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Mr Pig
19-02-2011, 12:32
I could use some advice on structural subsonic feedback.

My turntable and speakers sit very close to each other, they fit into the room nicely that way. Moving the turntable would be possible but I'd rather avoid it. Not ideal I know but up until now it's not been an issue. It is now!

Recently I added two Mana Sound Bases under each speaker stand. Not important here except for the fact that it has lowered the resonant frequency of the speaker support. At high volume, subsonic noise from the turntable is now setting up a nasty feedback loop. The bass driver oscillates at very low frequency, sets the stand off at the same frequency, the vibration is passed through the floor and up the turntable stand. The LP12 suspension can't deal with vibration at this low a frequency so it's setting off oscillation in the deck that's very audible. In fact, play the right record loud enough and it'll chuck the stylus clean out of the groove!

So that's the problem, how do I fix it.

If it comes to it I'll move the turntable, that would solve it. However if I can get around it some other way I'd rather do that.

What I have considered is shoring up the floor from underneath, I do have limited access. In fact I've already put 'soldiers', vertical legs down to the solum/ground, under the main racks to help with footfall and was considering more/better ones to further increase the stiffness of the floor. I also thought about adding mass to the floor, basically by bolting stuff to the joists, but I don't know if I could lower the resonant frequency enough that way. The floor is already holding a few hundred kilograms of stuff after all.

Any other thoughts or ideas would be very welcome :0)

http://theartofsound.net/forum/picture.php?albumid=74&pictureid=446

Reid Malenfant
19-02-2011, 12:35
What no subsonic filter in your amp or phono stage? :scratch:

That'd solve it in one go..

Mr Pig
19-02-2011, 12:37
What no subsonic filter in your amp or phono stage?

Nope. It would indeed solve it but I don't know how it would effect the sound.

Ali Tait
19-02-2011, 12:40
Add something to the stands to change the resonance frequency?

flapland
19-02-2011, 12:40
OK, I will be first to suggest the most obvious possible fix..... wall shelf. With all of those supports though I suspect this is going to be a tough nut to crack without relocating.

Another obvious one and might able confirm if its ground or airborne vibration and that is to run the LP12 with its lid.

Now I don't claim to be a expert in any of these matters but my twopence worth to start the ball rolling.

Reid Malenfant
19-02-2011, 12:41
A high pass filter at 15Hz with 18Db/octave rolloff i'd have thought was pretty much standard issue on any phono stage, frankly i'm amazed :eek:

Not fit for purpose, this is a universally recognised problem & the filter is the solution ;)

Macca
19-02-2011, 12:45
A high pass filter at 15Hz with 18Db/octave rolloff i'd have thought was pretty much standard issue on any phono stage, frankly i'm amazed :eek:

Not fit for purpose, this is a universally recognised problem & the filter is the solution ;)

:lolsign: It's not 1975 anymore, Mark!

Reid Malenfant
19-02-2011, 12:48
Sorry Martin but records are still the same chap & decks aren't any different, they still spin records & are susceptible to vibration which is where the subsonic filter comes in :eyebrows:

Macca
19-02-2011, 12:52
Sorry Martin but records are still the same chap & decks aren't any different, they still spin records & are susceptible to vibration which is where the subsonic filter comes in :eyebrows:

True, but what current amp or pre-amp has one? I've had the problem in the past that's why I intentionally bought a house with a solid concrete floor:eyebrows:

What about paving slabs under all the stands? I know it's not pretty but need s must...

Reid Malenfant
19-02-2011, 13:42
Colin, i'd suggest you try & add mass to the turntable stand or the speaker stand to raise the resonance frequency. Looking at it i'd go with the TT stand for starters as that'll have less mass & looking at the pic it looks a little bit more precarious than it's speaker counterpart ;)

Mr Pig
19-02-2011, 16:16
Add something to the stands to change the resonance frequency?

You could, add weight basically or 'ground' them or the speaker to the wall behind but it's probably not a good idea. Mana is designed to resonate, that's how it works. it would be a bit like attaching damping to a xylophone, you'd stop what you wanted in the first place.


A high pass filter at 15Hz with 18Db/octave rolloff I'd have thought was pretty much standard issue on any phono stage

It was quite common for minimalist amplifiers of the seventies and eighties not to have anything in the signal path that didn't have to be there. You can argue about the pros and cons but that's what they did, and that's what I have.


wall shelf.

I'd need to find a Mana wall shelf and five Sound Frames to be the equivalent of what I have here in Sound Stages. It's a solid wall though so it would work. But as I don't have the shelf or Frames, and they're not that easy to find, it's not a path I can go down right now.


