When it is placed closest to the primary offenders (emanating vibrations) in the unit, they work best.
The digital box will run cool, you can stack on it or have a small air gap. The analog box will be warm, Iād not stack on it and Iād leave, say, 2" free above it?
I didnāt mean to imply that they were TOSLink cables. They are POF, see the link a few posts up. Youāll be able to buy POF where ever you want, but it typically comes in 100m or 500m rolls 
I bought a prebuilt POF cable and cut the ends off. You need to use the provided cutting tool and itās only good for two cuts (one on each end of the cable to square things up.) Iām sure PS Audio will offer some precut cables and probably a kit with a long cable and a cutter.
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@tedsmith - thanks Ted, yeah, 9.5in shelf on the analog and 7.5in shelf on the digital. Will use the cutting tool and assume there the community will be weighing in as to the best practice on the cable cuttingā¦ yeah, just saw the video on POF cable, looks really easyā¦
This is a really interesting discussion. I think PS Audio is unique in that it permits an audiophile to follow the development of a new product, including the rationale by the developer for the choices he made and what he expects of his decisions.
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Yet another question for you, Ted, if you have the time and inclination.
Iām one of those seeking the best possible sound in the simplest possible system, which means I want my DAC connected directly to my power amp to sound as good as or better than having a pre-amp in between them. I understand the challenge of sensitivity and how the DS DAC attenuator relates to that. I also understand something about the challenge of the DACās output being able to drive the amplifierās input and how that relates to impedances.
My question is whether you have considered using multiple output windings on the DACās audio transformer, and switching between those, as opposed to a single output winding with switchable shunts for reducing level (which is what the DS does today and the TSS is said to do in future).
The question comes from my reading about the value of TVCs and autoformers, wherein a reduction in voltage also means a reduction in output impedance and an increase in drive capability. That sounds more desirable than a shunt which doesnāt help on the impedance front.
In my case, I would be pretty happy with about a -10dB level reduction from the DS full signal, which would be whatā¦ -16dB from the TSS? Given the additional output switches that the TSS has Iām guessing itāll have better drive than the DS anyway, but the idea of even further lowering impedance via the transformer is appealing.
Asking solely out of curiosity and enthusiasm. Iāll be taking a serious look at the TSS regardless.
PS Audio and I actually got a custom transformer with the 20dB attenuator built in, and, well, it sucked. Getting a custom transformer of the quality of the transformers we are going to use would cost a heck of a lot.
Consumer audio gear almost exclusively uses a low impedance output into a high impedance input, but no matter what the source impedance (within reason) the impedance at the input of the (pre)amp sets the current draw at any given voltage. Having either a 120 Ohm source or a 2 Ohm source driving a 47k Ohm input impedance amp doesnāt change the current down the interconnects hardly at all.
The key to lowering sensitivity to current noise is to have a load right at the input to the amp. You can test this by putting a 1k (or whatever) resistor at the input to your amp. That will draw more current from the DS and give you a better current S/N over the interconnects. Whether you would hear it or not I donāt know. If your system is sensitive enough you could put, say, a 30 Ohm resistor at the amp input and with the DS youād have about a 20dB lower level but a lot more current. I suspect that youād hear the improvement in many systems. (This probably wonāt work with most sources, but the DS is comfortable driving a dead short.)
[Edit: I should have mentioned that balanced interconnects eliminate common mode current noise better - but the curious might try the resistor.]
The TSS will have -10dB, -20dB and -30dB attenuation options and for unbalanced cables a +6dB option.
[Edit 2: And the TSS will have the āstandardā CD/SACD player levels which is 3dB higher than the DS and DS Jr.]
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Really appreciate the response as always, Ted.
Itās cool to hear you looked into the custom transformer option. Am I right in interpreting that ā20dB attenuatorā as being an additional winding? Not surprised to hear that they were expensive, though it is a shame.
