[Desertpilot]

If you play digital music files through a DAC, do you use DSP to "fix" room issues and/or speaker calibration?

My situation:
I own a pair of X3s.  I do have some room treatments.  Recently, I installed ROON as my music player which will allow DSP on both PCM and DSD files before sending the file to my DAC.  My X3s are equidistant from the MLP so no timing issues there.  But, I also play multi channel music and want to use my surround speakers which are a different distance from the MLP.  I made this change in ROON DSP to make sure sound arrives from all speakers at the same time.  Pretty simple processing.  But, there is so much more DSP capability.  I may want to add volume leveling.  Or, maybe a crossover to cut deep base tones (i.e., organ music) below 35Hz.  Some folks I chat with said, "No" stay away from DSP or minimize use of it so you don't "alter" the sound.  I know Clayton has already programmed DSP in to the subwoofers.

So how do you feel about using DSP?

Marcus

[abomwell]

I believe DSP is a godsend for bass response under about 300Hz. I've been using it for years with good results. Be careful to use it only to attenuate peaks, not to fill in nulls.

Al

[Don_S]

Yes for removing bass nodes. No for everything else.

[HAL]

Well sent Clayton Shaw a dspMusik 2x8 for use with his X1's as DSP crossovers. 

He seemed very happy with it in his listening with the crossover design I did for him. 

[Desertpilot]

Thanks for the positive responses.  Right now I am only using it for speaker distance.

Marcus

[RonP]

I believe DSP is a godsend for bass response under about 300Hz.

exactly what I've heard as well

[Desertpilot]

I guess my next question is, "How do you implement DSP in your system?"

My digital file is on my NAS.  ROON (and ROON core) is on my PC.  When I ask ROON to play a track, it gets it from the NAS and sends it (via USB) to my DAC.  My DAC converts the digital file to analog and sends it to my amplifier.  The only place I can implement DSP is in ROON.  My PC is pretty robust and can process DSP for ROON.

Is this okay?  Or, is there a better device to hook up in the signal chain?

Marcus

[abomwell]

Both Roon and JRiver have DSP capabilities. Do you have a way of measuring the speakers? One good way is via the OmniMic V2 measurement system:  https://www.daytonaudio.com/product/1052/oomnimic-v2-precision-measurement-system

Another way, which you may already have, is REW. In both systems you would have to enter the currection values manually into Roon or JRiver. I find I can't use Roon and JRiver simultaneously so, if that's the case, you'll need to enter the EQ values into both.

I use a DSPeaker Anti-mode X4 as a preamplifier/processor which
is very flexible and does all kinds of DSP, both automatically and manually. It has 6 presets so I can make adjustments for different recordings or sitting locations. But if I didn't have the X4 I'd use the OmniMic V2 measurement system and manually enter correction values into Roon.

Al

[HAL]

Another option is using MathAudio RoomEQ in JRiver as a VST plug-in for room correction.

It has built in measurement capability with a calibrated mic like Dayton Audio iMM-6 and the online calibration file and others as long as your PC's sound card can run a powered TRRS style mic connection.  Other calibrated mics will need the data file and a mic preamp into the PC sound card. 

I find it very easy to use and sounds very good to me. 

[DannyBadorine]

I love DSP.  It is used in all professional audio applications.  Any concert you go to is using massive amounts of DSP in several different ways to make the system sound better.  My home speaker builds sound better with DSP.  I use mini DSP's for it.  Yes, this usually adds an extra conversion but when used properly it can compensate for room and speaker issues.  Examples: 1) I delayed the tweeter on my MTM living room speakers.  The delay is .31 milliseconds which I'm guessing is about 3-4".  When measuring with an RTA mic on the program Smaart (which is what 99% of live sound engineers use) you can see the phase problems between the tweeter and the mid/bass drivers go away.  They line up perfectly.  With DSP and the bi-amping of these speakers I could try an infinite number of crossover points, frequencies, slopes, etc. and then find which sounds the best.  Then I can use a little bit of EQ to get rid of any problem frequencies caused by the room and my speakers have almost a flat frequency response in the area on my couch where we sit and listen. 
Yes, there are disadvantages.  Danny from GR feels that the miniDSP can "take the life out of the sound" and I understand that DSP is another digital conversation (two actually) and this does change the sound, but if you're already starting with digital from your TV, steamer, computer or bluetooth then I don't think another conversion does anywhere near as much harm as it helps.  But it has to be used correctly.  The room analyzers that do it automatically are basically doing what live sound engineers do.  Our advantage is that we use these things as tools and also use our ears to keep it sounding natural.
One more point, if I may.  I am working on building some speakers with an analog crossover for a fully analog system with record player.  I don't like how my records sound through my DSP.  I agree with Danny from GR that the life is taken out of them.  But that means that I need to measure how much delay the tweeter needs and then do that in the speaker build and get the crossover right.  I could always implement an analog EQ, but EQ is always adding phase shift so you are altering the sound in some way. 
So, I think DSP is better for audio that is already digital.  But when dealing with an analog source, it would make sense to keep it all analog, which means really nicely designed speakers and passive crossovers.

[HAL]

Not all DSP systems sound alike. 

I chose the dspMusik 2x8 as it sounds better than a MiniDSP and an all digital path for digital file or streaming. 

I even do RIAA EQ in the DSP and use the ADC with 40dB of gain with the cartridge for the TT for LP replay. 

[Desertpilot]

Thank you for adding to the conversation.  I plan on running REW soon.  Once I get the measurements, I'll know what direction to take.

Thanks again!
Marcus

[abomwell]

Conventional wisdom says just EQ the bass below around 300Hz. Don't try to fill in the nulls, just lop off the peaks. I'd love to see your measurements!

Al

[Desertpilot]

Conventional wisdom says just EQ the bass below around 300Hz. Don't try to fill in the nulls, just lop off the peaks. I'd love to see your measurements!

Al

I hope to do REW tomorrow and I will certainly post the results here.  I finally found a recent YouTube video that goes through REW step by step (LOL).

Marcus