Another obvious one and might able confirm if its ground or airborne vibration

It's structural. 100% sure.


I'd suggest you try & add mass to the turntable stand or the speaker stand to raise the resonance frequency

Again, you're back to the fact that you're damping down the Mana. It's designed to wobble! It's already very heavy. The open design might be deceiving, I doubt you'd be able to lift that turntable support. You've got a lot of iron in there, seven boards and two sheets of glass.


What about paving slabs under all the stands?

That might work. I don't know if it would sound better or worse but I think it would possibly kill the resonance, maybe. I don't know. What I had thought about was putting that extra weight under the floor, fixing weight to the underside of the floor. I could do that but I don't know if it would work, and it would be a downer to do it and find it didn't work.

Chris
19-02-2011, 16:36
Something similar has happened to a mate who has just bought a Linto to replace his Black Cube SE. Only he can´t use it because of his laminated floor. The cube has a filter but the Linto hasn´t. Curiously enough, his deck is on a Mana Rack too. He´s working up the courage to tell his missus he will have to use a wall shelf.

Welder
19-02-2011, 16:40
If there wasn’t this problem before then get rid of the Mana shelving would seem the obvious answer.

Subsonic frequencies are almost impossible to damp out in a domestic setting and if your system shelving relies on isolation rather than mass I cant see you sorting this out without major structural work. Subsonic will travel through slabs under the speakers in all likelihood unless you add massive amounts of weight to the cabs and stands.
I have always mounted sprung sub chassis record decks on solid walls in the past for exactly this reason. A decent pair of speakers with low bass capability will have suspended flooring singing along every time.

Spreading the speaker feet across the joist can help (it did a bit where I live anyway) but the floor still vibrate but I don’t have a record deck to worry about.

I feel for you Colin. The vibration here almost brought me to tears when I first moved in.

Stratmangler
19-02-2011, 16:53
How about making sand boxes as the bases for the speaker supports ?

http://www.tnt-audio.com/clinica/sandblaster_e.html

You can change dimensions about to suit, so it's possible to make some relatively attractive bases.
Don't start about aesthetics - you've got several hundredweight of angle iron there, and it don't look pretty :lolsign:

BTH K10A
19-02-2011, 17:43
Do the new Mana speaker stands solve more issues than they cause? If do then ditch the Mana's and either go back to your previous setup or maybe try a demo of some Townshend stands.

YNWaN
19-02-2011, 18:34
it has lowered the resonant frequency of the speaker support.

I would place a different interpretation on the changes - I don't think it has lowered the resonant frequency, it is resonating in tune with some frequencies (probably 40/50Hz) - and your turntable stand is resonating in sympathy.

If, as you say, the Mana is intended to resonate, then it is, by definition, adding colouration - you have now added so much of that colouration (frequency boosting) that the system cannot cope. Adding weight won't help.

To be honest, I would remove most (if not all) of the Mana - certainly all the 'sound bases; from both the speaker stands and the turntable stand.

Ali Tait
19-02-2011, 18:44
Is it a suspended wood floor? If so, maybe if you.can get under the floor, cut some lengths of say fence post to be a tight fit from the ground to the underneath of the wood floor under the rack and the speakers. This may help to channel the vibration down into the ground rather than along the floor. May not work, but it would be cheap to try.

Mr Pig
19-02-2011, 19:24
Subsonic frequencies are almost impossible to damp out in a domestic setting. Subsonic will travel through slabs under the speakers in all likelihood unless you add massive amounts of weight

This is kind of what I thought. The amount of mass needed to stop the floor vibrating at those frequencies would be huge.


cut some lengths of say fence post to be a tight fit from the ground to the underneath of the wood floor under the rack and the speakers.

I've already done that, years ago, under the racks to tackle chronic footfall. It was hard to walk over to the turntable when it was playing without it skipping. It did the trick there but I don't know if more in different places would help with this. As you say, it's cheap to do so I might try it anyway.


Do the new Mana speaker stands solve more issues than they cause?

More Mana just improves the sound over all. This issue is a fluke result of having that speaker and the turntable so close together on a wobbly floor.


If the Mana is intended to resonate, then it is adding colouration - you have now added so much of that colouration that the system cannot cope. To be honest, I would remove most (if not all) of the Mana.

I don't think you've ever used Mana? I don't think you understand how it works. The more you add the less coloured the sound is. I don't want to remove any of the Mana. It is critical to how the system sounds, it is quite frankly fantastic!

