My 3 way Lenehan ML2 Limited

[rawl99]

I see what you're saying, I just think that it makes sense not to ignore theory and the balance of evidence. I don't doubt these systems sound great with blankets, but they can obviously sound sound quite a bit better. And they probably sounded great before thousands of dollars were spent on upgrading capacitors and cables etc. Mario seems happy to spend a lot of hours listening for improvements with these things, why not with passive treatment? Spending $150 on well engineered passive treatments, at least trying before buying, might be a smart thing to do is all I'm saying. He was asking what he might do in lieu of a blanket, I'm just offering what I think most acoustic professionals would advise.

 

I do have first hand experience blankets, but I gave them up a long time ago, along with the egg boxes.

Bd

Now that you have expresed your thoughts in what seems a reasonable and helpful manner I understand more clearly where you are coming from.

Your first post re this matter was quite emphatic that in your (presumably extensive since you write with a tone of significant authority) experience the blanket is a useless approach to a problem that is virtually non-existent.

"I also can't see a tv being much of a problem, or a blanket being very effective. Firstly, a typical wall isn't really any less reflective than glass, and secondly anything that breaks up the huge flat surface of the front wall will usually only help. Thirdly the space the tv occupies isn't typically over the front wall first refection points (unless the tv is maybe 100" wide), and fourthly, if you want to add absorbtion anywhere its best to do it with something much thicker than a blanket, otherwise you attenuate mainly the very top end and risk a fairly lifeless sound."

So if you 'can't see a tv being much of a problem, for all the reasons you itemize above, then why would you endorse Grimmie's approach? Would you not suggest that his is an overkill solution to the virtually non-existent problem???

" I still can't see it being 'very' effective. If I paid a pro to come out and he just threw a blanket on the wall I'd be surprised, wouldn't you? Its no more difficult to get proper acoustical foam absorbers or diffusors and hang/unhang it over the tv with S-hooks, like Grimmie does. People also use egg crates to supposedly good effect, should we also not suggest something more effective…? "

I think it goes without saying that a 'professional' consultant would not suggest a blanket. They may be surprised by the effectivess of such a simple solution however. I used 2 of the mink blankets doubled over giving a thickness around 60 or 70mm which is not too much different to a 'proper' acoustic material. So, good enough for the job?? Have a listen and decide.

If we get an audio professional out for advice I am pretty certain that he/she will tell us that our home brew cables could easily be replaced with something more effective, as could our home-brew dac, transport, valve amp, and in a lot of cases speakers as well etc etc etc.

Will they be more effective? Maybe, maybe not?

All I am suggesting is that what is considered 'professional' advice is not always quite as good as you may imagine.

And each individuals perspective of what is good enough as a given solution will vary from a sonics and aesthetics viewpoint.

All of the best-sounding systems I have heard have had a lot of home-brewing going on and have not been assembled by a professional utilising commercial gear. Some of the components may have started as commercial offerings but in their original state they no longer remain.

You may be very surprised by some of the design approaches that have come out of putting a cushion or two in the right place, or a piece of foam.

I really can't see Mario getting a professional to come over and measure his room. He strongly seems to me to prefer to do it himself. If he were to go down the room measurement/treatment pathway I suspect he would gather the bits and doit himself.

Cause then we get that ugly question of which measurement is better.........

Rawl

[b.d]

Reasonable post Rawl, I might have stated myself a bit strongly, but I didn't go as far as to call the approach "useless". I don't really feel like an authority even if I've often been there and done that, but I do get frustrated by what I see as a generally less than thought out approach to this hobby. A blanket may work, but what are these guys putting at the points of first reflections, more blankets, nothing, not even experimenting with absorption vs diffusion? To me this is basic hifi 101 stuff, and it always puzzles me the seeming lack of importance the vast majority of SNAers give to room acoustics (along with living with different speaker technologies which Mario seems equally unwilling to experiment with), especially people who like to experiment with their systems in other regards. For some reason acoustic treatments just don't seem to attract the usual cultish followings.

