Upgrade Mordaunt Short Premiere 5.1 speakers to Dali Spektors? Worth it?

NeilF

NeilF

NeilF

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So I have a rather old 5.1 package of Mordaunt Short Premiere speakers, which I upgraded the front pair of:-

And this is all working through my Onkyo TX-NR646 amp and I listen to a mix of music and home theatre etc.


Three considerations:-
  • The current front 902 speakers are quite deep, with one on a shelf, very very close to the rear of the unit. Not ideal (being rear ported)! If I can replace with a less deep speaker, great!
  • I feel the center speaker maybe isn't as good as it could be. It's in a dedicated shelf immediately below the TV, and there's enough room to fit a bigger speaker in there.
  • The woofer feels a tad disconnected, if that's a good term. It doesn't feel tied/combined into audio at times, almost like it's not controlled enough?

So after looking around I'm wonder if a Dali Spektor speaker setup might be the answer?
  • Front: Spektor 1 or if really worth while the 2s - The 2s are 3cm less deep than my existing fronts, so would give an inch more of space on that shelf at the rear. The 1s would give loads more rear space, so would be the more logical choice space wise at least.
  • Rear: Spektor 1 or keep my MS 302?
  • Center: Spektor Vokal (fitting into a dedicated slot under the TV (50cm x 16cm)
  • Sub: C-8 D (down firing) or E-9 F (front firing)

In people's opinion, is that going to give me a good solid noticable improvement in audio quality over my old Mordaunt Short speaker package? Is it going to be £ well spent? ie: My nightmare would be I plug it all in and there's little/no real improvement, as the limitation is the amp, and the Mordaunt Shorts were about the same audio quality etc as any new speakers etc...


There is an alternative of using Q Acoustics 3010i and 3020i? But their sub is definately too big, so I guess I could still use a Dali (or similar) one with it.

Thoughts & advice welcome...
 
lucid said:
What you're describing sounds like the cossover frequency being set too low for the rest of the speakers, and possibly the phase being out of time with the sound in the room. Make sure the crossover control is set to its highest setting, then let the amp's auto calibration do its stuff. Remember too to set all your speakers to Small before doing the mic auto set-up.
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"What you're describing sounds like the crossover frequency being set too low for the rest of the speakers, and possibly the phase being out of time with the sound in the room. Make sure the crossover control is set to its highest setting," - Fascinating. Earlier today I looked at the crossover settings of my amp:-
Front 50hz : The 902s are rate 55hz
Center 100hz : The 304 is rated 100hz
Rears 60hz : The 302s are rated 100hz

I changed them to:-
Front 90hz
Center 100hz
Rears 100hz
And also turned the frequ. for the sub all the way up to max (150hz from probably set to around 120hz).

And I'd have to say immediately music sounded a lot tighter/cleaner. Basically almost exactly as per you comment just now :)
 
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lucid said:
The advice remains the same. Buy a better centre speaker. Buy a better sub. Then work on getting them set up right.
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A sub is a sub, but surely at the moment the "character" of the center MS 304 is very much in keeping with the MS 902 fronts and 302 rears? So changing just the center might undo that benefit?
 
lucid said:
Like I said in your other thread, MS makes more than one centre speaker. For the Avant range, the 304 centre was one choice. The 905c was the other.

Same manufacturer. Same voicing. Same tonal characteristics. Bigger speaker. Better sound.

Simples :D

So no, changing the centre to another one won't undo the benefit of voice matching. Well, not unless you were really stupid and bought a speaker from another manufacture. But that's not what I suggested in the previous thread or in this one, so why would you?
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And as is the way with these things, the 905C is 2-3mm too high to fit into the space I have below my tv in the cabinet. :(
 
lucid said:
That's a bugger. No way to adjust the shelving to fit, I take it?

Well, now you know about MS voicing - which opens up the possibilities of other MS centre speakers past and present - and you're more clued up about blending the sub channel with the centre speaker, and you also know about blocking out the space for the centre speaker to improve the acoustic performance, then you've got enough to go on to play around with the gear you do have to get better performance from the existing centre. Failing that, you can look at well-reviewed alternative MS centres.
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No, can't adjust. It's a dedicated 500x162mm space under TV.

Almost tempting to buy a 905 and see if I can saw off 3mm from it's bottom. But I doubt the wood (mdf) would take it.
 
lucid said:
For example, you could decide to set the 902s at say 70Hz (or 80Hz, which is what THX recommends), then let the AV receiver work out the blend frequency limit for the sub on the front channel bass frequencies that will match.

For the surrounds, rated at 100Hz, you might try 120Hz. Maybe do the same for the centre speaker too.

Setting a slightly higher crossover point takes some of the heavy lifting away from the amp, and that in turn improves the amp's ability to deal with peaks in music and movie sound. Give it a whirl and see what you think.
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Well setting all the speakers to a crossover of 120hz seems the best to my ears music and film wise.

Guess that also makes it simple/consistent for amp too, rather than say having the L&R 902s at 80hz.
 