BTH K10A
19-02-2011, 19:42
More Mana just improves the sound over all. This issue is a fluke result of having that speaker and the turntable so close together on a wobbly floor.

I don't think you've ever used Mana? I don't think you understand how it works. The more you add the less coloured the sound is. I don't want to remove any of the Mana. It is critical to how the system sounds, it is quite frankly fantastic!

I phoned a friend (who still has flat earther tendancies) on this one as I remembered he had similar issues a couple of years ago when he moved house.

He's a civil engineer so should understand resonance issues and said he threw a lot of money at the problem with limited success until he borrowed a seismic sink. The Mana racks he had are now sold.

YNWaN
19-02-2011, 19:47
I don't think you understand how it works. The more you add the less coloured the sound is. I don't want to remove any of the Mana. It is critical to how the system sounds, it is quite frankly fantastic!

Perhaps I don't know how it works - how do you think it works, please explain?

If I were in your position, I would look to reinforcing the floor both beneath the speakers and the turntable - effectively, the floor is behaving like a large sounding board (if the items share joists this does not help). What has been done in the past is to lift the carpet and glue and screw plywood to the floorboards (the underlay can be cut to accommodate).

Whatever you do, best of luck.

Welder
19-02-2011, 19:51
If you're that keen to keep the Mana racks......

You could just take up the floor underneath the rack you have your turntable on and shutter that area and fill with concrete Colin. It’s not quite as drastic as it sounds and is likely to have more benefit than all the struts and slabs. Don’t forget damp proof membrane top and bottom. Cant be much more than a couple of cubic metres of concrete.

Mr Pig
19-02-2011, 20:01
he borrowed a seismic sink. The Mana racks he had are now sold.

Mana comes up for sale so people do stop using it. However the seismic sink was around at the time I got my Mana and I remember quite a few people not liking it. People who were on the same sort of wavelength as me regarding what we wanted from a stereo. I like what Mana does so I'm in little rush to get rid of it.


Perhaps I don't know how it works - how do you think it works, please explain?

Sure, will do. Not right this second but I'll post up some stuff. To be honest, I doubt anyone knows for sure why it does what it does. Some of us have theories but the effect of the product is sufficiently large that they don't seem to cut it.


You could just take up the floor underneath the rack you have your turntable on and shutter that area and fill with concrete Colin.

You know, that is the best idea I've heard yet! Now that you mention it, I've heard of it before but I'd completely forgotten about it and I doubt I would have remembered had you not said. That would be a total fix and it's doable, it works for the situation.

YNWaN
19-02-2011, 20:08
Hmm.............

Welder
19-02-2011, 20:14
If you’re going for this Colin use an accelerator in the concrete mix and mix an ST5 if you’re buying it in ready mixed or 1 : 3 cement to ballast if your mixing yourself with accelerator.
Dig a few inches into the substrate coz its prolly loose ruble; you need solid earth underneath.
Shutter inside the earth pit you’ve dug.
Bear in mind that you’ll either have to leave a concrete top showing in the room or find a way to bond the removed floorboards to the top of the concrete.

Course, you could just chuck the lot out and move to file audio ;)

Tarzan
19-02-2011, 22:02
OK, I will be first to suggest the most obvious possible fix..... wall shelf. With all of those supports though I suspect this is going to be a tough nut to crack without relocating.

Another obvious one and might able confirm if its ground or airborne vibration and that is to run the LP12 with its lid.

Now I don't claim to be a expert in any of these matters but my twopence worth to start the ball rolling.

Beat me to it Paul:)

Mr Pig
20-02-2011, 08:07
Course, you could just chuck the lot out and move to file audio

Ha ha, indeed. But then I'd have a whole bunch of other sound quality issues that make rebuilding you house seem like a simple solution!

I don't actually use the turntable very much these days, CD is just too convenient and cheap. Was in a shop today, new LPs are twenty quid!

Thanks for the advice on the concrete etc. I've built a concrete base for a shed, same thing, different shape. As you say, the only thing that's tricky is the top. The room's carpeted so I'd need the platform to be perfectly flush with the surrounding floor. Probably not too tricky if you just cement the top but I'd rather have a board on the top to give a nice surface for the spikes.

I think I'll try the legs/soldiers first, see what that does.

BTH K10A
20-02-2011, 08:52
I think I'll try the legs/soldiers first, see what that does.

The spikes are the point of transfer of the vibration whether it's direct from the speakers or due to spl's turning your floor into a low frequency soundboard.

