Room correction on Nac 272?

I wonder if it’s possible to use a minidsp nanoDIGI dsp box together with my Nac 272?

The nanodigi doesn’t have a dac - the plan is to route the digital signal from the 272 digital output into the nanodigi, apply some room eq, and the route the signal back into a digital input of the Nac 272 before the d/a conversion.

Would appreciate if anyone have information on the possibility to do what I wish to do on the Nac 272.

You can’t take a digital out from a 272 into another DAC and then back into the same 272 again.

Ah ok, thanks for input! but in this case it would be digital out into a dsp box, and then send the processed digital signal back into digital in on the Nac 272. But I assume that would not work either?

No that wouldn’t work, because you’d just have digital loop.

This is a popular question — a “loop” in itself!

You are in good company, and very welcome.

Nick

Ok, ah I wish I had asked about this before purchasing the minidsp box. : )

But thanks for input, much appreciated!

So having a Nac 272 and wanting to keep it for its streaming and pre qualities, because its such a great sounding device, but still be able to have some sort of eq or room correction - is there a work around? Or would I need to apply the eq on the software side rather, before even reaching the 272? It is possible to do in Roon for instance.

Yes, if you wish to use DSP then best done before reaching the 272.

:+1:

From my experience, there is a better solution than that (albeit an incomplete one).

The biggest benefits of room correction are, for most rooms, achieved at the LF end. The benefits within the midrange (such as correction for reflection and multipath timing issues) are much better handled by simple room treatment. With full range DSP systems (affecting the whole frequency range), in my experience, there is always some loss of quality in the midrange, where our ear/brain combination is particularly sensitive to detecting small ‘unnatural’ changes. Even from theory it is inevitable with ‘full range’ room correction systems that there will be some degradation of the midrange signal, but the degree of this could be quite small; in my experience it is easily noticeable.

So, the better solution:
Instead of using speakers that excite all the primary acoustic resonances of a room, use main speakers with a limited LF extension, then use a sub to give the required bottom end. The analogue feed to the sub can be passed through a DSP unit without causing the degradation of signal quality in the midrange.

With this approach, the signal for the (more critical) upper bass, midrange and HF goes straight to the main speakers, unmolested, without any change; the signal to the sub (to which our ears are much less sensitive) is corrected to reduce the over-excitation of the room resonances. The crossover to the sub can also be accurately controlled to ensure good integration of frequency response AND timing, and the delay through the DSP an be finely adjusted to allow different positions for the sub while making allowance for its group delay.

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Thanks for the tip Xanthe!

I have thought about adding an active sub, but I am not sure how to do it with my current setup.

I have a Nac 272 - Nap 250dr - PMC twenty5.23 setup.

Is there a good way to add an active sub in that setup, and if so could I use a dsp for the sub only?

The Tewnty5.23 have considerable bass extension (28Hz claimed), so unless you have a very large room, the main speakers are going to excite the bass resonances anyway (i.e. unless your room is more than 7m in length AND width this approach may not work).

What problem are you thinking you would be able to solve using digital room correction?

Yes, the speakers have considerable bass extension and that is exactly what I would like to reduce/control with an eq. At least try it out. But I will do a measurement to get a more detailed view on what’s going on.

I’m using the Active Tuning Module from Nubert, just to control the low end. Works fine for me. I use the tape monitor on my 202, not sure the 272 has that. It can also be connected between the source and preamp.

Naim did mention that they investigated built in DSP during the development of the 272, but decided against it because they felt that the negative effects on sound quality were too great.

If you really want to try it I would consider one of two possible routes:
If you are mainly looking for low frequency corrections consider DSP on the signal fed to an active sub as Xanthe explains.
If you want DSP across the frequency range, add Roon and use that to control the DSP. This is highly configurable, different profiles can be saved, and they can be turned on or off as required, perhaps to suit different genres of music.
Either way you will want to measure your room, and maybe consider having these measurements professionally used to create filters for you, such as by HAF.

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Thanks guys. If I would go the hardware route and get an active subwoofer, lets say a PMC Sub1 or any other one - does anyone know how to integrate/setup that with the Nac 272, Nap 250dr and PMC twenty5.23?

And, would it then be possible to use the digital in/out (if the sub has that) to connect and utilize the minidsp nanoDIGI box I have to to do room correction only on the subwoofer?

First, and importantly, get an instrumentation mike such as a miniDSP UMIK-? (1 or 2) and a copy of REW.
Then check to see if the excitation of the room resonances from the Twenty5.23s is too large (i.e.the bass peaks quite sharply defined and are already too large); if so, the sub only room correction method won’t work for you with those speakers in that room.

If you choose to proceed:
You need a minDSP 2x4.
Connect the inputs to the RCA outputs of the 272 connect one output cable to the low level input of the sub.
Use REW to setup the mimiDSP to do the crossover to the sub:

  1. Sub level setting: you’re looking for a reasonably even frequency response through the crossover region with possibly a small rise into the deep bass.
  2. Sub positioning phasing and & delay: do not invert the phase, move the position of the sub closer to the listener until the minimum phase plot shows a smooth transition through the crossover region.
  3. Set the miniDSP to combine both input channels into the output channel (i.e. mono out operation).
  4. Room correction: apply parametric cut filters to reduce the sub’s output in places where it is excessively enhanced by the room resonances.

However, I suspect you’ll fall at the first hurdle and that the Twenty5.23s may simply be putting out too much bass for the room.

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I had similar issues with bass response in my room. I used DSP for a while via Roon and filters created by HAF. They worked brilliantly, but this was only of use in the digital domain so my analogue tt was left out and still suffered. In the end as room mods are just out of the question I decided to go for smaller speakers that put less bass out. Made a huge difference and helped make it sound better overall and much better for analogue side now. I recently returned to new filters from HAF as the Room still has some issues that just changing speakers won’t fix and for me its now perfect. I don’t hear any issues at all with this method.

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Picking this up late in the thread, all I would add is that it is better to optimise speaker and listening position first, then room treatment as far as possible/acceptable, and only then look at electronic correction. And never try to overcome a deep dip by boosting a signal, as that can rapidly lead to speaker destruction! Bear in mind that every 3dB boost doubles the amp power, so it doesn’t take much to drive the amp into clipping - and that if a dip is caused by cancellation no amount of boost will fix it.

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Best way is to get a speaker that goes tight up to the wall to handle the reflections as all speakers goes omnidirectional in the bass, has good damping of the bass (a sealed box) in a box that radiates as little as possible.

Unfortunately Naim stopped making the SBL 20 years ago. One of the most clever designs ever made for playing music in your home.

Alternatives are the ProAc Tabs and the strangely named and mysterious Klangedang T1.

I did meaurement in REW and managed to import a correction file into the minidsp nanoDIGI. I put it between my macbook pro an Nac 272, connecting it to a digital input.

Then I played music in Spotify switching between the Macbook pro vs Nac 272 streamer. The first using eq correction, the other only using Naim all the way.

My conclusion is that I prefer the Naim only. Allthough the sub bass is peraps a little bit to much sometimes, I just love the sound and the energy.

When applying the minidsp it just did not sound as good, but still good for sure. I just think that that its not worth it to run everything through that dsp for such small adjustements. This is in my living room.

My studioroom with some genelecs is a dirrefent thing. The room acoustic is much worse in there and the minidsp will probably be very useful in that setup. I did measurement and built an eq curve manually yesterday and I am chocked how big difference there is, in a good way.