in one business day. They do offer very impressive customer service. My remote died and they replaced it for free with an upgraded one - no questions asked. In my opinion, expensive, but done right and worth it.