[rawl99]

Reasonable post Rawl, I might have stated myself a bit strongly, but I didn't go as far as to call the approach "useless". I don't really feel like an authority even if I've often been there and done that, but I do get frustrated by what I see as a generally less than thought out approach to this hobby. A blanket may work, but what are these guys putting at the points of first reflections, more blankets, nothing, not even experimenting with absorption vs diffusion? To me this is basic hifi 101 stuff, and it always puzzles me the seeming lack of importance the vast majority of SNAers give to room acoustics (along with living with different speaker technologies which Mario seems equally unwilling to experiment with), especially people who like to experiment with their systems in other regards. For some reason acoustic treatments just don't seem to attract the usual cultish followings.

Thanks Bevan,

I was trying to communicate a point without being nasty or offensive so if my wording came across that way at all I do apologise.

Not intended at all.

From your posts over the years I do get the impression that you have experimented with quite a few different things.

I completely understand what you mean by HiFi 101 re the room.

I have quite extensive treatment in my rrom which was set up by ear and then checked by measurement to see what the measurements showed. In essence, the ears were good in that the measurements appeared to concur with the aural findings.....in terms of gross items. The fine nuances, measurements shed no light on these nuances whatsoever IMO.

The little game of first-reflection points(side wall, ceiling and back wall), absorption vs diffusion etc is fun and can yield some really interesting and confounding results can it not. My first reflec point is a combination of absorption and reflection depending upon the freq hitting it and changing it to absorption only has significant mpact on the perceived soundstage. As does the rear-wall diffusion/absorption as I mentioned in earlier post.

What I am yet to understand is what is it that I am supposed to measure to KNOW from the measurements that these improvements/changes are occurring.

A lot of folks I chat with have no issue with measurements but have some doubt/difficulty regarding the association of what values of what measurement parameters mean that something sounds good.

I have asked that question repeatedly across multiple forums and consistently get the response that measurements are critical but no correlated data to show what parameter should measure at what value to ensure great sound.

And that I think is the point of view that Mario comes from.

He and I have had shared listening experiences in front of a number of superb systems using horns, stats, full-range etc etc and both agree that they are magnificent.

But for Mario's room these approaches will not work and he does not want to burn up the time and energy to go through all the development to get to a point slightly better than where he is now.

Perhaps......he has done all that and just likes to enjoy the music now - the fruits of his labours.

I disagree quite strongly that the room treatment thing does not attract a cult membership. It is one of the most hotly argued topics on this forum....Eg. " room plus speaker is 90% of the sound"

I personally think this is utter tripe. My experiences do not in any vague way at all concur with this viewpoint. But hey, each to their own.

Rawl

Edited December 15, 2013 by rawl99

[b.d]

No worries, no offence taken.

 

The treatment advocates can be pretty vocal, but to me they seem to be have relatively well reasoned and empirically supported positions, at least compared to most other things people swear by in this hobby. And it seems the benefits of acoustical treatment are obvious enough that nobody ever feels a blindfold is needed. I still feel though that they get relatively short shift, maybe because they seldom get glowing review in the mags, don't inspire brand loyally, don't come in shiny boxes or offer much pride of purchase…I don't know.

 

Re measurements, just had someone PM me a few minutes ago asking if I could offer advise on their standmount setup - I suggested bass trapping the **** out of the room, trying speakers further away from the side wall, diffusers etc etc,  and only suggested a using a mic to make the process of quicker, to see what gives the most linear bass. I said it could be done without a mic but that it'd take a hell of a lot longer to give each position a fair go. And moving the speakers away from boundaries, if you look at the evidence of Tool/Linkwitz and aim for 6-10ms, well you might want to use a measurement too, if only a tape measure. And is you add subs and want to get phase and amplitude optimised, measurement help, are easy enough to read, and do correlate with sound quality. I don't think you even need get into RT60 times and all the other measurables. I think most importantly though, a microphone is a learning tool for curious minds that help one understand, across a number of speakers and arrangements, how amplitude and phase differences translate to the differences we hear between setups, which I think can be quite an effective antidote against superstition and voodoo.

 

If Mario is happy with his setup and no longer wants to tweak or spend money and just wants to listen to the music, seriously I'd be the first to congratulate him and happily leave him be.  

