Changed rooms, now sounds dire. Suggestions pls...

Room correction with a DSpeaker antimode2 or a miniDSP unit is a good option here if you prefer to avoid bulky and expensive bass traps.

The DSpeaker nicely corrects my 50hz room mode of 15db and a smaller one around 75-80hz and makes a surprisingly good source paired with a decent budget streamer and used as a DAC (I feed it digital from a Bluesound Node2 and the combo sounds more live, dynamic and natural than a thousand pound source has any right to).

The advantage of DSP room correction is that it fixes the mode without swallowing up other unaffected bass frequencies, which can be an issue with bass traps. 

One disadvantage with the DSpeaker for your situation is that it only has optical digital input which would mean either changing your ND5XS or feeding analogue to the dsp, although there are quite a few ways to run it depending on the rest of the front end.

I don't think you quite understand how bass traps actually behave in a room.

The term Bass Trap is something of a misnomer - they don't actually "swallow up" the bass, they stop it being reinforced by excessive resonance.

On the other hand, the problem with using a DSP based solution with full rage speakers is that the DAC and analogue circuitry in the DSP isn't anywhere near the quality of the DAC and analogue circuitry of the NDX, so although it doesn't apply digital filters to the midrange, it's DAC simply doesn't do as good a job with the mid frequency sound, hence there's an overall loss of quality by processing through an inferior DAC.  Even if you use the DSP in the digital domain only, there's still time smearing and other effects extending into the mid frequencies, that still to some degree degrades the signal quality when compared to bit-perfect reproduction.

The answer to this is to have a sat-sub system, using main speakers where the bass extension is sufficiently truncated so as to not excite the fundamental room resonances, and then only use the DSP to process the signal going to the sub, leaving the main speakers unaffected.

I understand your point Huge, but there are options here and each solution involves compromises but should be on the table. Most people are used to *some* in-room bass reinforcement, so sound can then require some acclimatisation if suppressed by bass trapping. 

NDX ultimately may be better streamer/DAC than the Node2/antimode2 combo, but the OP has a ND5XS. In a room with significant problematic bass modes I would bet on the DSP combo with auto-correction to give better sound every time than a higher end source with no correction or trapping applied.

Bitperfect and hi-res are pretty much useless if the sound is being messed up by strong bass modes. I agree bass traps may be preferable but judiciously applied DSP can work really well without cluttering up the room. The Antimode2 only corrects the bass frequencies, above 200hz is left untouched. It can be used for 2ch or as crossover control for a sub-sat system, with fully automatic setup using its provided mic.

Another advantage for me here compared to changing speakers in order not to excite a resonance is that I got to keep my full range speakers with good bass down to 38hz, rather than changing to limited-bass speakers and losing the entire bottom octave just to correct a specific 50hz mode.

NB: I just sold a very highly rated Schiit GungnirMB DAC because the bass timing sounded off/slow compared to the Antimode2 internal DAC. Since making this change I have been able to stop thinking about gear or analytic listening, as my system is just giving me wonderfully addictive music. 

I placed my speakers on Isoacoustics Gaia's (there are many other products from Townshend, Netpoint etc.). With the speakers in the same position it considerably tightened the bass. This is in a room with hard wooden floors. Perhaps your friendly dealer might lend you some acoustic isolation products to try?

I just added some GAIA 111s on the weekend to my Dynaudio XD 600s remarkable product,that definitely tightened up th bass in my room.

DC71 posted:

I understand your point Huge, but there are options here and each solution involves compromises but should be on the table. Most people are used to *some* in-room bass reinforcement, so sound can then require some acclimatisation if suppressed by bass trapping. 

NDX ultimately may be better streamer/DAC than the Node2/antimode2 combo, but the OP has a ND5XS. In a room with significant problematic bass modes I would bet on the DSP combo with auto-correction to give better sound every time than a higher end source with no correction or trapping applied.

Bitperfect and hi-res are pretty much useless if the sound is being messed up by strong bass modes. I agree bass traps may be preferable but judiciously applied DSP can work really well without cluttering up the room. The Antimode2 only corrects the bass frequencies, above 200hz is left untouched. It can be used for 2ch or as crossover control for a sub-sat system, with fully automatic setup using its provided mic.

