Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems Sub vs better DSPs for 2Ch?

But will it work? See my post above about apodising/MHR? Also, it would really be for full range speakers, as the concensus on this thread seems to be subs aren't necessarily a good idea for stereo setups, in which case I'm not sure how you'd correct only the bass.

The suggestion for 2-Ch room correction is really beyond this thread, but just surfaced as a result. It's not something I'm desperate for, the 818 sounds amazing as-is, and I'm investing in room treatments at the moment, but it might have merit, and be a way of marketing/selling their existing 2-Ch customers an add on, or attracting new (non-multichannel) customers to the high price point of the 818, as the favourable response here might initially indicate? I'd certainly invest in it, at the right kind of price and it sounds like others would too.

It's just a lot of people are into RC for 2-ch these days and a solution which is fully integrated and which Meridian make money out of might be cool.

The notion that subs are not needed for Meridian full range speakers should be dispelled I have the 6000's and have a set of SERIOUS subs that cost more than I paid for the 6000's.


The effect of a sub and better still multiple subs is to smooth the room response, resulting in better bass response at listening position and, if you are into HT, at many other positions in the room.

Subs will actually work even better in small rooms than large ones as small rooms have far more bass problems with standing waves than large ones, the sub can help smooth these.

Obviously being able to cross over the main speakers so that you relieve their bass units of extreme LF duty has merit too, add in the fact that a sub will fill in the bottom octave.

You don't have to play Dubstep at ear splitting levels or organ music to hear what a sub does to the overall sound.

When setting up a sub, many fall prey to the notion that if they have paid a lot for the sub, they should hear the big bass when playing anything; this is a recipe for disaster in most cases.
You should not "hear" the subs kick in when switching between sub and no sub in respect of a lot more bass (unless of course you have speakers severely lacking in bass) less is more...

It is very easy to compare with and without subs in my system by either scrolling between Stereo and Direct or setting up 2 inputs on my 568, one Direct and one Stereo.

Listening to just about anything with the subs on, the initial impression is of a LOT more spatial detail, the imaging becomes more precise and the soundstage or venue ambiance expands.

Where there is extreme or a lot of deep LF content, you hear it and it sounds a lot more effortless. Double basses etc. sound a little fuller and more natural, orchestral stuff just soars...

Going back to a no sub scenario (Direct) , it all collapses a bit.

Whether you want to spend money on a quality sub/s for all this is up to you - a cheap underpowered sub with a compromised driver, will make things worse; so trying to get the good stuff using one will underwhelm you, leading to a "all subs are rubbish and slow and hard to integrate" state of mind.

Conversely, spending big money on quality subs and just plonking them down in the room will also "waste" your investment , it takes a while and lot of placement and x/over and level adjustment to get it right, bank on a few weeks.


As I stated in the thread where I referenced miniDSP - you CAN correct the sub only channel in the digital domain, regardless of whether you have analog or DSP subs without messing with the main speakers signal.
Even if you wanted to correct the low bass of a boomy pair of main speakers that has all the apodizing / bells and whistles and upsampling etc. - the effect you get by reducing the boom is an order of magnitude above any other "improvement".

There is also a cheaper way to optimise any Meridian speaker.
That is to start by treating the rooms first reflection points in respect of HF/mid reflections, add some bass trapping in the corners if you can. However, a lot of folk CANT do this, so the SINGLE most effective free bass tuning thing is to mess with the listening chair position and *then* the speaker positioning.

The listening chair can either be in a node or an antinode (and all rooms have nodes or anti nodes) and by moving the chair you can get in and out of them depending on your taste and bass problems, merely moving 30cm back or forward can do this - just try it by leaning forward when listening and hear how the bass changes.

Nice post Rodney.

Hi 3dit0r,

I have a room thats 24x18x9 ft. I have the old DSP5000s and one of the best bang for buck improvements I have made to my setup was to add a sub.

The sub I added was an M&K850 I think which has a 12" driver and a 125W amp in a closed box. It cost me �400. The amp is not that powerful as subs go, but it is a reasonable quality sub and goes down to 20Hz.

This sub's recommended placement according to M&K is in a corner and it works fine like that. If you place it in the middle of the room, it struggles a bit. Apparantly, each reflecting surface add x dBs, so I've read somewhere...

I have done a direct comparison with a friends BK Monolith which had a 300W amp and also has a 12" driver, which was a ported type box was twice the size and weight of my M&K. It can go to 17Hz I believe.

The Monolith was better all round and was much more flexible in its placement. It could be placed anywhere in the room as it had a bigger amp and could cope far better with the node/antinode/room response effects talked about elsewhere.

The Monolith sells today new for �450 - �650 depending on amp size and finish. They now produce a 300W and a 500W amp version. It has had really good feedback from many and for that amount of dosh, you can't go wrong.

If you found after trying it, it wasn't for you, or you wanted to upgrade to a higher quality, it would be easy to sell without too much loss.

If you integrate it well in your system (which I haven't found difficult), you will be amazed at the difference and Dubstep/organ is just plain awesome... at any level!

eBay - BK Monolith-DF Subwoofer will give you some idea. You don't have to buy through eBay... you can go to the company direct through their own website.