Well have to say as Lucid suggests moving the cross over up just seems to return a bit of clarity to the speakers, as if not having to worry about those very low frequencies - parsing them off to sub - frees them for a bit more clarity.

Might be me imagining it of course :)
 
Right, some feedback...

I've now got crossover set as:-
Front (902): 80hz - Speaker rated at below 60hz
Center (304): 120 (Amp cannot set to 110) - Speaker rated at 100hz
Rear (302): 120 (Amp cannot set to 110) - Speaker rated at 100hz

That seems to give a nice "connected" sound.


I spent some time clicking the front (902s) between 80hz and 120hz crossover and bunging the rear port with some very tightly rolled up socks. There was a tiny difference, and while with the ports blocked the audio might have sounded a touch "tighter" at times, at others it sounded slight less "bass full", especially for films.

What sold me to do away with the socks in the end was turning the sub off and listening. Without the ports "socked" the 902s definately were a more rounded/full sound. So with so little difference generally, and with the sub off test being in favour of no socks, I settled for a 80hz crossover and put the socks back in my drawer :)

Just a shame the 902s are a touch too big for my shelf, but I can live with that if it means not wasting money on a sideways move.


As regards the center speaker (304) I'm looking for a larger 905i. But as that would be 2-3mm too high for the shelf under the TV, I'd need to cut it down to fit which I'm happy to attempt for a laugh. But this would mean first buying a second hand one, and then doing some "woodwork" on it to crop it down 4-5mm. Could prove a waste of the £70 it would end up costing.

So the risk would be buying a second hand 905 hoping it's still in good audio condition (well over ten years old!). Then risking chopping its case down and hoping that doesn't compromise it.
 
lucid said:
To get a real idea about port bunging, you need to run them bunged but with the amp set to full range. You may have done that, it's not clear from your post, but it's worth mentioning.

The next thing - if you haven't already tried it - is to isolate the speakers from the shelf.

Back when I first started buying Hi-Fi, one of my earliest Hi-Fi memories is a dealer doing this with some speakers when I was buying a turntable. This would be mid-80s. My mate and I sat in his dem room, he tried to explain what the benefits would be. We both thought he was crackers, messing around with little Meccano nuts to make a 3-point support. Nuts would have been the right word, but it worked. Bass tightened up once the speaker was nolonger energising the speaker stand so much. The midrange was a bit better too.

The same principle applies to most things a speaker sits on. Some of that energy gets transferred, and depending on the way it moves then the thing the speakers are sitting on vibrates in sympathy. Since all sound from speakers is the sound of something vibrating (the cones, the cabinets, and what they're sitting on) then the more that energy can be ported away without exciting other items in the room then the tighter the speakers will sound.

If you have some small nuts to use - the metal variety, not the tree fruit ;) - then give it a whirl with those. You could also try small coins. 5p pieces if you can rustle up 6 in your change.
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Well I was trying the speakers at 80hz crossover and 120hz crossover. With and without "socks". Without "socks" at 80hz, the speakers seemed to be the best overall effect. Especially noticable testing with sub turned off.
 
lucid said:
Right, so in all scenarios you're still artificially limiting the.bass output to.the speakers via the amp's speaker set-up menu.

What I've suggested you try is something different to that.

On the amp, you want the speakers set to Large. You want No sub. (Not just switched off... Literally NO subwoofer set up in the system... as if it doesn't exist.) Then you want the.amp on Pure Audio mode so that it's not using any processing. Now try with and without socks.
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Ok will do but There is no speaker size setting on my amp. I assume just set crossover down to 60hz which about the speakers limit.
 
lucid said:
Oh dear God! I've gone to extraordinary length to explain that you want the amp doing no crossover stuff; and your reply "So I set the crossover to 60Hz" Really? [Facepalm moment :rolleyes: ]

Why the hell do I bother? :D :D :D

FFS man, read the bloody manual and set your speakers to FULL BAND.
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...your extraordinary lengths might make sense in your head, but when you talk about setting speaker sizes, which I have no setting for, it's not so clear. [Facepalm moment :rolleyes: ]

I'll do the test as you suggested when I have a min... (ie: Using "Pure" and trying to ensure no crossover etc)
 
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lucid said:
That's why I said read the manual. it's covered in the manual. Take a little time to understand how to operate the gear that your hard earned money paid for. It will pay you back in dividends.
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Yeh, the manual really isn't very clear on "Pure Audio". Clearly the notion behind it is to remove as much processing as possible, so I'll have to have a play. ie: What this means to stereo or 5.1 feeds. I recall it seems to suck the living daylights out of music at least as regards bass, so that does implies stereo in "Pure Audio" literally just feeds to L&R. But a 5.1 source? Surely the sub would still be active, but then crossovers?

I'll have a play...
 
lucid said:
Pure Audio should give you the least amount of audio and video processing that's possible with the particular amp. How that is implemented though varies from manufacturer to manufacturer, and even model to model within certain manufacturer's ranges.

