Room correction - Stereo & Surround

[DigiPete]

PS. Renames from CA Surround sound as discussions went that way ;-)

 

 

Have you ever heard highs in surround?

 

There should be a government health warning label on that experience!

It is indeed intoxicating, but slightly difficult to come by.

 

Buy the "The Nordic Sound" blu-ray from 2L, play it on your normal surround system and get hooked!

 

Best highres surround music sources i know are:

 

www.2L.no

24/96 in 5.1 download

SACD / Blu-ray with PCM

 

www.iTrax.com

24/96 in 5.1 download

 

SACD (hybrid CD + multichannel) available anywhere

 

Blu-ray audio desk's with up to 24/96 in 5.1 download

 

DVD-audio desk's with up to 24/96 in 5.1 download

 

and to some extent:

 

Live consert Blu-ray & DVD's with DTS and sometimes 16/48 in 5.1

 

 

How to play:

 

Desks can be played from your blu-ray / DVD / SACD player straight to amplifier or through external multi-channel (professional) DAC.

 

Rips and downloads typically plays through external (professional) firewire DAC's or digital to digital converters.

 

I use MBP -> firewire -> D to D converter -> AES/EBU (rigid professional S/PDIF) -> active speakers with DSP room correction and DAC.

 

Software players:

 

For typical downloads in FLAC and WAW I use Decibel that is a memory player

http://sbooth.org/Decibel/

 

VLC plays everything else including DTS and Dolby stuff, now that higher resolution stuff can be found.

 

I am not sure if you can play surround files extracted from SACD's without going to professional programs or converting to PCM first.

 

I am on a jurney, challenging but fun.

 

 

Check my tagline and blog and then ask questions in this thread.

 

Please chime in if you are interested or have experiences to share with us.

 

[ccclapp]

Digipete

 

Thanks for the post

 

What "external (professional) firewire DAC's" ? I am considering the Mytek 8x192 for mult-ch audio and to feed my 2.2 setup for digital room correction (DRC). What other DACs do you recommend?

 

How have you implemented DRC? Do your speakers do it? How? I'm reluctant to add hardware after my DAC but haven't settled on an approach yet. Any recommendations?

 

Thanks

 

 

 

[DigiPete]

Digital Room Correction

 

I suppose there are three main implementations:

 

A) Software in the computer

B) Internal/external hardware

C) Speakers or systems with integrated DSP

 

A) Software in the computer

 

PureMusic (MAC) and

J River (PC)

 

are both capable of plying music with room correction through filters.

This is by far the cheapest way to implement DRC.

Have a look at www.computeraudiophile.com/content/Active-room-correction

 

B) Internal/external hardware

 

I looked at quite a few that all seem quite good:

 

Lyngdorf DPA-1

One of the first available consumer products, still sounds fine but has not been updated for al one time. Stereo

www.lyngdorf.com

 

DEXQ HDP-3 preamp processer

More of a multitool, capable of x-over as well but aimed at stereo.

www.deqx.com

 

Spatial Computer - offers to set everything up for you - remote.

It is really a software, but they are very restricted in choice of Digital to Analog Converters.

Check out their DAC choices, great pro gear!

www.spatialcomputer.com

 

 

 

C) Speakers or systems with integrated DSP

 

I prefer systems that are made to work together to provide the optimal experience.

These systems are really rare, probably because many audiophiles think they are so clever that they outsmart the professionals. Few do IMO.

 

Meridian

A consumer product that is as propraritary and well integrated as Apple.

Sounds absolutely great and looks stunning.

www.meridian-audio.com

 

Steinway Lyngdorf

SL offers the most insane natural sounding sound producing system probably in existence. Very expensive. Smallest stereo setup USD 25.000

www.steinwaylyngdorf.com

 

Genelec

My favorite and my choice. Genelec produces reference studio monitors.

The Genelec 8200 series active monitors has the DSP room correction and DAC designed into the speakers. Surround systems start at USD 5000

Industrial design, I love it but WAF may be in the negative.

 

The GLM kit (Genelec Loudspeaker Manager) maps the speaker and room reponse and programs careful correction into the speakers.

Set up the mic in one or more positions, press a button and you are set.

 

All you need is a sound card that produces AES/EBU - the professional equivalent of S/PDIF.

www.genelec.com/products/dsp-products

 

[DigiPete]

I like professional sound gear. It's designed to get the job done.

No chromed trimmings, no hand engraved front plates, nothing wasted to boost your ego.

All the effort and the resources is put into the reproduction of music.

