Was Upcoming DS release - Now Windom has been released

Has anyone noticed that the Stellar Gain Cell DAC has three user filter settings as do many DACs such as Chord, iFi Pro iDSD and others. Yet the DirectStream DACs, both Jr. and Sr. have no user filter settings.

The same user filter settings in Stellar Gain Cell DAC would be a much appreciated upgrade for the DirectStream DACs for the same reasons they are incorporated in the Stellar Gain Cell DAC which is described on the PS Audio website as “each filter can be selected and auditioned by the user to more perfectly match their chosen collection of the amplifier, source, and loudspeaker, as well as personal tastes and biases.”

Those that use computer sources running Roon or Audirvana have the advantage of software user filter settings, but for a CD player, PerfectWave Transport, DirectSteam Memory Player, NAS, Tidal, Qobuz to Bridge II, or a music/media server as sources to the DirectStream DACs, no user filter settings are available.

Since the filters are already setup in the Stellar Gain Cell DAC, a less expensive DAC, one would think it would also be possible through a firmware update to add those same user filters settings to the DirectStream DACs. There is a button on the remote labeled “SR”, which currently seems to have no function, that could be used to cycle through the user filter settings. Or the user filters settings could be accessed on the touch screen. The least favorite option would be offering different firmware update choices, i.e. Mountaintop F1, Mountaintop F2, Mountaintop F3, where “F” represents a specific filter, but at least the user filter choices would still be available to DirectStream DAC owners.

Here’s hoping that PS Audio will give this suggestion some serious consideration.

The filters are part of the DAC chipset’s software. The Directstream’s don’t use a standard chipset like the SGCD does.


or rather you’re choosing the ‘filter’ by choosing one release or another i.e. Redcloud or Snowmass


My understanding is that such filter settings would inherently be superfluous in light of Teds FPGA (did I get that acronym correct?) approach to filtering analogue from the digital, so to speak. Hopefully, @tedsmith will chime in and correct any ignorance I have displayed/elaborate.


The Stellar Gain Cell DAC user selectable audio filter settings are 1) Slow Roll-off Linear Phase, 2) Fast Roll-off Minimum Phase, and 3) Fast Roll-off Linear Phase. The user has the ability to choose an audio filter to best fit the user’s preferences for the user’s audio system and ears. Many other DACs now also offer filter choices for users. The DirectStream DACs have no user selectable choices for such audio filters, but it seems reasonable that the audio filter choices could be added and would be a great enhancement to this DAC as they are to the Stellar Gain Cell DAC.

The filters are part of the ESS Sabre chipset software. They are available for every DAC that uses an ESS Sabre DAC chipset. Some manufacturers activate them and some don’t. Again this is not possible with Directstream DAC as their is no chipset so no filters.

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Just what we need…Ted spending valuable time and brain power contemplating, coding, and implementing additional filters for the DirectStream.

Ted’s code is already great. If you want different filters, get HQPlayer and integrate it with your setup. No, it won’t work with transports. But, you can always rip your CDs and SACDs and play them via some software setup.


In the current code the PCM upsampling filter takes about 1 / 4 of all block memory, there’s not enough room for more good quality filters.

The filters in question are usually different upsampling filters: if I only changed the PCM upsampling filters the DSD would be essentially unaffected: generating the effects of a rolled off filter around 22k in DSD would be one thing, but what’s a minimum phase filter at 5MHz supposed to do?

Waiting for a DAC reboot when going from one mountain top to another would probably be annoying, but more importantly there’s no room for more than about 1 1/2 mountain tops in the current systems: we shoehorned the FPGA code into some unused graphics memory in the PWD.

One of the really annoying consequences of having multiple filters is that I’d have to try to have every new release keep the characteristics of each original filter. When we’ve let more than one version of a given release out people express strong feelings for each of the various versions, there is no way (not an exaggeration) to keep these minor characteristics consistent from one release to the next.

I personally don’t have any interest in developing filters that I don’t believe in: just having sloppier filters available for the express purpose of having sloppier filters would annoy me. For example take “rolling off the top end”: why? use a bad or high capacitance cable. Minimum phase: Destroy the wave shape of the signal on purpose? Muffle the transients? Why?

To be honest I can use the time, effort, FPGA resources more effectively for better overall sound.


@tedsmith - Ted - thank you, very well put, the reason we love the way you prioritize your time. Thanks for answering that the Ted way - right to the point. If I wanted to buy a canned DAC with canned filters, I would not have purchased your magic and would have slid off the mountains…


I should have prefaced my answer with something like:

That’s a good question and I’m sort of surprised it hasn’t come up more often.

I was a little worried about having to do multiple quality filters in the beginning, but with every release the message was clearer: do the best you can technically and you’ll get the best sound: that definitely applies to filters.


@tedsmith - Ted getting all PC on us… anyway, great answer… both of them…

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I just don’t want people to feel picked on. I meant everything I said in both posts.

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@tedsmith - yeah, I didn’t take it that way and I assume others did not. You’re just pointing out factually your approach is different and your loyal customers want better technical, not adding filters. They have their place and all good, just want to stay pure… when is the next mountaintop? OCT?

We’re jonesing for a fix Ted… Snowmass was BAM! @Paul was talking up the next mountain. We need to name that mountain… have you thought about the name yet?

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Thanks for the chuckle, Ted. People are starting to get scary around here.


You know, I often ask myself that very same question…I’m losing sleep with that thought swirling around in my head all the time :face_with_hand_over_mouth:


75 posts were split to a new topic: Naming Silliness

So I got my new SD card yesterday. :slight_smile:

And what was on it?

Mt.Sneffels ? :thinking::grin:

How about this…

Snaefell Mountain - Isle of Man
For those who also love motorcycles and racing.

Wrong country and state, I know, but still…