The basic idea is common to all; it's the least amount of processing. For some brands such as Yamaha, in some of their midrange AV-amps and -receivers, it means only the stereo analogue inputs work and the basic DAC for optical and coax work. HDMI inputs get disabled. All surround decoding and processing is switched off. The tone controls are bypassed. The sub out is disabled. The mains front L&R channel speaker connections go to full range. The rest of the speaker outputs (inc sub) go dark. Even the front panel display and HDMI output get switched off. It turns the AV-amp into something as close to a stereo amp with 2ch DAC as it can be. I've used AV-pre-amp processors where Pure means that only analogue inputs work, so you have analogue source selection and volume; that's it.

However your Onkyo does it, for the stuff that it still leaves active, you'll need to change the settings so that the amp isn't interfering with the pure stereo signal going to the front L&R speakers. What you're after is to hear the speakers as if they're connected to a simple stereo Hi-Fi amp. Only then will you be able to really tell what happens between port open and port bunged.

For Speakers: Large/Full Range, see what happens when next you all the way down through the Front L&R crossover settings 120>....100>....80>....60>.... and so on and so on.
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OK... Thanks for the (continued) help... I'll have a play :)
 
OK... A few more observations...

In PURE AUDIO (PA), both in music and film (5.1), blocking the L&R ports (tightly rolled socks) cost bass that otherwise sounded nice. Returning out of PA, and playing around with the front crossover between "full" and upto 120hz (with/without sub), I thought around 80hz gave the best clarity in bass and treble.

The center and rears I flicked between 100hz (their supposed limit) and 120hz, and settled back on 120hz.


One thing I did notice while listening to the opening scene of Blade Runner 2049 in PA, while a bit of the bass seemed to be reduced (I assume because of no crossover), a bit of "magical twinkle" in the higher pitches seemed to be missing/less clear. I could click back in/out of PA and in PA the high pitched synths just had a tad more magic/clarity. It was odd! So I played around with the speaker distrances, which previously were:-
Center: 2.49m
All others: 2.7m
And set them all to 2.7m, and voila, non-PA sounded the same as PA (as regard that high pitch clarity).

Very odd! But I flicked between the center being the same distance as all the other speakers, and the short distance, and there was definately a difference!

Figuring the distance is all but pointless (as for most of what I watch we're talking ARC from TV to AMP) I set all distance to the min distance (0.03m), and it continued to sounds the same (better).
 
hornetstinger said:
Leave distances alone
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As I said there was a distinct bit of clarity in Pure Audio in the higher frequencies (in a 5.1 stream), and I deduced the only setting that PA could be affecting for that difference was applying speaker distance or not. And indeed playing around with the center speaker distance from 2.49 to 2.7m I'm certain made no-PA sound like PA.

Given that, so now all speakers were 2.7m, what's the difference between 2.7m and 0.03m (the minimum) given virtually everything I watch is TV -> ARC -> AMP?

What am I missing?

ps: I've always found speaker distances a bit of an odd notion, given you can sit in a dozen places in a room, and speaker distance will be difference for each. ie: So any defined for the amp are nothing more than a best average.
 
goonerfromlag said:
Any chance of raising the tv height with a stand so that a 905 centre speaker can sit out in the open?
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Physically? Yes. Esthetically? No :(

Really wouldn't be my ideal solution...

I contacted a couple of local wood work related companies to see if they would have a large lathe or sander that could easily take off 3-4mm from the bottom of a 905 case, but not heard back. Suspect CV19 isn't helping!
 
Well, an update to this saga.

To recap, I have Mordaunt Short:-
All through an Onkyo 646 amp.

I was considering upgrading all the speakers, but in the end various advice and help definately tightened up the sound of the existing speakers and simply left me wondering then if replacing the small center 304 with a bigger 905 (sort of to match of 902 fronts) would help.

I finally got one (second hand of course) and after a lot of player films and music, came to the conclusion there was minimal difference, and if anything I'd have to say my existing smaller 304 was a tad clearer/tighter to listen to, especially for dialog. So, given the 905 would require messing about to fit in my current config, I'll stick with the smaller 304.

note: There is the potential that the second hand 905 isn't working at 100% potential I guess...
 
lucid said:
Accepting the possibility that the 905c is in some way broken but setting that idea aside for a moment; the larger centre should be more capable, but it requires some work to integrate it. The smaller centre with less bass will be easier to integrate but ultimately more limited in the frequency range. A lot depends on the room and the positioning of the speaker.
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Well, the 905C sounded fine. ie: It was very very close to my existing 304. So while it make be damaged/warn, it certainly was pretty functional.

I had a hard time telling the two apart - I was swapping between then in just 5s or so at times and listening to the same audio - but at times the smaller 304 definately just sounded cleaner, especially with dialog in movies. With the 905 the dialog didn't sound as fixed/clean, if that's an appropriate description. But it was very close...

I'm sure the 905 would probably be more capable at high volumes, but again I tested at as loud a volume as I'd typically ever use, and that's where the 304 was the same, or possibly better to my ears.

Note: It's a 905C, not a 905Ci. But I believe they're basically identical.

ps: Thanks again for your help ealier in the year configuring the existing set up! Helpful!
 
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