 

My pro preferences may be reflected in the following list, but it is all very cheap gear for the quality.

 

Digital to Analog Converters (external)

 

Lynx Studio Technology 8/FW, PCM, $2595?

Firewire DAC + AES/EBU

www.lynxstudio.com

 

Mytek Digital 8X192 Series AD/DA, PCM + DSD, $3,495?

Firewire or USB DAC + AES/EBU

www.mytekdigital.com

 

Apogee Symphony I/O, PCM, $5685?

Firewire or USB DAC + AES/EBU + options. ?Thunderbolt option pending.

www.apogeedigital.com

 

Weiss Engineering AFI-1, PCM, $2,280 (www.vintageking.com)?

?Firewire to AES/EBU only

www.weiss.ch

 

Audio Cards

 

Lynx Studio Technology

AES16 (PCI) & AES16e (PCIe)?$625, $699?

?Analogue + AES/EBU

www.lynxstudio.com/product_detail.asp?i=16

 

RME Hammerfall DSP AES-32 (PCI) $1000??

Analogue + AES/EBU

www.rme-audio.de/en_products_hdsp_aes32.php?

 

 

[ccclapp]

Thanks very much!

 

I am preferring to head towards "A" as i have amps speakers etc and I prefer selection of my own DAC and am trying not to do another a/d d/a conversion after the DAC. ( I see your setup puts the DAC in the speakers)

 

The problem with "A" is for external (non PC ) sources, which as of now can't play in jriver/ pure music ( HQPlayer also allows for convolution files for DRC), although there is some talk that jriver will implement this...)

 

Do you know if there is hardware that will go in front of an external DAC to receive a digital signal from PC or external sources and perform DRC in digital domaine and output to DAC with no conversion? Alternatively do you know a PC DRC solution that will work on external sources ( fed to it from spdif via a PC sound card ) ie source->spdif->sound card->PC DRC ->external DAC ?

 

Partially answering my own question, I know Squeezebox server can be sut up with a DRC plugin which should do this for mog Spotify etc and a hardware source plugged into it, but haven't tried this yet.

 

In all cases I will need multi-ch DAC to receive crossover feeds from DRC . In my case 2.2 (=4)

 

Sorry, I tnow this is somewhat off track from your primary topic

 

Thanks

 

Ps liked your story/ blog

 

[DigiPete]

Pure Music has the play through feature.

They say it should work for both other software and external sources such as CD's. It also allows you to bi-/tri-amp your speakers should you so desire.

 

Amarra also has play though, not sure about room correction.

 

The better pro sound cards have both digital and analogue inputs and outputs.

The right one can be both be your S/PDIF multiple input and your 4-6-8 channel DAC.

 

Mytek Digital 8X192 Series AD/DA, PCM + DSD

would be a great option for your use.

 

Lynx Studio Technology 8/FW

would also be a great choice, for PCM only.

 

They are both great tools, and should give you plenty of options for future development of your system.

 

In the cheaper easier end you can find dedicated systems such as:

 

KRK Ergo

Build on Lyngdorf Audio's "Room Perfect" 3D room analyses and corrections algorithm.

Includes DAC's and subwoofer management.

This will get you going fast and cheap including one external S/PDIF.

www.krksys.com/krk-ergo.html

 

DSPeaker's Anti-Mode 2.0 Dual Core.

Room correction unit with digital to digital and also build in DAC

www.dspeaker.com

http://verkkokauppa.planeetta.net/epages/Planeetta.sf/en_GB/?ObjectPath=/Shops/vlsi/Categories/DSPeaker/Antimode

 

Anyway, good luck.

 

[ted_b]

as two very reasonable and extremely musical multichannel DACs. For the value side, there is the Steinberg MR816. I've had all three in my home system.

 

I'll be getting a Mytek 8x192 soon, too. MCH DSD and PCM, with software channel trims and delays (so as to go as direct to amps as possible) is my goal.

 

Decibel will play multichannel FLAC and multichannel wav ?

 

Great thread!

 

[ccclapp]

Ted: I have been looking closely at the Mytek 8x192. I have had an email exchange and am scheduled to speak by phone with the Michal, the head of the company to discuss it further in the context of what we are discussing: mult-ch playback and multi-ch for DRC/Crossover purposes. I posted questions about the unit in this context on the main Mytek thread on the lower 1/2 of this page (don't know how to link to a specific post in a thread). There was some reply, but clearly I need to go to the source (Mytek) for full info:

 

http://www.computeraudiophile.com/content/Mytek-Stereo-192?page=3#new

 

DigiPete: Thanks again for all your product links. I've seen some of these, but your targeted referrals save lots of general search time (which I know you put in, as have I).