You could try replacing the spikes on the stands with rubber feet or use some anti LF vibration units made for industrial equipment.

Another option is to add an additional (non Mana) isolation platform under the deck.

Ammonite Audio
20-02-2011, 09:13
If you're that keen to keep the Mana racks......

You could just take up the floor underneath the rack you have your turntable on and shutter that area and fill with concrete Colin. It’s not quite as drastic as it sounds and is likely to have more benefit than all the struts and slabs. Don’t forget damp proof membrane top and bottom. Cant be much more than a couple of cubic metres of concrete.

Be prepared to be disappointed with your music if you do this, even though it seems a logical thing to do. I know two people who have done the same thing, and it totally ruined the overall listening pleasure that they had before. Sounds daft, but having different structural materials in the floor of your listening room is a bit if a no-no. The reasons for this effect may be found in terms of differential mass, characteristic impedance, stiffness etc. Analyse at your pleasure or peril.

One obvious question - is the suspension of your LP12 set up correctly, particularly the arm lead dressing? If the arm lead is particularly stiff or 'shorting' the suspension, that could be making matters worse.

Marco
20-02-2011, 10:10
Hi Colin,

Oh no, I feel guilty now for selling you the extra bases! :doh: :eyebrows:

This sort of thing can happen sometimes, as often when you improve areas of your set-up (and I don't doubt that when you solve the feedback problem, you will hear a noticeable improvement with your system, if indeed you can't already hear aspects of that), it has the knock-on effect of revealing deficiencies elsewhere.

I've had to deal with that challenge throughout the journey at arriving at the system I have now. It's the only way of making progress and moving towards genuinely better performance. The irony is that sometimes you have to go backwards (temporarily) in order to move forwards......

As for removing the Mana, I had to chuckle, as only those who've never heard its (rather astonishing) effect at allowing a system to perform optimally, would suggest such a thing! ;)

So what would I do in your situation?

Simples..... Just swap your stacks around, so that the stack your T/T is on is as far away from the speakers as possible - then revel in the musical joys of having phase 3 under your Briks! :)

I certainly wouldn't get involved in the massive upheaval of what else has been suggested, not only for the inconvenience factor, but because after having gone through all the rigmarole, I don't think the end result will sound better, even if it cured the feedback problem.

Either that, or get rid of yer ol' bouncy fruitbox and buy a Techy ;)

My T/T (on phase 16 Mana) isn't much further away from one of the Lockwoods, which are about three times the size of your Briks (and reproduce huge tracts of intestine-rearranging bass that like wouldn't believe :eek:), and I have zero problems with feedback!

Anyway, dude, I hope you get it sorted to your satisfaction A.S.A.P :cool:

Marco.

BTH K10A
20-02-2011, 11:13
Hi Colin,
As for removing the Mana, I had to chuckle, as only those who've never heard its (rather astonishing) effect at allowing a system to perform optimally, would suggest such a thing! ;)
Marco.

But Marco, the earth is round (ish) :lol:

Welder
20-02-2011, 11:13
I have heard that the Mana platforms can do some remarkable things, but I must admit I haven’t heard a system using them.
I don’t know if this is silly or not, but what happens if you add another Mana tier?
Regarding Hugo’s concern. I would have thought that as long as the concrete plinth was physically isolated from the rest of the floor (cork surround between plinth edge and floorboards) and given it’s a relatively small not central area, the floor resonances wouldn’t change that much.
Anyway Colin, I hope you get it sorted. It’s an interesting but frustrating issue which helps demonstrate the drastic effect the listening environment can have sound.

Mr Pig
20-02-2011, 11:20
Be prepared to be disappointed with your music. having different structural materials in the floor is a bit if a no-no.

Interesting. I've never heard that before. Certainly, I prefer the sound of a wooden floor to a concrete one and Mana sounds better on wood. Especially just one or two levels of Mana which can sound frankly nasty on concrete.


is the suspension of your LP12 set up correctly

It does seem to be although I have thought about looking at it. I don't see it making any difference though. The movement is just too large and in the wrong direction for the suspension to deal with. You might be underestimating how much these bass drivers are moving, it's a lot, well over an inch anyway. And it's very low frequency, below 20Hz. It's pretty impressive! In a worrying kind of way.


As for removing the Mana, only those who've never heard its effect would suggest such a thing!

Quite. It was never an option.


