[Malcyg]

I think the Blue 2 remote might also have control over other Chord gear too. According to the picture in the manual, it doesn't look that different from the remote that came with my DAVE, though I think Chord changed it subsequently.

Just to clarify, are you saying you've found an RCA to BNC adapter at the destination end of a cable is preferable to a BNC to RCA adapter at the source end?

No, that isn't what I'm saying. To clarify, with Dave, I found BNC to be the lowest sound quality input compared with the the other 3. This may be due, in part, to the fact that the player devices were RCA output, like yours. I used a RCA to BNC adapter into Dave initially because I only had RCA cables, but found that many recommended against using adapters of any kind, including Rob himself. I then got a properly terminated cable, RCA one end and BNC at the other and things did definitely improve, but I still favoured the other inputs on Dave. I have not yet tried BNC to BNC cables as I don't any have devices with a BNC output terminal.

 

[Malcyg]

The photo posted by Triode is interesting. By comparison, the remote that came with my Dave is much more of a high end item which also has a learning function and capability to control several other devices. The case is well weighted, rounded and sits very comfortably in the hand as well as having a high end feel to it. It is the best 'supplied with unit' remote that I have encountered. If I can figure out how to add photo's I'll put one in.

Triode - no harm intended, but the remote that came with your Dave looks like you made it yourself in science class by comparison!

 

[Malcyg]

Here you go. Came with my Dave and is better quality than that quick snap implies. A really good remote which I am sure will be able to control my incoming Blu II as well.

 

[Malcyg]

Whilst I've discovered how to insert a photo, here is where my Blu II will be situated. The extravagant looking device on the top shelf is an MBL 1521A CD Transport which is a superbly engineered piece and a fabulous player. I confess that I have my doubts that the little Blu II will sound better, or even as good, but I like Chord and want to try in the hope that the rest of my digital files will benefit from the M Scaler. I should find out soon enough.

 

[Crgreen]

No, that isn't what I'm saying. To clarify, with Dave, I found BNC to be the lowest sound quality input compared with the the other 3. This may be due, in part, to the fact that the player devices were RCA output, like yours. I used a RCA to BNC adapter into Dave initially because I only had RCA cables, but found that many recommended against using adapters of any kind, including Rob himself. I then got a properly terminated cable, RCA one end and BNC at the other and things did definitely improve, but I still favoured the other inputs on Dave. I have not yet tried BNC to BNC cables as I don't any have devices with a BNC output terminal.

My options are limited as there will only be one spare input on the Blu 2 (BNC) and my streamer's digital out is toslink and RCA. Perhaps I'll try an RCA to BNC terminated cable as you suggest. Thanks.

 

[jelt2359]

Just hit stop. The CD can remain in the Blu2.

thanks!

Three other questions :

1) About AES output, it says 'dual' AES. Does it mean that with only one AES output connected the sampling rate is halved? Or are we just not supposed to connect only one AES output?
2) When I use a single BNC output that caps out at 192k for my DAC, are there any downsides to keeping the oversampling rate at 'high' anyway? Or should I bring it down to lower settings?
3) When I output a single BNC and dual BNC at the same time (to two different DACs), do I have to unplug one or the other to make sure the Blu 2 is outputting correctly?

 

[Jawed]

If the delay is 1 mS, then the filter is using 2 mS of data; for the M scaler, it is processing over 1.3 seconds of data, with a delay of 0.65 S. This means that ultra low frequencies is handled in exactly the same way as high frequencies by the filter; I suspect that this is the reason why bass sounds much more accurate, extended, and with much better pitch perception.

Bass frequencies have the highest count of perceptible harmonics - so perhaps it's just accuracy of medium to high frequencies and how they strengthen the perception of the bass? The harmonics are "more harmonic" as it were.

When I used to run active speakers it was quite clear that upgrading the amplifiers on the tweeters (without changing the bass or midrange amplifiers) improved the bass. Yes, the treble was more refined and clearer, but bass percussion and notes became easier to follow, they would sound more powerful, tighter and there'd be a clearer sense of the flow of music, etc.

