Final piece of the puzzle: digital correction in a suboptimal room

Hey guys!

I’m in the process of upgrading/tweaking my system and there’s one "final" piece of the puzzle I need to find.

Current setup:

  • Speakers: Klipsch Forte III
  • Subwoofer: Klipsch R-115SW
  • Amplifier: Hegel H190
  • DAC: Chord Hugo 2
  • Room size: 4*5 meters (roughly 13*16 ft)
  • Four wall-wall corners treated with GIK Tri-Trap Corner Bass Trap
  • Two front wall-wall-ceiling corners treated with GIK Soffit Bass trap
  • Side walls, rear wall and ceiling early reflection points treated with Monster bass traps

Considering the small size of the room and the big size of the speakers, I reached the conclusion that a quite heavy acoustic treatment was needed for both bass and mid high early reflections (as you can see from all the acoustic treatments in my setup). I’m still waiting for the panels to be delivered though (looking forward to!!).

My next move would be that of using digital correction as the final tweak to reach a flatter frequency response curve in my room (or at least in my listening spot). But how?

Few considerations:

1) I’d like to use my Chord Hugo 2 dac somewhere in the chain. I suppose the audio chain will be something like: Macbook --> DSP device --> Hugo 2 DAC --> Amplifier --> Speakers
2) I’d like to have only one digital-analog conversion (carried by Hugo 2)
3) I don’t have a clear budget. I’m willing to spend money if the solution proposed solves my pain in a elegant way. Say 2000 usd max?


  1. What DSP device/software would you suggest me to get?
  2. The Klipsch Forte III frequency response: 38Hz – 20kHz (+/- 3 dB) How should I cross over to the subwoofer? At which frequency? At around 40Hz, 60Hz or 80Hz? And why?
  3. Where should the subwoofer fit in the chain in a way that it gets its input signal converted by Hugo 2?
  4. But then, if I place my subwoofer after the DAC in the audio chain, will the DSP device still be able to control the sub’s input signal separately from the Forte speakers? (so that I’m able to have control on crossover points between speakers and sub)
  5. BONUS: It might be nice to have a system where I'm able to stream wirelessly from iPhone/Macbook (Airplay, Aptx) to the whole chain. Maybe a DSP device with integrated streamer? (furthermore consider that the Hugo 2 is able to do that via bluetooth aptx and the amplifier Hegel H190 is able to receive through Airplay and bluetooth aptx)

Thank you so much guys for your help!!

Hey egoquaero,
Kudos on getting GIK treatment for your room.

I honestly think you have too much speaker here, and are overthinking / over purchasing.

What you are not realizing is how much room gain you are going to get, and how bad the room modes will be. On top of that, with the amount of efficiency (99 dB) you can trade output for bass very easily. This means to me you have tremendous capabilities to produce bass already.

With your choice in mains, get an integrated or pre with built in room correction, and try it without a sub first.

Alternatively, get significantly smaller mains and keep the sub.


Hi erik! Thanks for your suggestion!
However I don’t have intention to change main speakers, amplifier or leave out the subwoofer (bought most of them recently haha :D). I got the Fortes for their impactful management of dynamics and I love it even in my small room. My next upgrade is definitely my house :D
I know that the integration of a subwoofer is always tricky, especially in a small room. However, being a heavy electronic music listener among other genres, I very often incur 20-40Hz frequencies. And I’m willing to sacrifice a bit of imaging, clarity, transparency and so on for those sub frequencies

Hey OP:
Your speakers, tuned properly, could do flat 20-40 Hz in that room.

If you are looking for a dance club experience though, you don't want flat, or extended. You want output!!  That makes more sense. However, room modes will force you to keep the levels low unless dealt with.

Alright, I suggest you forego the outboard DAC, and get a pre with built in DSP. Anthem and Antimode are a couple of brands with very positive reviews which are reasonably priced.

Otherwise, if you must use Chord, and you want to avoid a second A/D / D/A conversion step, your remaining choice is to EQ only the subs.

The issue is, in my mind, those big speakers are already going to be subject to significant room issues, and you need that EQ there.

Now, if you want asbolutely complicated, but you must have your Chord and must have your subs, miniDSP does make digital only EQ's. That is, they are digital in, digital out and will feed your chord.

But I strongly suggest your effort time and money will be best rewarded by using built-in room correction. Tricky does not begin to explain the issues otherwise.

There is another alternative I just thought of, and full disclosure, it's cause I'm selling one!

I have a Parasound P7, highly rated as a 2 and multi-channel pre. I have gone to an integrated, so no longer need separate pre/power amp.

The reason you might like it is that it has built in subwoofer management (but not EQ). 

That is, it has a built in crossover, letting you limit the output to your mains, and sending the rest to your sub, where you can use a very nice miniDSP to control it.