 

It seems to me that "A" above is still the way to go for me (PC-based DRC -> great multi-ch DAC) I am glad to hear from both of you that more players are doing advanced DRC and some are/will cover external sources.

 

As Ted says, I too want to have as little as possible in the signal path. In concept this could only be PC->DAC->(Amp)Speakers. Further, I prefer the open nature of PC based DRC vs propriety closed hardware solution. The whole concept is enough of an "audiophile bastardization" that I want to be very careful. It is also very much cutting edge for better and worse and I want to be sure I remain nimble to be able to exactly meet my needs based on the ever-changing technology. At the moment, having the flexibility to try/use REW, DRC, Audiolense, Accurate and others to create convolution filters based on their own algorithms, and then to be able to load those into any number of players or hardware units that I find most helpful and least destructive is great (although clearly more work than a packaged system). There is more and more focus on time-domain (reverb/reflection) correction and the balance between that and frequency response correction and getting the two in "maximized" harmony (can't say "perfect").

 

I don't know about the others, but I understand JRiver's latest release has implemented DRC in a very sophisticated way, I believe using 64bit filters (this may not be the accurate/best description).

 

DigiPete: We have taken your thread 50% of track (more talk of DRC, but in the context of multi-ch). If you endorse this, you may consider changing the thread title to reflect this (by adding Room Correction, etc to the name) so others interested in this topic will join. This discussion is fairly progressive on CA.

 

Thanks

 

 

 

 

[DigiPete]

Decibel is simply a gem for playing multichannel FLAC and wav.

 

Drop a iTrex or 2L download directly into Decibel and you are there!

Alternatively convert the Pink Floyd Immersion DSOTM or WYWH and have a go at it.

 

I have not heard:

 

Metric Halo (LIO-8)

Prism Orpheus

 

but I thrust both to deliver great sonics.

 

Apogee Symphony I/O would have been my choice, had I needed more than just AES/EBU output.

 

My Weiss AFI-1 does that with stunning precision.

I think surround really needs the ultimate internal clock/jitter reduction.

Then it can not only live up to, but far exceed soundstage of the usual stereo setups.

 

Newbees that just want to get their feet wet could start with:

 

Steinberg MR816.

Behringer ULTRACURVE PRO DEQ2496

 

While very cheap, they deliver far beyond the price tag.

 

[ccclapp]

...don't forget MiniDSP $125

http://www.minidsp.com/

 

I ordered one yesterday just to do some experimenting. It will be after the DAC and does a/d d/a so its just to mess around. Having said that, I have heard great comments.

 

There is a very good 3rd party tutorial by a DIY speaker designer on HIFI Zine called "SUBWOOFER EQUALIZATION AND INTEGRATION WITH THE MINIDSP 2×4"

 

http://www.hifizine.com/2010/09/subwoofer-equalization-and-integration-with-the-minidsp-2x4/

 

Even for those not intending to use the minidsp, its has lots of great info on DSP for bass and crossover control (meaning DRC)

 

[ted_b]

become good friends with Michal over the past months. Those guys are going a mile a minute, but several have commented that they are hard to track down. If you find you can't get to him for resolution ping me and I'll have a go.

 

I have no problems with DRC, but I think the players need to mature in multichannel first, frankly. We need software players that will allow all mch formats (DSD, PCM for dedicated mch audio; DTS's HDMA and it's lossy cores, Dolby TrueHD and it's lossy cores for mch audio/video or at a minimum ripped audio from BluRay) to "play through"..i.e the players don't necessarily need to do the HD codec but need to handle the playback, the channel trims, the delays (which is a huge trick with DSD but Miska is on his way to solving).

 

[DigiPete]

ted_b "I have no problems with DRC, but I think the players need to mature in multichannel first, frankly."

 

Jup, multi-channel audiophile playing has been greatly ignored.

 

I have to resort to VLC if files are not converted to FLAC or WAW that I can play through Decibel.

 

J River may be the answer to that. I'm however reluctant to downgrade to a PC that has no Thunderbolt for fast external storage. I reserve Firewire for my Wriss sound card.

 

Has anybody tried surround music with DRC through J River 17 yet?

 

 

 

[ccclapp]

On the topic of players:

 

When designing for the goal of PC based DRC to minimize hardware and a/d d/a conversion, I run into limitations of external sources, being streams such as MOG, Spotify, etc and also external hardware, e.g. Tivo, etc, etc.

