World's first NOS 24/384 filterless DAC

[PeterSt]

Hi Frank,

.. while the xover math always will be done in the PC (nothing strange here).

Does this mean you configure with crossover processing done before ARC Prediction? (In other 8 channels DAC the PC/MAC is used to programme the crossover software built into the DAC)

Then you talk about stuff like DEQX which is not what I was referring to. So I'm afraid I confused you a bit.

It will be done after Arc Precition, because only then the exact frequencies are known. Arc Prediction is a preprocess, and the xover part will come behind it (like a convolver would).

I want to design and build my own DIY active 2.2 speakers

As in two channel two-way ?

Peter

[Telstar]

It will be done after Arc Precition, because only then the exact frequencies are known. Arc Prediction is a preprocess, and the xover part will come behind it (like a convolver would).

Then it will use a LOT of computing power, unless you can let the DAC do some of the work.

[Nick]

Peter hi,

I have been dipping into the Phasure NOS Dac thread for a while and reading the updates and progress with mounting excitement . Your XX approach carried all the way through to the DAC output has got to be a good thing for listening. I am really interested in a 2 channel model when they become available. I was not sure if your collecting indications of interest / orders, but if you have a list please, please place me on it !

Nick.

[xp9433]

Peter

As in two channel two-way?

Yes, Two channel two-way + (.2) two subwoofers, or it might end up two-channel three-way after suitable experimentation.
Frank

[DannyD]

In anticipation of buying Peter’s DAC, I’ve been trying to get used to using only the volume control in XXHE.  Why?  Because Peter’s DAC won’t have a remote volume control and I’m too used to not having to get off the couch to change the volume.  My current DAC, a Berkeley Alpha, has remote volume and I use a wireless remote connection from my macbook or ipad to control xxhe on my music server.  My listening room doubles as our living room so I don’t want to run wires and have a monitor and keyboard in the listening position.
 
I’m completely frustrated for many reasons:

1) In many listening situations like mine, you fiddle with the volume more frequently than anything else, and interacting with XXHE to do this is cumbersome at best.

2) XXHE is very slow to respond to volume-changes.  My own experience says this is even worse in unattended mode. You’ve missed the phone call before you’ve turned the volume down!

3) Remote Desktop Connection does not work in Windows 7 if you set a core appointment scheme in XXHE.

4) I’ve yet to find a VPN solution, at least for a mac client, that works reliably either.

5) The ipad in many ways is the ideal remote control.  It’s small and light; it runs cool; it has great battery-life.  However, working XXHE’s volume slider and knob takes too much dexterity for a touch-screen interface and the soft keyboard adds too many steps and effort and delay to making what should be a simple volume adjustment.

So why not include a remote control volume with the DAC?  I can’t be the only person who wants one.  Peter says he hasn’t found one that doesn’t damage the sound.  But what about making it defeat-able? That way, purists can use an optimal setting on the DAC and make further volume adjustments on the music server.  For example, on my Berkeley, a setting of 54 is supposedly optimal when you’re using a pre-amp to control volume.  On my 20-year-old EAD, there’s a combination of analog and digital volume: every 6 clicks of the volume switches in a different Vishay resistor and between the 6 clicks adjustments are made in the digital domain.  Obviously, remote volume has been implemented before without a huge sonic penalty.

I don’t think I can justify buying his DAC without remote volume, and from a business perspective, I think his market is significantly reduced without it.  I hope Peter sees the light and figures out a way to provide this very common functionality.  It’s pretty much a show-stopper for me.

How do other people feel? 

[PeterSt]

Hi there Danny,

Not to be ahead of others (so, speakup everybody !), and with the notice your remarks are appreciated at least by me, some remarks to your (in itself valid) topics :

1)
I do too, but far far less with the Normalized Volume active. Do you use it ? you really should ...

2)
I use Unattended Mode exclusively, and the volume changes between 1-2 seconds. Of course you could call that "very slow" (because it is), but is it TOO slow ? not IMO, if you only can trust it "happens". And it can be trusted. As it can at changing the volume 3 times in a row (say 3 presses within 0.5 secs, and the total result will be there within 4 secs). Now it is *this* which can use some improvement, and that improvement is planned : just use the 1,2,3,4 etc. on the Remote to order for 1,2,3,4 steps at a time. Of course at ordering for 4 steps it will be dealt with as 1 (leap of 4).
Will that help you ?

3)
If not solved otherwise, it should be solved "anyway". But notice I don't use any means of remote desktop etc. A normal (but selected MCE) remote will do fine.
Of course, your solution is more versatile, but it will trade that for SQ. Well, theoretically, and I don't even try.
But let's keep it to the "should be solved" for now.

4)
Ditto.

5)
This I can dedicate only to wrong useage.
a. you imply Attended Playback, which is not meant to be in the first place;
b. you should use "remote commands" just the same, never mind you have the option of a desktop in front of you.

But what about making it defeat-able? That way, purists can use an optimal setting on the DAC and make further volume adjustments on the music server.

Maybe I don't get exactly what you want here, but if, say, one resistor would be ok, there would be a fixed resistor volume pot. But even one resistor is not ok.
Of course I realize how difficult it is to grasp, but I gues you must have heard something from the DAC before you are "able" to say something like this.

Obviously, remote volume has been implemented before without a huge sonic penalty.

Haha, how can you tell ? and btw, what is "huge" ?
I go for the best only, and you should too. Suppose I'd give you the volume control, with the prerequisite you are not allowed to listen to women voices anymore. All other is fine, but not that. This is not such a huge minor, is it ?

No, when we talk about minor or huge degradation, we must first have the reference. I have that of course, so again, it will not be easy at all for you to grasp. Not yet.

I hope Peter sees the light and figures out a way to provide this very common functionality.