 

Cheers

B

[Pops110]

Reasonable post Rawl, I might have stated myself a bit strongly, but I didn't go as far as to call the approach "useless". I don't really feel like an authority even if I've often been there and done that, but I do get frustrated by what I see as a generally less than thought out approach to this hobby. A blanket may work, but what are these guys putting at the points of first reflections, more blankets, nothing, not even experimenting with absorption vs diffusion? To me this is basic hifi 101 stuff, and it always puzzles me the seeming lack of importance the vast majority of SNAers give to room acoustics (along with living with different speaker technologies which Mario seems equally unwilling to experiment with), especially people who like to experiment with their systems in other regards. For some reason acoustic treatments just don't seem to attract the usual cultish followings.

Hi Bevan,

I would love to try some acoustic treatment in my room, as I imagine the majority of us would.

But the reality is most systems are in multi purpose rooms, lounge rooms, family rooms etc. it's just not practical or possible. There is no way my missus would let me put up treatments in any shape or form.

I have tried the doona over the tv and behind my right speaker as it's closer to the fire place, it makes quite a difference. My room is quite bright and it seems to tame this quite a bit.

But in everyday life I can't be bothered to move stuff off the mantle and set the doonas up. I get very little time to listen these days, so I just put up with my rooms shortfalls and put my feet up and listen and enjoy.

Cheers Dave.

[Once was an audiophile]

 (along with living with different speaker technologies which Mario seems equally unwilling to experiment with)

Oh B.D i travel the country and hear different speaker technologies like axiom 80,horns and panels due to room restrictions  to cater for such speakers i enjoy other peoples journeys.If i had the required space a horn system with valve amplification would be one of my first choices something like lanche plasma guy built or Tax's system.

When you get back to Perth your welcome to come over with a microphone and measure if you improve the emotional connection i will be the first to post and recommend your knowledge on sna.

Edited December 15, 2013 by kajak12

[hochopeper]

Since I sort of kicked off this tangent to the thread with my comment about not being terribly concerned about treatments for TV/window between speakers ... I'd like to add a few comments. [and rectify the appearance that I've pulled a troll-like move by making a brash statement then disappearing]

 

My point really starts off with  exactly what  b.d. just mentioned, except that he mentions things in terms of how hearing has been historically understood .... the 6-10ms that Toole focused on has seen some more research in recent years. His research, from what I understand is the impact of an individual reflection. In recent times it appears that research indicates the impact of reflections is actually the sum (integration) of all reflections in the room within a window that is much longer than Toole investigated (50 or 60ms from memory, I'd have to look it up for exact numbers). 

 

The time period for reflections indicated then becomes longer than the dimensions of almost all domestic living rooms. 

 

So we are left to look at:

 

1. total reverb time vs freq RT60 / RT20 or whatever.

2. rooms diffusivity (is reverb spatially constant - similar as your move around the room)

3. early reflections from directions that are perceptually detrimental to the sound (we need to understand how these are created and determine the best method to address them)

4. mix of surfaces around the room with different absorption coefficients 

 

With all that in mind lets look at the case of a ML1 with a TV wall mounted behind and in the middle. The TV screen is typically plastic (most aren't glass these days as some have suggested earlier) plastic vs gyprock acoustically isn't terribly different. That far off axis what is the spectral make up of the sound? Well, probably not much in the top few octaves, I'd expect. So there isn't even a lot of high freq to be absorbed? So my comment is based on my opinion that the reflection from the TV will be only a very minor part in the make up of the reflected sounds observed at the listening position. It is possible that the reflections from the TV are 2nd, 3rd, 4th reflections and the reflections being absorbed are hence towards the later end of the window of 'early' reflections.

 

This is not to say that the doona on a TV will have no effect. Without knowing more specifics I'd not be suggesting an alternative to Mario. But my intention was that what Mario has experienced in his room might be better addressed in a different way in another room so Mario's suggestion to ljmac that the window between his speakers was a problem isn't necessarily a concern as the experience in Mario's room might not translate well to other rooms.

 

 

 

Cheers,

Chris

Edited December 15, 2013 by hochopeper

[rawl99]

No worries, no offence taken.