Without wanting to derail into the pre-amp vs direct debate, I canāt help but think that what you wrote tends to align with the āhaving no pre-amp is a technically better option provided impedance and gain are suitableā argument, and that could seem to conflict with comments from both Paul and yourself to the effect that itās generally better to use a pre-amp than to not. Ultimately Iām trying to have my cake and eat it tooā¦ if a pre-amp sounds better I want to know why, and I want to get the absolute simplest possible version of that. I donāt need multiple inputs, I donāt need more gain, I donāt need better quality attenuation than what the FPGA gives me. Iām hoping that the most ācorrectā reproduction is the best-sounding reproduction, which has seemed to be the way of things in my audio journey to date.
BTW Iām running balanced interconnects from the DS to a fully balanced/differential power amp. Can resistors at the amp end be used in this scenario?
Yes, but just one resistor across the two differential lines, not two resistors, one from each line to the ground. I have no idea if it would help in a given scenario, but it would be a good experiment to try in a few different systems and see what it does, if anything. Iām sure it would help in a lot of unbalanced situations. But in a well implemented balanced setup it shouldnāt make as much of a difference.
A preamp can help in other ways than just input selection, volume control and potentially buffering. It might react to ultrasonic noise better than the amps, for example filtering it out when otherwise the amp might not be linear which could modulate it down into the audio band.
Like all things using preamp or not depends on the quality and synergy of the various system components.
In my situation I canāt run without a preamp - itās critical to be able to control the level carefully in the presence of bugs
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" [Sep '18] Ted, your knowledge seems to be limitless. Always fascinating reading your explanationsā¦"
Canāt agree with you more @Dirk on your above comment. It is like firehose of knowledge. Though I cannot follow all of his musings (because of my ignorance), I still read them fully with the hope to gather as much as my untrained brain can. One of the reasons, I feel emotionally so connected with my DS Dac (I was one of the first persons to pre order it back in March/Apr 2014) is Ted.
@tedsmith Ted I wonāt be able to afford TSS (and I luv my DS and DMp combo very much) but surely wish you all the best and a great spectacular success with TSS. I sincerely think hi fi world needs many more technologists like you (and surely also patron like Paul @Paul).
Regards,
Sourav
Maybe a prize should be on offer for anybody who can ask @tedsmith a technical question that he doesnāt know the answer to.
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How is this coming along MR. Smith? Release date?
Per the above I think MR. Smith is probably the most knowledgeable and innovative Engineer currently on the planet! I cannot wait for this. I really hope it does slaughter my loaded Select DAC II with Mono Power Bases.
Me too. Then you can sell your MSB to me.
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No idea on release date: ASAP sounds good to me. I am enjoying listening to it, but there are still bugs that none of you want to be subject to.
Right now the focus is on finding hardware issues and testing fixes for them, then I can start refining software and see what it can really sound like. I do enjoy listening to it more than the DS, there are obvious improvements in the bass, blacker background and ease. And tho Iām happy to listen to the DS or DS Jr for any period of time, the TSS still seems to cause less fatigue even when played at higher volumes - Iām sure partially due to both less ultrasonic noise and cleaner sound with less low level distortion.
Donāt ask for more sound quality info - thatās changing day by day and Iām really working on function at the moment.
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Finished the first 90 % and now for the second 90 % 
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It sure feels that way at times
In a previous company we called it āthe law of perspective: the closer it is the bigger it looksā
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Remembering Tedās understatement talking about Snowmass something like ānot sure if the sound effects will be audible for everyoneā, it seems that āI enjoyed listening to the TSSā is a never experienced listing adventure to be expected! 
We have to learn to read Tedā¦
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Iām with you on this one. 
The press release pre-AXPONA gives a better idea of the price range, and I guess this is where I opt out (with distributor premium, will be at least 3M JPY in Japan).
I will probably live without an upgrade for a while until there is either a successor to the DS DAC (or a one box TSS light)
I have to say the boxes look nice in the video from the show, better than what I expected.
I too use a DS Sr. without a Bridge. I use a Sonore Signature Rendu SE as a Roon endpoint, USB to the DS.
I have no intention of changing that setup if I donāt have to as it is excellent.
I donāt use the volume control on the DS as my setup uses a pre-amp (even though I only have a single input, the DS) because it sounds better than running the DS direct to the amp. If the TSS (or Obsidian as it is known now) sounds as good without a pre-amp as with one then that would be a deciding factor for me purchasing it.
So for me, invest in eliminating the need for a pre-amp first and foremost.