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Any comments on DAC going direct to power amplifier or to pre-ampliifer?

My local retailer HIGHLY RECOMMENDS the use of a pre-amplifier.  Bricasti believes that going direct to a power amplifier sounds better.  And, I also know that everyone had a "different opinion" about going direct or using a pre-amplifier.  

I am running my Bricast1 M1 SE DAC direct to my Hypex NCore NC400 Bridged Mono Block class D power amplifiers (no pre-amplifier) and like the sound quality very much.   

For me, the sound is more natural and clearer by going direct to a power amplifier. Of course, I think the M1 SE DAC has special “custom" circuits in the analog section to make it sound so good. I returned home and listened to my system.  It sounds terrific and I continue to enjoy and recommend the Bricasti M1 SE DAC.

Please note that we removed the R141 (circuit) from my Hypex NCore NC400 bridged mono blocks, thus lowering amplifier gain by 14 dB, requiring 14 dB higher M1 volume setting for same playback level.  Bricasti says the goal is to have the M1 CLOSE to 0db front panel attenuation.  If you reduce the volume on the M1 SE DAC, you cause more bit reduction meaning you lose sound quality.   We discussed this modification with Hypex and they approved the removal of the R141 circuit.  They suggested we be very careful removing the 4 R141 chips (for my 4 NC400 amplifiers) to avoid board damage.  

I noticed that many of the newer DAC’s (even the new Ayre QX-5 Twenty DAC and many others) have volume controls meaning their DAC/Pre-amplifiers are designed to go direct to a power amplifier (as an option, of course).  

What are your experiences of going direct to a power amplifier or using a pre-amplifier?  Have you compared going direct vs. going to a pre-amplfier and noticed any sound quality differences?  Have you gotten different results from using different DAC's and amplifiers?   Your comments are appreciated.  Thanks.





hgeifman

Showing 2 responses by hgeifman

hgeifman OP
2,113 posts
 
George:  Thanks for your suggestions. As I stated above, we removed the R141 circuit from my Hypex NCore NC400 bridged mono blocks, thus lowering gain by 14 dB, requiring 14 dB higher M1 volume setting for same playback level.  This allows me to increase the volume control on my Bricasti M1 DAC to a higher level as you recommended.  Changing the gain levels on the Bricasti M1 DAC requires a volt meter (?) to manually balance the gain between the left and right channels. If any one is interested in doing this, please contact Bricasti for the details.  

tls49:   You answered my question.  After thinking about it, I agree that the components used, the environment of the room and the listener’s preferences will impact the decision of the DAC going direct to a power amplifer or going to a pre-amplifier.  As you said, there is no correct answer because of these many variables. In my case, I prefer going direct to my power amplifiers. Thanks for your simple and great explanation.  


hgeifman OP
2,113 posts
 
Okay.  I changed my mind about having my DAC going direct to my power amp. The volume control in most DAC's (including my DAC) is indeed implemented in the digital domain and, therefore, when adjusted down, bits are lost AND so is the sound quality. This is a fact of digital volume controls. In other words, reducing a DAC's volume causes bits to be dropped resulting in reduced sound quality.

As an experiment, I discovered that my 2nd DAC sounded better than my first DAC both going direct to my power amplifier. My assumption is DAC #1 was dropping more digital bits then DAC #2 causing the sound quality differences. Based on this experiment, I am now considering using a pre-amp.

I also continue to believe that everyone has a different opinion on going either direct to a power amplifier or using a pre-amplifier. I believe these differences are because we all hear differently and different equipment sounds different in different conditions. Some DAC's may drop bits in different increments (I do not know). 

I plan on adding a preamp/DAC to my audio system shortly.  
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