Just swap your stacks around, so that the stack your T/T is on is as far away from the speakers as possible

Yes, I'm going to try that but it's not much further away. It might reduce the problem but I doubt it will eliminate it. It's not just the audible effects on the turntable, the huge bass driver excursions can't be good for them and they'll be zapping amplifier power. If swapping them around does work I'd like to track down a few Sound Stages or Sound Frames so that I can take the Sound Table out of that pile and reduce the hight of it. Although it's the perfect hight for changing records! ;0)


Either that, or get rid of yer ol' bouncy fruitbox and buy a Techy

I've got two piles of Mana, I could get two of them and be a super-cool DJ! ;0) I doubt a standard Technics would sound better than my LP12 and I can't afford to spend the thousands necessary to make it do so. I reckon that unless you put most of the working parts in the bin the Technics is little more than a good sounding DJ deck.

Mr Pig
20-02-2011, 11:47
but what happens if you add another Mana tier?

If I told you you probably wouldn't believe me! ;0)

When I first had Mana it was on a concrete floor and I only had a Mana rack and Reference Table for the turntable. I didn't have any of the flat platforms underneath that you can see in the picture. I bought one and was stunned by what it did but it made sense. The stand was now sitting on a nice wooden platform instead of the concrete, like sitting on a suspended wooden floor effectively, so it stood to reason that it would sound different.

Another Sound Stage, as those platforms are called, was added under the other equipment rack, same result, then I got another one for under the turntable. Now, it already had one, and it had replaced a concrete floor, so I was not expecting that much from a second one. It was just slightly more of the same thing after all.

The improvement was just as big as fitting the first one! And every Sound Stage I've added has done exactly the same thing. It's real head scratching stuff but Sound Stages are just amazing.

What happens as the levels increase is that the sound gets clearer, sharper, more natural sounding and more dynamic. Just a LOT better. It's not subtle. It's worth noting that I use an old Micromega CD player, the cheapest one they made, but it wipes the floor with every other CD player I've heard except other CD players on Mana ;0) The LP12 sports an RB300 and DL103, similar story.

Last year I visited a guy who had a REALLY expensive 'round earth' system, I think it was about sixty-grands worth. I was quite exited about hearing it, he'd talked it up big time. After about two minutes I knew I had been a wasted drive. When I got home the first thing I said to my wife when I walked in the door was "If someone stole my system and replaced it with that one I'd be really pissed off". Two other people who rated his system also heard mine and they both thought it was better.

And it's just down to the Mana, it's astonishing.

Marco
20-02-2011, 11:52
Hi Colin,


I doubt a standard Technics would sound better than my LP12 and I can't afford to spend the thousands necessary to make it do so. I reckon that unless you put most of the working parts in the bin the Technics is little more than a good sounding DJ deck.


Lol... I know, my remark was very much tongue-in-cheek! Apart from anything else, your LP12 works, synergistically, very well in your system. It's a very good sounding LP12 (you do know what you're doing there), even though its made up of 'bits'! ;)

I still remember the flack I got on the Mana forum for preferring your LP12 to Devil-boy's, despite his being higher spec and on more Mana :eyebrows:

Anyway, defo try moving your stacks around before doing anything else, and when you're at it, try and put as much distance as your set-up will allow between your T/T and the 'offending' speaker. Only if that doesn't work, entertain the notion of filling floors, etc.

TBH, if it were me, before doing any of that I'd be on the look-out for a Mana wall-shelf (preferably a Reference one), and then use all your existing Mana to max-out the electronics......

Marco.

Welder
20-02-2011, 12:09
“If I told you you probably wouldn't believe me! ;0)”

Oh I don’t know; don’t let my objectivist rep fool you. I’m just tight and generally cynical.

I have experienced some very strange effects regarding equipment placing and support.
When I did have record decks I spent considerable time and trouble building a wall mounted isolation platform that used suspended 10mm thick glass shelving in an epoxy filled square section steel frame not unlike the Mana shelves.

John Watson was fairly well known in the biking circles I knocked about with back in the day and quite a few I knew back then welded up Watson copies ;)

Mr Pig
20-02-2011, 17:02
I remember the flack I got for preferring your LP12 to Devil-boy's.

Must've been after my time. I only heard his system early on when the only Mana he had was a wall shelf, it didn't sound very good then. I assume it was pretty great with the ATC 100s and it all set up properly but I never heard it.


John Watson was fairly well known and quite a few I knew back then welded up Watson copies

Not hard to do, it's all quite straightforward. I'm sure you know that Marco has made a lot of Mana clones which he says work perfectly although I think he used MDF boards, the originals are chipboard.