 

I was posting a link to this thread on @michco's CA blog and reread his excellend DRC writeup here:

 

http://www.computeraudiophile.com/blogs/Hear-music-way-it-was-intended-be-reproduced-conclusion#comment-131200

 

In it, he states the following:

 

"You can also use a standalone Convolver like Savihost: http://www.hermannseib.com/english/savihost.htm This means that it can convolve any music source like Spotify, MOG, Netflix, whatever you are listening to in real time."

 

I dont know about this, but have asked him for clarification. This could solve one of the two limitations. @Digipete states that other players will handle external sources. Getting closer...

 

 

PS: @mitchco's blog referenced above includes a very detailed 3-part write-up on his DRC experience with lots of great info, visuals and user discussion. Its called "Hear music the way it was intended to be reproduced"

 

[bleedink]

That does it!!!! I am making a pilgrimage to Ted's house! You have way too much audio equipment for one man to enjoy! FWIW I am comfortable on the floor of your AV room.

 

[esldude]

Tact is worth looking at for the middle hardware solution. OP looks like he may have decided to do it in software which actually would be my preference or at the speaker end.

 

Haven't used Tact's multi-channel set ups. Their stereo equipment does an amazing job. They have put most of their efforts toward multi-channel. I believe multi-channel or surround can be better than stereo. Tact and Lyngdorf were together at one time btw.

 

My problem is mainly in two areas with surround. I think I do better with two quality channels vs. several mediocre channels. Not saying surround cannot be done with high quality. Only that I cannot afford to do it that way. The second issue is music only or music oriented recordings are not as available as stereo sources. That is improving all the time however.

 

Finally you are on to something good here. Room correction is a huge improvement even for quite good systems. It is where many audiophiles would benefit by far the most to concentrate their efforts. I guess the fact there is not yet one definite best approach to take is what hampers it. Plus there is more of a market in hardware than there is to correct the hardware you already have.

 

[ccclapp]

Ted:

 

No, I forgot you were a Mytek beta tester, how nice! I may hit you up for some questions...One right now would be: you must know this is not the same DAC chip at on the 2x192. Have you heard it / compared it to the 2x192? In our correspondence, Michal describes is as "warmer" in the low/mids. That description doesn't bother me and may be a good think, given the 2x192 is so/too "pure". Given small differences, would you say this is "as good as" the 2x192?

 

I looked closely at the Halo LIO-8. It looks very interesting. Would you clarify a few things for my less experienced brain:

 

--Would you say its SQ is "as good as" mytek, which is to say, exceptional?

 

--Am I correct it has attenuation control for the 8 outs? If so, would this be all that is necessary to amp/speaker and would the attenuates output be up to par vs other solutions?

 

--I've never fully understood pro vs consumer digital signals. Could the DB25 connector receive consumer s/pdif, etc, i.e. Will I be able to connect consumer external sources? If yes, would it decode multi-channel from blueray, tivo, etc, etc, or only stereo? If no, I expect I could routh these through the PC (and get DRC), but its nice to know I done NEED to use PC.

 

--It ts firewire driver lists only Mac. Ditto its related software. Is it PC compatible?

 

--It seems to allow for remote-control operation. Do you know if this includes volume per channel and/or switching? Speaking of which is switching fixed 1:1 or matrix?

 

--Interestingly it supports dsp plugins. You don't suppose it could receive the DRC correction files we make, do you? That would be a pretty extraordinary solution.

 

--Anything else I should have, but didn't ask

 

PS: Ive asked in order of importance, if I tire you out..

 

...yes, but the downside of having so much equipment is you get people sleeping on you floor and pestering you with endless questions ;-)

 

Thanks!!!

 

[ted_b]

but it has great SQ. I have NO idea vs the 8x192 cuz I haven't ehard the 8x192. And yes, as I stated earlier the 8x192 does not use the SABRE chip, so its SQ is going to be different than the stereo192. Michal also told me it is a bit warmer/lusher in the mids. Fine with me, either way.

 

The MH DACs need a MAC to set up, but then can be run without a computer if needed. No, there is no pc console, though.

 

The MH DACs use a Mac console and can be directed via the MAc to do channel trims and delays (the extent of which depends on whether you opt for the standard DSP or optional add-on). I tried the LIO-8 in direct-to-amp mode, but liked a preamp inbetween much better. YMMV.

