New: Hang Loose DSP Processor

[Keith_W]

@mitchco has been hinting that this unit has been in development for some time. It appears that he sneaked an announcement into his webpage without much publicity: link.

At the moment, details are very scarce.

These are my speculations based on the ports at the back of the unit:

- 2ch, 8ch, and 16ch versions will be available (2ch version shown) - as announced on his webpage.
- Includes Hang Loose DSP Suite + some other plugins
- FOUR LAN ports. Why so many LAN ports? I am hoping that the answer is "Dante/Ravenna/AES67 compatible" ... but we'll see!
- 5 USB ports and 4 HDMI ports. This configuration makes me guess that there is an x86 or ARM PC inside. However, lack of cooling slots or fins suggests that it won't be x86. It also makes me wonder if there is an on-board HDMI decoder, which means that this thing can potentially be used as a substitute for an AVR.
- Mic input. This suggests you can use this unit to take measurements with an XLR mic, a separate interface is not needed.
- Given Mitch's previous positions on FIR vs. IIR, I think there is a very strong likelihood that this is a FIR DSP unit. Also, the inclusion of the HLC DSP suite suggests that you can use any software you want to generate FIR filters (not like a certain competitor who have not only priced themselves out of the market, but ALSO require cloud-based processing using proprietary software).

I am excited about this unit and I can't wait to see what else he announces - notably, price.

 

[Bjorn]

Trigger seems to be missing.

 

[Bjorn]

With the looks, it clearly looks aimed at the professional market. That's unfortunate IMO to only focus on that market. Sure, DIY people who generally don't care about aesthetics will also buy it. But for the general audio home market, the looks of the unit is terrible.

 

[Keith_W]

Hmm, to be honest I didn't think about the looks until you mentioned it. I like it, it's functional, and I think the indicator bars at the front of the unit are an essential feature. If anything, I want more indicator bars, but I can see how it would be a turn-off for some people. Maybe you could do what Kyron Audio did with DEQX - when they collaborated, they essentially put a DEQX into a fancy case and sold it for umpteen thousands of dollars. Or what Merging did with the NADAC - essentially a Hapi in a fancy case but with fewer features.

As for the 12V trigger ... maybe it has Wake-On-LAN. We'll have to see.

 

[dualazmak]

- 2ch, 8ch, and 16ch versions will be available (2ch version shown) - as announced on his webpage.

If it would be so, I am very much interested and excitedly looking forward to seeing them, as you know well about my multichannel audio rig...

Spoiler

Furthermore, I wrote here;
USB 16-Ch ASIO input (by one or two USB 2.0 cable from PC) and 16-Ch balanced analog out should be just enough for me. Therefore, my simple wish for 16-Ch Sync Pro DAC, (OKTO?) DAC16PRO(?) with two (or three?) of ES9028PRO or ES9038PRO (or new AKM DAC chips?) in it; 8-Ch AES/EBU stereo inputs would be welcome for future possible use, and for those who in pro field...

Of course, the dedicated ASIO driver in PC should recognize all of the 16-Ch of this gear; quite easy to be achieved, I believe.

I do hope Pavel of OKTO would look here.

 

[dualazmak]

No analog balanced "outputs"???

Spoiler

When I went into audio enjoyment hobby-world in my young era, my audio-advisory guy, who was in pro-audio world, taught me in non-elegant wordings;
"You need to remember in this way. Male XLR should only output/ejaculate signals, Female XLR should only accept the signals, in any setup of audio gears."

 

[Keith_W]

No analog balanced "outputs"???

Spoiler

When I went into audio enjoyment hobby-world in my young era, my audio-advisory guy, who was in pro-audio world, taught me in non-elegant wordings;
"You need to remember in this way. Male XLR should only output/ejaculate signals, Female XLR should only accept the signals, in any setup of audio gears."

I think we should wait for more information from Mitch.

 

[welwynnick]

- Given Mitch's previous positions on FIR vs. IIR, I think there is a very strong likelihood that this is a FIR DSP unit. Also, the inclusion of the HLC DSP suite suggests that you can use any software you want to generate FIR filters (not like a certain competitor who have not only priced themselves out of the market, but ALSO require cloud-based processing using proprietary software).
I am excited about this unit and I can't wait to see what else he announces - notably, price.

Yes, I'm standing in line, too. My interest would be in the 16 Ch version, that might be used with an Arvus, Audiopraise, Hyperion, or Nuprime, for example.
I guess the HLP takes the digital audio output from a transport or a decoder, performs Hang Loose Convolution, then outputs digital audio to a DA converter.
Therefore it takes the place a PC running HLC, which would be a good thing, but doesn't do decoding or conversion.
However, that doesn't explain the existence of the HDMI connections, which suggests there's potential for some Dolby / Atmos decoding, which is a whole different ball game.

I'm curious about "Mitch's previous positions on FIR vs. IIR"? I'm not aware of that - could you elaborate?

Cheers, Nick

 

[Keith_W]

I'm curious about "Mitch's previous positions on FIR vs. IIR"? I'm not aware of that - could you elaborate?

In this video, Mitch's definition of "State of the art DSP" is: "it can do excess phase correction". EP correction is only possible with linear-phase filters, which means FIR. Linear-phase FIR is the only type of DSP that allows you to adjust amplitude and phase independent of each other. Well strictly speaking that's not true, you could use all-pass filters to adjust phase independent of amplitude which are available in IIR, but it's not the same fine grained control possible with linear-phase. Play around with manual DSP correction a bit and you will see what I mean.