Another advantage for me here compared to changing speakers in order not to excite a resonance is that I got to keep my full range speakers with good bass down to 38hz, rather than changing to limited-bass speakers and losing the entire bottom octave just to correct a specific 50hz mode.

NB: I just sold a very highly rated Schiit GungnirMB DAC because the bass timing sounded off/slow compared to the Antimode2 internal DAC. Since making this change I have been able to stop thinking about gear or analytic listening, as my system is just giving me wonderfully addictive music. 

There are a couple of points here

You are obviously sensitive to the amplitude of the bass frequency mode of the resonant peak but not sensitive to the reverberation time (the Antimode device only affects the amplitude of the resonant peaks making them less noticeable, it doesn't reduce the reverberation time).

You say that "The Antimode2 only corrects the bass frequencies, above 200hz is left untouched", however unless you are using it with a sub (and only with the sub!), it's acting as the DAC for the WHOLE audio range not just below 200Hz so although the DSP filters may be set below 200Hz, the device is still affecting the signal above 200Hz.  Furthermore there is an inherent loss of quality in the whole of the audio range as the digital signal itself had been numerically processed and is no longer 'bit-perfect', hence it needs another layer of dither to be applied.

The DSpesaker connection examples document only illustrates the use of the Antimode for use with a sub - it isn't even intended for full range operation in a high quality set-up!

In no way will I believe that the (£300) Antimode DAC and analogue circuitry is anywhere near as good as the DAC and analogue circuitry of the  (£2000) ND5 XS! or even the analogue circuitry of the Nait 5i.

Using an Antimode will reduce the amplitude of the bass peaks for the streamer, but will have no effect on playback of CDs.

Finally, using a combination of bass traps to reduce the reverberation and a DSP controlled sub to provide a room tailored bass response (down to <28Hz) will produce a much better result than the limited effect of a DSP on it's own.  I know this both from theory and also from practice as I've tried all the variations to quell the fundamental resonances in my room.

Well it seem that a free solution to that bass problem is too simplistic and therefore have to be complicated and expensive... 

cat345 posted:

Well it seem that a free solution to that bass problem is too simplistic and therefore have to be complicated and expensive... 

The only free solution is move back to the other room!

Huge posted:

cat345 posted:

Well it seem that a free solution to that bass problem is too simplistic and therefore have to be complicated and expensive... 

The only free solution is move back to the other room!

Not if that get you into divorce 

Huge, mostly good points, except that I'm talking about Antimode2. You are right the original Antimode is for sub correction only. V2 is usable as a DAC/DSP for a 2ch full range or sub and sat combo, covering bass correction and also crossover duties for the sub-sat combo (by way of dual analogue outputs). And like I said, in a problematic room with strong bass modes the budget streamer plus DSpeaker unit will easily give better sound than an ND5XS on any material which excites the mode.

Fully agree with your last paragraph though, a combination of correction and room treatment would give the best solution in terms of sound quality.

Don't dismiss the antimode2 because it is 'just' DSP. It is purpose designed to reduce/fix the effects of bass modes and it does this very simply and well IME. In my system it also beat out a DAC which many people rate higher than ND5XS, DACv1 etc. (Gumby)

Thought an update might be in order.

Moving the PMCs away from the wall helped a lot as did putting in a bit of soft furnishing, so most of that boominess is gone. Our life patterns have changed though and I no longer get a couple of nights per week to enjoy the music in an empty house, so it sounds better but the opportunity to use it properly doesn't arise that often.

Reality is I really don't mind. I had a spare tuner and really missed not having decent radio in the living room so a trip to Richer Sounds over the w/e relieved me of £100 for a v basic ex-demo Cambridge amp and a pair of diddy open box bookshelf speakers that fit nicely without dominating, and it sounds surprisingly good. Better still I can just enjoy it for what is, a v clean R4 & R3 + occasional R2, without feeling the need to wonder how much better it could be. I know the answer to that, it's in the other room.

You have done the right thing ..... move the speakers out into room as much as you can ..... then if you move your listening chair around the room you will get hot spots of bass ....... try and locate your desk chair away from a hot spot. I have a small room .... and use 20.21 pmcs  ........ on a 500 system ... they are very demanding little speakers ..... I would imagine the 23's would be worse. So when you can a better amp would make a huge difference and tighten bass........at the moment the 5i will not be controlling low frequencies...... you really need something like a supernait or nap250 on the end of those.