Going back to the DAVE and DAVE + M Scaler YouTube videos that were linked earlier in the DAVE thread, it was interesting to hear how notes on the double bass had a relatively disjointed feel to them with DAVE: there was the "pluck" sound and then a kind of hole, and then a tail of vagueness, with the pitch of the note being hard to hear. DAVE + M Scaler gave a continuous, joined up sound as the envelope of each note progressed and the pitch of each note was clearer.

I suppose it's worth pointing out that the envelope of a bass note, e.g on a double bass, is probably not the simple shape that the traditional idea of attack, decay, sustain, release alludes to:

http://www.gavinorland.com/tutorials/what-is-an-adsr-envelope/

and so the "wobblyness" of the envelope of many bass notes may be a key thing that a very long FIR reveals.

On the other hand, if WTA or a plain Sinc filter is a pure low pass filter, shouldn't ultra-low frequency content be entirely insensitive to the length of the filter? These filters are flat to 0Hz, aren't they? This would seem to imply that it's solely precision in the filtered result that can affect the perception of bass, which returns me to the idea that bass notes have the most audible harmonics. They have the greatest count of harmonic relationships to screw up.

Now playing: Dire Straits - Telegraph Road

 

[Rob Watts]

Bass frequencies have the highest count of perceptible harmonics - so perhaps it's just accuracy of medium to high frequencies and how they strengthen the perception of the bass? The harmonics are "more harmonic" as it were.

When I used to run active speakers it was quite clear that upgrading the amplifiers on the tweeters (without changing the bass or midrange amplifiers) improved the bass. Yes, the treble was more refined and clearer, but bass percussion and notes became easier to follow, they would sound more powerful, tighter and there'd be a clearer sense of the flow of music, etc.

Going back to the DAVE and DAVE + M Scaler YouTube videos that were linked earlier in the DAVE thread, it was interesting to hear how notes on the double bass had a relatively disjointed feel to them with DAVE: there was the "pluck" sound and then a kind of hole, and then a tail of vagueness, with the pitch of the note being hard to hear. DAVE + M Scaler gave a continuous, joined up sound as the envelope of each note progressed and the pitch of each note was clearer.

I suppose it's worth pointing out that the envelope of a bass note, e.g on a double bass, is probably not the simple shape that the traditional idea of attack, decay, sustain, release alludes to:

http://www.gavinorland.com/tutorials/what-is-an-adsr-envelope/

and so the "wobblyness" of the envelope of many bass notes may be a key thing that a very long FIR reveals.

On the other hand, if WTA or a plain Sinc filter is a pure low pass filter, shouldn't ultra-low frequency content be entirely insensitive to the length of the filter? These filters are flat to 0Hz, aren't they? This would seem to imply that it's solely precision in the filtered result that can affect the perception of bass, which returns me to the idea that bass notes have the most audible harmonics. They have the greatest count of harmonic relationships to screw up.

Now playing: Dire Straits - Telegraph Road

Dial back the clock to 1998-99 when I first started to get the very first WTA filter to work on the DAC 64. When I first heard it, I was struck by the bass sounding very different - it was like you could perceive an extra octave of bass. This was very puzzling at first; but then I remembered my psycho-acoustic studies; the perception of bass in terms of pitch is dependent on the starting transient. The ear/brain is not good at pitch for bass and it infers the pitch from the initial high frequency harmonics. So reconstructing transients accurately would give an improvement to bass perception.

The real surprise was this effect continues with the M scaler over Dave's 164,000 taps; with Dave the time delay is 104 mS (9.6Hz) with the M scaler it is 0.62 S (1.6 Hz) - and you can really perceive the changes in bass performance.

Perhaps the explanation is due to the timing error itself; one of the tests I am doing with Davina is to actually measure the transient timing error directly. IMy thinking is that the timing error has considerable low frequency components that is reduced by increasing the tap length; but this is supposition on my part.

It occurred to me that this transient timing error test could be done using the Blu 2 PCB; so once the Davina decimation filter is coded, I can do this test. It will be very interesting to see if the low frequency transient timing error is significant or not. It's possible that the error of itself is directly confusing the brain, and that is why bass perception varies so much.

