CHORD ELECTRONICS DAVE

[Rob Watts]

  After reading the manual the only thing that bothers me about DAVE's operation is having to manually select either the PCM+ or DSD+ filter to optimize PCM or DSD playback respectively. It would have been nice if there was an automatic mode option where it would switch based upon the type of digital file being played, but maybe that wasn't possible since it has to reload the software which apparently takes about 20 seconds to complete. I also didn't see any mention of whether DSD has to be input as DoP or if it accepts the DSD bitstream directly.

Believe me I tried - spent about a month trying to make it seamless - but it had to be click free and not capable of triggering DC protection in DC coupled power amps, and have a digital DC servo that was inaudible in operation with no change in SQ. This was the only way of making that happen.
 
DSD is DoP or "native" mode using ASIO - indeed for DSD 512 native is the only way.  
 
Rob

 

[audiobill]

Thanks very much for your reply Rob, your efforts and candor are very much appreciated!

 

[rkt31]

gone through the manual. the manual clearly explains everything. that hf filter was not mentioned anywhere in the previous discussions here. can anybody explains what exactly the hf filter  does and how ?

 

[Rob Watts]

The HF filter is a sharp cutoff filter set to 60 kHz. The intention was to bandwidth limit high sample rate recordings - DXD and 384k have huge amounts of noise shaper noise from the ADC. This noise will degrade SQ by increasing noise floor modulation as the out of band noise creates intermodulation distortion with the wanted audio signal in the analogue electronics.
 
Now it works very well, in using it makes it sound smoother and darker - exactly what you get from lower noise floor modulation. But the curious thing is that it also sounds better with 44.1 k - curious because the WTA filter typically has a stop band attenuation of 140 dB (worst case 120 dB). So out of band noise is very low with 44.1 k and I was not expecting a SQ change with the filter with CD. The filter is not something added, its just a different set of coefficients for the 16 FS to 256 FS WTA filter.
 
Something else to look into in the future as this suggests that 140 dB (typical) stop band attenuation is not enough.
 
Rob

 

[rkt31]

thanks Rob for the quick elaborate response !

 

[DaveRedRef-III]

Thanks for the HF filter explanation Rob. My experience with Dave confirms your conclusion. It does sound better to me with the filter on and I only use Redbook currently. I wondered if it was having an effect on the electrics because when turned on the sound is warmer and more natural.

 

[DaveRedRef-III]

Beolab
The HF filter does sound better to me, so I leave it on.

As mentioned earlier on the thread I do not listen via headphones. Sorry.

I do not have a generator. I use an Isotek synchro for hum, an Isotek Sigmas for Common and Differential mode and RFI noise. I also use Vertex AQ's which work passively to suppress RFI. I have yet to take the Sigmas out of the chain to see if it is actually necessary. I want to get used to the sound first and until yesterday it was still changing due to burn-in.

 

[TheAttorney]

What was the rationale for providing a surprisingly generous 4 BNC inputs, but no RCA?
Even if BNC is considered the superior connector, surely one of the 4 could have been replaced by RCA, if only for convenience or comparative purposes?
 
I raise this because my Nagra CD player has only RCA, XLR or optical digital outputs, and the RCA (connected to Yggy) gave a significantly better sound than XLR - against all my expectations.
If it had BNC I'd use it, but it doesn't, so I can't..   

 

[Mavwong]

Isotek Aquarious already pretty good but you have sigma!
 
I am intended to get a sigma demo unit in my system as well.
 
 
 
Quote:

Beolab
The HF filter does sound better to me, so I leave it on.

As mentioned earlier on the thread I do not listen via headphones. Sorry.

I do not have a generator. I use an Isotek synchro for hum, an Isotek Sigmas for Common and Differential mode and RFI noise. I also use Vertex AQ's which work passively to suppress RFI. I have yet to take the Sigmas out of the chain to see if it is actually necessary. I want to get used to the sound first and until yesterday it was still changing due to burn-in.

 

[Beolab]

Would be very inresting to hear som impressions based on the cross-feed filtering , wich one is to prefer, or is it just set it to off like in the Hugo?

 

[lovethatsound]

Beolab
The HF filter does sound better to me, so I leave it on.

As mentioned earlier on the thread I do not listen via headphones. Sorry.

I do not have a generator. I use an Isotek synchro for hum, an Isotek Sigmas for Common and Differential mode and RFI noise. I also use Vertex AQ's which work passively to suppress RFI. I have yet to take the Sigmas out of the chain to see if it is actually necessary. I want to get used to the sound first and until yesterday it was still changing due to burn-in.

Hi Dave
Could you tell me what cable you are using from your cd player to the Dave dac,or have you tried different cables?if so which one do you prefer?

 

[Beolab]

HiFi Lounge have not spend so much on power cables, but i think it sounds good nevertheless

 

[PANURUS]

I heard the Dave in a demo show. The first day 8 hours and the next days 3 hours.
 
My conclusion after 5 minutes: I will have one in June.
 
With Dave I can hear what the singer visualises when he vocalises the word.
 
The intension that he put in a sentence is more clear.
I understand the text like he sees it.
I hear if he is sad or ironic or if he is just producing sounds.
 
I hear the Dave with STAX SRS3170 and  Wireworld silver eliptic 450euro/m  and Gold 1800euro/m.
With the Gold cable, it's magic. With the silver eliptic, good for 450 Euro.
And the quality of this first price Stax is uncredible.
 
But in each case, the most benefice of the Dave is on Voices.

 

[musicday]

Panurus,have you tried any other headphones with Dave other them PM3?
Thanks for your words.

 

[PhilW]

I just wish I had a demo unit. All of the DAVEs we have received have all been client's units.