There are a few features of the design which are quite important although it's not obvious. You could get it wrong.

Welder
20-02-2011, 18:18
I’ll be sticking to my converted tea trolley for the foreseeable future……………….
Mind you, I’ve already started modding that :lol:

No i idn't know Marco knocked up Mana replicas....good on him ;)

Mr Pig
20-02-2011, 22:09
No I didn't know Marco knocked up Mana replicas.

Oh right, I thought it would be common knowledge, with this being his forum etc. As you can't buy them any more I guess it's the only way to get them other than hunting for used ones. It's a real shame they're out of print, it would be great if someone started making Mana again.

BTH K10A
21-02-2011, 06:49
Hi Colin,
I still remember the flack I got on the Mana forum for preferring your LP12 to Devil-boy's, despite his being higher spec and on more Mana :eyebrows:
Marco.

Marco has cracked the problem. ;) Less Mana is more! :lolsign:

Seriously though, I doubt that adding any more Mana stands will resolve the problem and nor will moving equipment due to the wavelengths involved. You may need to bite the bullet and consider adding some heretic technology to you system. :)

Yiangos
21-02-2011, 13:26
Colin,not quite sure about this but i believe once you have a subsonic problem,it really doeasn't matter where your turntable is in relation to the loudspeakers.Subsonic frequencies are everywhere inside the room and more-or-less at the same strength.
I quess,one solution is to place the turntable on a air-suspension platform but then again
i can't be 100% that it will work.

theophile
26-02-2011, 02:26
I have used a couple of 'ball and cup' type footers under glass and though I never had a footfall problem in my house,I like what they do for the sound.

Rather than have the cups machined,I used doorknobs(3) and 5/8 th inch steel balls.

I don't have a photo.The thumbnail photo is similar to the type of knob I used.Any of those ones with a 'dish' in the knob.

Mr Pig
26-02-2011, 09:24
It really doesn't matter where your turntable is in relation to the loudspeakers. Subsonic frequencies are everywhere inside the room

I don't think my issue follows the normal pattern. What I have here is what's called sympathetic resonance, where two things resonate at the same frequency and each acts to reinforce and amplify resonance in the other.

Both the speaker, on it's little pile of Mana, and the turntable on it's stand can wobble at the same very low frequency. The wobble is picked up my the cartridge cantilever, amplified and the massive speaker movements dump this same frequency back into the stand for the whole chain to start over.

As a quick fix I've swapped the turntable and CD player around. The turntable is now on a shorter, heavier Mana stand which wobbles much less and at a higher frequency. No feedback. The downside being that the turntable does not sound as good but it's a working solution until I come up with something.

Just to recap. Removing the Mana is not an option. It is not there for its looks, it's an active part of the system and contributes far too much to be removable. Putting anything in between the turntable and the stand is not an option because it would effect the interaction between the two and almost certainly wouldn't work anyway.

Thank you all for your ideas and advice :0)

YNWaN
26-02-2011, 11:56
I agree with your summation of the issue.

I had thought that I had made much the same suggestion, as the one you have now adopted; unfortunately, you seemed quite offended that suggestion at the time.

Mr Pig
26-02-2011, 14:55
I had thought that I had made much the same suggestion, unfortunately, you seemed quite offended that suggestion at the time.

Not at all, your interpretation of the energy transfer mechanism was fine. I just picked up on your ignorance of the product when you concluded it added colouration and should all be removed.

Marco
27-02-2011, 11:13
Hi Colin,

Glad you've sorted out the problem (of sorts). I thought that swapping your stacks around (or rather the sources on them) would work.

For me, your best solution would be to find a Mana wall shelf (I'm sure it's a case of seek and ye shall find) and put your LP12 on it. If you can find a Reference wall shelf, then so much the better.

I suspect that any loss in performance from the loss of 'phases' would be made up for by the improved isolation gained by wall mounting - and you can then 'phase-up' your electronics, I'm sure, to spectacular effect... :cool:

Marco.

Mr Pig
27-02-2011, 13:08
The turntable is, or was, on Phase Eight so I think dropping down to just a wall shelf would be a big drop in quality. It would be better though but I would only do it if I could find some Sound Frames to use. I'd like some Sound Frames anyway but they're not very common.

Wall shelves are good though, turntables really like them.

greenhomeelectronics
27-02-2011, 14:20
Sorbothane feet have always done the job for me.

theophile
27-02-2011, 14:40
Sorbothane feet have always done the job for me.

Wow,I don't know what I'd do without my flesh and bone feet.(Sorry).