Regards

Thanks Rodney, that was a really informative post! I totally understand what you mean about using subs to smooth out room response - is it basically that you place subs where there are nulls, etc.? I have always played extensively with listening, and speaker position to get the best balance out of a system in a particular room, so with you on that too.

With you on room treatment is being added a little at a time, to first reflection points first. I'm using GIK acoustics stuff, which seems to be good!

I haven't got time today to read through the miniDSP site you sent, but I will later on tonight when I can absorb it. At first glance, I do wonder if it's a little technical for me in terms of hardware mods, etc. - you seem to be quite able to be hands-on with raw tech a little more than I!

Thanks Tim, it does seem there is some love for subs too then, good to know. The consensus does seem to be they work well if you can integrate them into the system well.

Had a very brief phone conversation with Meridian support (very pleasant people!) during my lunch break, and suggested the idea of a 2-ch MRC card for 818/808. The guy didn't seem surprised at all, apparently it's not the first time stereo MRC has been suggested, or discussed in-house (although perhaps not specifically for 818/808). Apparently M are fully aware they have a large 2-ch customer base who are unlikely to ever buy something like an 861, when they're not interested in multichannel.

Apparently back in the day, they debated whether to make MRC an optional card in the 861, so not an integral part - basically, the idea was that in some rooms it would only be doing a very minimal amount of correction, so only customers who really needed it would have had to buy it. Interesting! (Also, Ian, apparently it's been discussed in the past including MRC into DSP speakers, so you weren't far off on that one either!).

In any case, it was only a brief conversation, and nothing may well ever come of it, of course, it'll just be passed on to the design team to see if they think it's worth pursuing or not - they know their products, market, and customer base far better than us so I'm sure their decision will reflect that. I'm just working on the old adage 'you don't ask, you don't get'.

ANY system will require measurement first if you want to tune it or the room or integrate a sub.

Whether you have Meridian or not, a few quid spent on a calibrated measuring mic and a free download of REW (from home theatre shack) is money VERY well spent. You can then see where to concentrate your efforts.

MRC is 10+ years old, things have moved on since then and far more powerful and much cheaper and more effective systems and methods have evolved. Reading the "gentle art of room correction" I can see it's now "outdated" in some technical aspects (but not in intent).

Yes, the miniDSP site can be confusing, but just look at any of their products "in a box" , don't look at anything else. The in a box stuff is "simple".

There are no hardware mods to do - you connect the unit into your system and then use a laptop to program it - the programs are really easy to use and you can hear what you are doing on the fly as you are adjusting. You need not have a computer attached once you happy.

Thanks Rodney, I'll definitely check that out later

Rodney, I've been very bad and taken a longer afternoon 'tea' break than planned to look at the miniDSP (my screenplay hates you

Yeah, it's interesting! I can only see how you'd integrate 3rd party subs in an 818/DSP speaker setting, without losing apodising, MHR, etc on the main stereo pair? I'm guessing to do this, you'd feed the main DSPs direct, and use one of their 'sub' settings to roll off below a certain frequency, then run whichever sub you settled on from the analogue outs of the 818, and let the miniDSP box integrate the sub and perform DRC only on the sub itself for bass?

I did try RC once, using a TACT DRC when I had the 5200s and had bass issues, but it corrected the whole frequency band, not just the bass - I didn't get on with it. Based on that experience I tend to agree with Meridian that it's best to only try and deal with big bass modes with DRC and leave the 'sensitive' midband and treble alone (best dealt with using room treatments?).

Does that sound reasonable, or am I missing things, I've only had a brief look?

Cheers.

If you were using a single analog sub or 2 (L sub/R sub) in a Meridian system, the easiest way to start is to use the MinDSP 2x4 - $105.

You would use the 2 way Xover advanced plugin (you just wont use the Xover bit) $10.
Get a Umik1 mic while you about it - total $185.

The 2x4 has 2 analog inputs (L&R for stereo), 4 analog outputs (2 x L&R). You would just use only 2 analog outputs not 4.

Analog out from the 568.2 or whatever is driving the analog sub into the 2x4.
Then do the DSP (6 bands of parametric on each chan input and 6 on each chan output = 12 bands per channel and a whole lot more) and then feed the result to the sub.

In fact with that unit, you can actually tune/integrate/correct 4 subs.

It sounds more complicated than it is

OK, cool. It would be the 818 driving it as the 568 will be going, so I'd do the above steps but set the main speakers to 'sub' settings to roll off, is that right?

Completely agree with Rodney on value of sub(s) and miniDSP.

FWIW, a BK Monolith will reach 17Hz but at some -dB value. An SVS 20-39PC+ or PB12+ will reach 16Hz at at least 0dB if not +3dB in-room. Even 12Hz is possible again at 0dB not the daft -6dB values quoted by some manufacturers. Depends how deep you want to go.

For those interested, Stereophile in January published a miniDSP review by the esteemed reviewer KalR. That, plus Rodney Gold's several posts have given me more understanding of the potential for low end SQ enhancement. I'm working on room treatment for now but believe even when that's done there will still be more to do.