Or you could add three more subs and have much deeper, smoother, and insanely more articulate bass, without the correction. Which will never no matter what you do get you as good as the four subs.

being a heavy electronic music listener among other genres, I very often incur 20-40Hz frequencies. And I’m willing to sacrifice a bit of imaging, clarity, transparency and so on for those sub frequencies

No single sub and no amount of correction will ever get you where you want to be. With four on the other hand it is easy. Also with four the imaging, clarity, transparency and so on is even better. Read some of the Swarm/Distributed Bass Array threads.
Monster traps may be overkill for the side walls.Heavily treating the corners is worth experimenting with.I'm using GIK and four subs to great effect in my smallish room.Two subs wit built in eq  might work very well also.Best of luck as you research your options!
You indicate you're still waiting for the panels to arrive.  Shouldn't you assess the need for room correction AFTER all of your acoustic treatments are in place?
If you have a MacBook try REW, Room Eq Wizard, to have a look at what is going on with your speakers / room... Next, you might try Audirvana to stream from your MacBook to either DAC you are looking at... Audirvana with AudioUnits software plugins will do PEQ etc... REW can generate room correction PEQ filters and Audirvana via an AudioUnits PEQ provide the EQ for your setup... REW and AutioUnits are free and Audirvana is a reasonable price...  And I agree, room acoustic treatment first then additional EQ if needed...  Use REW as your eyes and ears before and after treatment...
Sorry, that should say: REW can generate room correction PEQ filter settings...

Thanks everybody for the help!

@jtcf I’m definitely evaluating the decision of getting more subs. One of the next steps :)

@three_easy_payments: yes, you’re right. I’m just in a hurry to reach audio nirvana for my room :D And I know that the odds of getting perfect acoustics even AFTER the placement of the treatments are against me. So I kind of know that I will end up anyway playing with digital room correction eventually.

Guys, I took a look at Minidsp offerings with Dirac software and I found that the SHD studio might be the missing piece:


As you can see with this structure:

  1. I keep Hugo 2 into the equation
  2. There’s only one digital-analog conversion performed by DACs, since the SHD Studio dsp device is digital in and digital out and it doesn’t mess up with analog signals

New questions:

  1. It seems that I need two DACs? One for the main speakers and the other for the subwoofer?
  2. Is there a way to make the Hugo 2 be the only DAC. So that the Hugo 2 receives two digital signals from the Shd studio and then produces two analog signals. One for the main speakers and one for the sub. This would be ideal, but I doubt it’d be possible.
  3. If point two is not possible, what would be a nice alternative?

I'm realizing now that... I have a spare Chord Mojo! I can use it as the second DAC to give that analog signal needed by the subwoofer.
Does it make sense? The Mojo's got two 3.5mm Headphone Jack outputs.

So basically:
- Chord Hugo 2 giving analog signal to the Hegel H190, which drives the main speakers Forte III
- Chord Mojo giving analog signal to the Klipsch R-115SW active sub
- Both of the DACs receiving equalized digital signal from the SHD Studio

Is there a way to make this happen? Something that connects the Mojo to the subwoofer?
So right now I have rca male-rca male cable for connecting the sub and the amplifier.
I would need a jack 3.5 male-rca male to connect the sub to the Mojo.

Maybe with these?®-pres....ateway&sr=8-10

Not sure about the quality though...
Try and use something like ROON with built-in DSP in the software. The DSP in ROON is not the greatest but it is evolving with every software release.

Also look at the Anthem STR preamp which has a highly rated ARC3 DSP and also sub management.

So there are now 2 choices for DSP in the above 2 recommendations.

You are still going to need a streamer to get the music to the preamp/DAC so look at something from Sonare for high quality at a reasonable price. I use a microRendu and it is on the lower side of the Sonare product spectrum but still rather good. Sonare products are ROON endpoints. You would install ROON server on your MAC and use iPhone, MAC, iPad, Android, etc.. as the client to your audio files and streaming services via ROON.
Well... there's still another conundrum..

What’s the best way to connect the SHD Studio to the Chord Hugo 2?

I know that the SHD Studio’s got 4 digital outputs:

  1. FIRST output: SPDIF on RCA connector / Isolated with digital audio transformer
  2. SECOND output: SPDIF on RCA connector / Isolated with digital audio transformer
  3. THIRD output: AES-EBU on XLR connector
  4. FORTH output: AES-EBU on XLR connector


Chord Hugo 2 digital inputs are:
- Micro USB Input 768kHz (Probably wouldn't work with SHD)
- 3.5mm jack coaxial 768KHz/32-bit capable
- Optical Input 192kHz

  1. Am I able to use both SPDIF output and AES-EBU output to connect to Hugo 2?
  2. Which cable should I use?