 

I never tried the LIO-8 in multichannel mode (had no software player to use at the time). But it's XLR and DB-25 inputs and outputs can accept coax SPDIF via simple BNC to AES impedance transformers (inline adapters) like the Canare BCJ-XP-TRB.

 

[ccclapp]

Thanks Ted!!!

Oh, yes, it was you who first told me about the 8x192 vs 2x192 chip difference. Sorry.

 

[mitchco]

Hey ccclapp

 

Here are a few links that may be of interest as JRiver now supports a native convolution engine and does not require the convolverVST plugin. Also, JRiver has an experimental loopback feature so you can watch Netflix, listen to MOG, etc., through JRiver’s native convolution engine. That way you don’t have to use Savihost to host the convolverVST plugin in standalone mode.

 

Lots of good info here:

 

WASAPI Loopback (experimental feature) : http://yabb.jriver.com/interact/index.php?topic=70242.0

 

Native JRiver 64bit fp convolution engine for Room Correction (FIR filters)? http://yabb.jriver.com/interact/index.php?topic=68828.0

 

Microphone measurements and convolution setup: http://yabb.jriver.com/interact/index.php?topic=69312.0

 

Also lots of good stuff on the REW forum: http://www.hometheatershack.com/forums/rew-forum/

 

Audiolense User Forum: http://groups.google.com/group/audiolense

 

I also know that a few other members of CA are using DRC in a 5.1 setup with JRiver. Hopefully they will join the discussion.

 

Cheers!

 

 

[audiozorro]

You can take my word on it. Anyone with a mid-fi home theater system knows that. But if you doubt me, try this experiment:

 

1. Buy an excellent and affordable multi-channel player. I recommend the Oppo BDP-95.

 

2. Buy inexpensive but musical speakers. I recommend three pairs of the Audioengine 4 or 5 speakers and one Audioengine S8 sub. You will need speaker stands, such as the low cost Pangea stands so that the speakers are at ear level and located appropriately for stereo or surround sound. The Audioengine 5 speakers are powered but for the Audioengine 4 speakers you will need a multi-channel amp or receiver.

 

3. Play the best multi-channel and stereo music that you can find, preferable the same albums with both multi-channel and stereo formats for direct comparisons.

 

4. Sit back and enjoy. It is no fair contest. Multi-channel will be the hands down winner.

 

 

[bleedink]

The main reason I prefer multichannel audio is it forces me to sit in one spot and actively listen to the music. I find stereo a bit too forgiving for running here and there, multitasking and not taking time to feel the music. Since discovering it I now listen to albums much like I did when I was a teenager. Just close my eyes and enjoy. That to me is the main advantage of MC. Not that a well recorded stereo recording can't contain those same elements but MC cements those effects in the right places. I am not certain whether it is the added distraction of the extra speakers or what have you, but I almost invariably prefer the instruments to be spread out over several speakers. I don't get that closed in feeling I get with some stereo recordings where there are too many instruments competing for the limited bandwidth. The music feels a bit more natural when the instruments are spread out. Personal opinion of course.

 

[ccclapp]

Mitchco

 

Thanks for the links...VERY interesting.

 

Am I over simplifying to say: We now have fully PC-based multi-channel playback, including full-scope m-ch room correction (down to the level of each speaker driver) for all sources generated by a computer (which includes: ripped files, subscription services e.g. mog, netflix, DVD/CD in internal player, and possibly more). The only thing not currently covered are external hardware sources, e.g. phono, tivo (Sorry to put those next to each other).

 

That being the case, doesn't it all come down to picking the best multi-ch DAC?

 

NOTE: IS THIS NOT EQUALLY RELEVANT FOR 2-CH, IF DRC IS DESIRED? FOR ANYONE WANTING SEPARATE CROSSOVER CONTROL AND/OR SUB INTEGRATION, YOU'RE NOW MULTI-CH.

 

 

An I missing something, or are we 99% there upon choosing a DAC?

 

[ccclapp]

Ted

 

I've examined the the Orpheus FireWire info and it looks like another top contender (and user friendly for PC/MAC).

 

Features aside, how would you rank SQ from the three: Mytek, Orpheus FireWire, Halo LIO-8?

 

Given features, how would you rank them?

 

[ted_b]

I haven't heard. The MH and Orpheus DACs are very similar soundwise, and the Orpheus (I beleive) may be more pc-friendly. You gotta hear them yourself.

 

[DigiPete]

Hardware - Hell yes.

 

I still miss the multi channel equivalent of J River on the MAC.

 

Any ideas?