I pestered Mitch via email to enquire about the availability of this unit. He said it's undergoing testing, and it will be ready for the market when all the bugs are ironed out. He wouldn't give me an estimated time line, so here's hoping that he has enough testers and he can fix problems quickly!

 

[welwynnick]

In this video, Mitch's definition of "State of the art DSP" is: "it can do excess phase correction". EP correction is only possible with linear-phase filters, which means FIR. Linear-phase FIR is the only type of DSP that allows you to adjust amplitude and phase independent of each other. Well strictly speaking that's not true, you could use all-pass filters to adjust phase independent of amplitude which are available in IIR, but it's not the same fine grained control possible with linear-phase. Play around with manual DSP correction a bit and you will see what I mean.

Thanks Keith, that's what I was hoping. There are lots of tools that compensate amplitude vs frequency, but only a few that compensate phase vs frequency as well.
That's my particular interest, as it helps to fix loudspeaker problems as well as rooms, especially 3-way speakers that have awful phase response.
There are a few digital active speakers like Neumann KH150 or Genelec 8380 or Buchardt A500 that have effective internal phase correction, and great transient response.
However I'm hoping that off board amplitude AND phase correction using the HLP or similar will give the same benefits with passive speakers as well.
I've been following Mitch Barnett for a while, and a lot what he says seems to revolve around fixing in-room bass problems.
So I was afraid he was prioritising low frequency correction and amplitude correction, over mid-range correction and phase correction (which helps transient response).
To illustrate, here are the phase and step responses of the otherwise wonderful (3 way active) Neumann KH420:

And here are the phase and step responses of the Neumann KH120 II with internal phase correction:

The ingredients for good time domain response seem to be flat amplitude/frequency response, plus flat phase response to within +45deg from 200Hz upwards.
Alternatively the group delay needs to be flat within +0.5ms from 200Hz upwards, which is broadly what Genelec achieve with "Extended Phase Linearity":
I was impressed with what Mitch achieved with Tekton speakers in-room, so I'm hoping to achieve that with an immersive system & passive speakers.

 

[Keith_W]

However I'm hoping that off board amplitude AND phase correction using the HLP or similar will give the same benefits with passive speakers as well.

Yeah, bear in mind that that HLP is only going to be as good as the filters you generate for it. So software and some skill is important as well.

The other thing that Mitch told me is that it is going to be completely agnostic to filter design software, which means you can use anything you like to make FIR filters. If I were you, I would give LinFIR a test drive (since it is free). Otherwise you could use Audiolense or Acourate. Mitch wrote a book on Acourate, and so did I. The difference is that his is an actual book and mine is more a collection of recipes which does not attempt to educate or guide.

 

[welwynnick]

The difference is that his is an actual book and mine is more a collection of recipes which does not attempt to educate or guide.

Well, I did like these threads, and they both firmly reside in my favourites folder:

A comparison of convolution engines

Introduction Some members have systems where the audio crossover is performed by the PC. These are typically .WAV files that contain all the information required for the crossover to function: high and low pass filters, driver correction, room correction, delays for time alignment, etc. A...

www.audiosciencereview.com

Understanding the state of the DSP market

I thought I would make a public service post about DSP, because I have noticed that many people don't seem to understand it. I hope this post helps you understand what a DSP product offers you, what the advantages and disadvantages are, and ultimately help you choose what you want or need. This...

www.audiosciencereview.com

 

[welwynnick]

And this one of course:

ASR Acourate users

There are a number of threads about Acourate on ASR, but there does not seem to be an "Acourate user group". There is an actual Acourate User Group, but that place is pretty quiet and full of existing Acourate users. I thought I would create a thread so that we can discuss and share what we are...

www.audiosciencereview.com

 

[EJ3]

With the looks, it clearly looks aimed at the professional market. That's unfortunate IMO to only focus on that market. Sure, DIY people who generally don't care about aesthetics will also buy it. But for the general audio home market, the looks of the unit is terrible.

I think that it looks great. And would fit in just fine with my gear (none of which is "Pro" gear).

 

[dziemian]

Great idea. Separate box with uploaded filters without restrictions.

 

[dziemian]

I used Deqx PDC-2.6P many years ago as a preamp and always thoght it would be a great device if they let other filters be uploaded as well. Prioprietary software was the biggest limitation and still is.

 

[Kal Rubinson]

I used Deqx PDC-2.6P many years ago as a preamp and always thoght it would be a great device if they let other filters be uploaded as well. Prioprietary software was the biggest limitation and still is.

As well as the lack of support for multichannel.

 

[dziemian]

I was using it for stereo plus two subs so had no problem with multichannel. Then I compared the sound with cheap Echo Audiofire 12 channel interface and htpc and there was no way back. In the meantime I had also tried Minidsp NanoAVR HDA. I liked it but there were too many problems with hdmi input. So I am looking forward to Mitchco's processor and its price.

 

[pablitho]

So the HLC device will be linkable to an HTPC ?
The HTPC will correct video through MADvr then you'll have audio correction through HLC...If it will be DANTE capable everything could be done in the digital region, so just one DA conversion , best of worlds!!!
Hope the wait will finish soon....

 

[Naturlyd]

A standalone convolver? Take my money. Pretty please (*).

Got the impression that the @mitchco operation is a one man band so kudos to the ballsy aspirations. Just wow!

If there ever was a need for a Kickstarter, this is it. Please consider.

(*) Goals for 2026 is/was learning how to master setting up a headless Win pc as a convolution engine. With remote filter change.