I saw the light allright. 600 euro for a fine and long lasting LDR volume control, including remote and display. This is for SE output only. Balanced will set you back for more than double.
I have it allright, but can just as well sell it to you (the SE version only). I never even tried it, because the price is ridiculous.

Now, if people could respond to the latter as a nice alternative, I can get a few more so it can go along with the DAC (as an option).
But personally I thought this would be adding way too much to the price of the DAC, and it ain't word sh*t when the digital volume is all so much better.
*If* that operates in a workable fashion ... TRUE !!

?

Peter

[PeterSt]

One thing to add (so you see, it is ALWAYS good to "complain" a little (or more ) :

I must admit that I haven't investigated one situation, while just now suddenly I thought that *additionally* I can bypass it the most easy :

I expect a new, say, construction of the output stage in my mailbox tomorrow, and this is the very final one. But :

The way it is constructed allows me to parallal a 24 fixed (hence step) resistor (Vishay/Dale 0,1%) volume pot, with remote control. The kind of downside is that it "steps" and you will hear that at changing the volume (at low volume). By no way I can predict the result on SQ, because it is not in the signal path, but influences the gain of the output stage anyway. And, because it is not in the signal path, its "being there" can be cut by means of a switch, that switch not being in the signal path either.
Chances even exist that it won't influence SQ at all.

If it works, I think I can apply it for somewhere between 150-200 euro. I must sort that out though.

Peter

[Eric]

For me there is no need to have a volume control capability in the DAC. Any money I need to spend more on the DAcCto have this would be a waste ....for me.
Cheers
Eric

[DannyD]

Peter,

Thanks for the thoughtful responses. 

I do use normalized volume and, yes, it helps a lot.

Can you explain what you mean by using 1,2,3,4 on the Remote? Are you referring to an MCE remote?  Can you recommend one if this is a workable solution?  (I have to add that my experience with the reliability of XXHE’s volume control is not as good as yours.  Less than four seconds? Sometimes it takes a good ten.  Is it affected by Player Priority maybe?)

I’d be interested in the stepped Vishay attenuator you mentioned if it works well.  I’ve used this kind of volume on two conrad-johnson pre-amps I’ve owned. 

Dan

[Telstar]

The way it is constructed allows me to parallal a 24 fixed (hence step) resistor (Vishay/Dale 0,1%) volume pot, with remote control. The kind of downside is that it "steps" and you will hear that at changing the volume (at low volume). By no way I can predict the result on SQ....

24 steps are way too few for me.
But if it works good for SQ, maybe Peter can offer a more fine attenuator.

[PeterSt]

Telstar,

I don't think more than 24 is possible with this concept, but also, it is not necessary. This is a bit in the area Dan talked about :

1. Set a "reference" digital volume (in XXHE);
2. Use the volume within that range;
but also
3. It will reach from maximum output up to some level I have to find out.

Ad 3.
Think something like it can attenuate 24dB, and the 24 steps are available for that range. So, at full attenuation from the pot you still only went 24dB down in effect. #1 above defines the maximum output, which is good for when there's too much gain, altough the pot itself can do that too, when next the digital volume is used (but that is not the subject here, I think).

Don't get too happy, because maybe it doesn't work.

[PeterSt]

Ok, I have worked this out a bit, and there is positive news as well as somewhat negative news.

The negative is that I now realize that this all operates in the differential (balanced) domain, so it takes 4 "channels" of this attenuation, meaning a price of near 400 euro. And no, "differential" means that I can't do only half when you'd want SE output only.

The positive news is that this is relais controlled (no clickclicklcick), and uses 64 steps, for normal operation meant to be 1dB steps. In our application here this means the dB steps will be far less (maybe 1/3dB, but I have to find out what the useable range is).

I just ordered one, but probably everybody will tell me that 400 euro really is too much for a stupid volume control.
Oh well ...

Peter

[Telstar]

Ok, I have worked this out a bit, and there is positive news as well as somewhat negative news.

The negative is that I now realize that this all operates in the differential (balanced) domain, so it takes 4 "channels" of this attenuation, meaning a price of near 400 euro. And no, "differential" means that I can't do only half when you'd want SE output only.

The positive news is that this is relais controlled (no clickclicklcick), and uses 64 steps, for normal operation meant to be 1dB steps. In our application here this means the dB steps will be far less (maybe 1/3dB, but I have to find out what the useable range is).

I just ordered one, but probably everybody will tell me that 400 euro really is too much for a stupid volume control.
Oh well ...

Peter

When I said 24 steps are too few, i was thinking about full output and each step of 1db each which is too coarse for me.
But this way, 0,5db or less, and setting a reference volume in xxhe (maybe or maybe not for highres files), it would work for me, very well indeed.

I have a question, though: will it work with 8 channels? I can have all balanced outputs for what i care of that ^^
The most important thing is that all steps have the same impedance output seen by the amp (which IS different than without it).
400 euro is fine by me - any decent pre costs more. The savings on cables alone is very much worth it.

I'm really happy of this news.

[DannyD]

I just ordered one, but probably everybody will tell me that 400 euro really is too much for a stupid volume control.
Oh well ...

Peter

I agree.  400 euros is a lot.  I'm just a 2-channel, balanced listener.  But if it works best...

First I'd like to try the MCE remote approach.  I’ve spent the last few hours looking for one, and all I’ve seen are not programmable but learn-able where you need another working remote to teach them the codes.  I need to be able to program them with Alt-N, Alt-U, Alt-D, etc.  Also, the ones I’ve found don’t come with a USB IR, which I need to plug into my PC. 

Does anyone have a good remote/IR receiver to work with XXHE?

[PeterSt]

Dan, look here for a Remote : A Working Remote.