Rob.

PS I like to see your now playing! Saw a Hildegard pop up once with the Kronus Quartet, so this gives me something else to get.
Now playing: HILDEGARD VON BINGEN, O Virtus Sapientiae (Kronos Quartet)

 

[Triode User]

Rob,
So, just to be 100% clear and for the avoidance of doubt, if one wishes to have full M scaling when using USB or BNC inputs then the dither switch should be in the up ie off position?

Yes dither toggle (two way switch) should be up (dither off with CD, 1M taps enabled USB and COAX), and the three way switch (sample rate) should be fully down (768 kHz enabled).

Rob, Thanks for replying but I am still not really clear when you would suggest the dither should be on as your reply quoted above implies that the dither switch should be off for CD, USB and COAX ie EVERYTHING. I thought that the dither was intended to be used for 44.1/16 CD playback (as long as no hissing heard)?

Also, whilst I have your attention, the Blu 2 manual says that Blu 2 and connected equipment should be fully switch off before changing any switch positions. Is this required so Blu 2 / Dave can lock on to the new switch outputs or is there some other reason? I'm asking because switching all equipment off is a real phaff.

 

[Rob Watts]

Rob, Thanks for replying but I am still not really clear when you would suggest the dither should be on as your reply quoted above implies that the dither switch should be off for CD, USB and COAX ie EVERYTHING. I thought that the dither was intended to be used for 44.1/16 CD playback (as long as no hissing heard)?

Also, whilst I have your attention, the Blu 2 manual says that Blu 2 and connected equipment should be fully switch off before changing any switch positions. Is this required so Blu 2 / Dave can lock on to the new switch outputs or is there some other reason? I'm asking because switching all equipment off is a real phaff.

Dither is added for CD player only; the feature is only for non-chord DAC's where the addition of dither can make a difference; it is only on Blu 2 because the feature was on Blu 1. I would not do it today. So the dither switch is used to set the video mode filter for USB and the SPDIF inputs, and the video mode setting clearly is not needed for the CD player.

The manual requirement for switching everything off, did not come from me; perhaps it's advice for when not using Chord DAC's. I have always switched whilst on with Dave and Hugo 2 with absolutely no issues at all. Nor can I think of any potential problems either...

 

[Crgreen]

None of that is clear from the manual, which gives the impression that dither should be used for better performance on CD and doesn't distinguish between Chord and non-Chord DACs. Nor can I see anything about video mode filters. Always worth checking with Rob I suppose.

 

[Triode User]

None of that is clear from the manual, which gives the impression that dither should be used for better performance on CD and doesn't distinguish between Chord and non-Chord DACs. Nor can I see anything about video mode filters. Always worth checking with Rob I suppose.

Precisely why I sought clarification.

 

[lovethatsound]

Precisely why I sought clarification.

This is one thing where chord let's itself down . manuals,cables.John,you need to improve this.

 

[birdlandbill]

Over at CA, Romaz initiated a fascinating thread, "A novel way to massively improve the SQ of the SMS-200 and microRendu" that describes a variety of ways to improve SQ, including bridging NAA and router and use of improved clocks, as in the SOtM SMS-200 ultra and tx-USB ultra upstream of the DAC. Romaz has noted improvements in SQ with output from Chord Dave with these upstream elements. Wondering if anyone here using the Chord Blu Mk2 are using any of these and whether a similar SQ improvement is heard? I'm going to be auditioning the Blu Mk2 and Dave in June, but will not be able to assess these features until the Blu Mk2 and Dave land in my home. Thank you.

 

[Crgreen]

I'm not, but in principle, anything which genuinely improves the quality of data via USB to the DAVE should have the same affect into the USB of the Blu 2. I use a PS Audio LANRover (probabaly the only person who is) into the DAVE and it has made a beneficial difference in my set-up. I'm hoping it will do the same with the Blu 2, but I won't know for sure until it arrives.

Out of interest, do you have a link for the discussion?