 

The treatment advocates can be pretty vocal, but to me they seem to be have relatively well reasoned and empirically supported positions, at least compared to most other things people swear by in this hobby. And it seems the benefits of acoustical treatment are obvious enough that nobody ever feels a blindfold is needed. I still feel though that they get relatively short shift, maybe because they seldom get glowing review in the mags, don't inspire brand loyally, don't come in shiny boxes or offer much pride of purchase…I don't know.

 

Glad no offense taken.

I agree that the reasoning behind acoustic treatments is well-reasoned and supported. I use it extensively in the rooms I do for the obvious benefits it offers.

Interesting your comment about glowing reviews. Ethan Winer's products have a very solid following and are extremely highly respected. He is a very talented and knowledgeable guy.

I think the latter part of your para is the key. Room treatments blend into the scenery if they are done well and in the majority of situations folks don't hear a before and after. They become a part of the room that 'just is'.

This does not detract from their importance however.

Re measurements, just had someone PM me a few minutes ago asking if I could offer advise on their standmount setup - I suggested bass trapping the **** out of the room, trying speakers further away from the side wall, diffusers etc etc,  and only suggested a using a mic to make the process of quicker, to see what gives the most linear bass. I said it could be done without a mic but that it'd take a hell of a lot longer to give each position a fair go. And moving the speakers away from boundaries, if you look at the evidence of Tool/Linkwitz and aim for 6-10ms, well you might want to use a measurement too, if only a tape measure. And is you add subs and want to get phase and amplitude optimised, measurement help, are easy enough to read, and do correlate with sound quality. I don't think you even need get into RT60 times and all the other measurables. I think most importantly though, a microphone is a learning tool for curious minds that help one understand, across a number of speakers and arrangements, how amplitude and phase differences translate to the differences we hear between setups, which I think can be quite an effective antidote against superstition and voodoo.

Fair call. In a significant way your advice comes from empirical results though does it not?

The gent (presumably) you shared this information with does not have the correlation knowledge you have but your advice will help him achieve great results very quickly.

But this is only in the bass that you really are referring to.

There is a GREAT deal more to music than just the bass linearity/integration.

And it is in these finer areas where I find the measurements to be less useful.

As I have said often before. Measurement tools are absolutely awesome for sorting out the gross factors.

When it comes to the fine factors of:

Which piece of wire sounds better in a given application,

Which resistor gives the most natural presentation,

Which capacitor on the power supply gives the most 'life' and ' engagement' to the musical presentation.....

Etc etc

Then I find measurements to be all but useless.

 

If Mario is happy with his setup and no longer wants to tweak or spend money and just wants to listen to the music, seriously I'd be the first to congratulate him and happily leave him be.  

 

Cheers

B

Kin oath Bevan. We can only be envious.

Craig

[hochopeper]

As I have said often before. Measurement tools are absolutely awesome for sorting out the gross factors.

When it comes to the fine factors of:

Which piece of wire sounds better in a given application,

Which resistor gives the most natural presentation,

Which capacitor on the power supply gives the most 'life' and ' engagement' to the musical presentation.....

Etc etc

Then I find measurements to be all but useless.

 

 

Hi Rawl,

 

We're going wayyy off the topic of 3way ML2 Ltds but .... I've got some PCBs here for measurement gear that I'm working on order lists for this weekend ... the plan is to measure PSUs down to below 1uV noise ... might be able to get down to 0.2 to 0.5uV if I'm really careful. My PSUs that I am working on at the moment are mostly for digital parts of the signal chain. I'm going to build two separate high gain amps to compare the results, one of them will have a stack of BF862 jfets the other will be opamp based.

 

Chris

Edited December 15, 2013 by hochopeper

[henry218]

Hi Rawl,

We're going wayyy off the topic of 3way ML2 Ltds but .... I've got some PCBs here for measurement gear that I'm working on order lists for this weekend ... the plan is to measure PSUs down to below 1uV noise ... might be able to get down to 0.2 to 0.5uV if I'm really careful. My PSUs that I am working on at the moment are mostly for digital parts of the signal chain. I'm going to build two separate high gain amps to compare the results, one of them will have a stack of BF862 jfets the other will be opamp based.

Chris

hi Chris,

perhaps make a new thread? im sure many are interested with your future findings and discovery, including me

cheers

henry

[hochopeper]

One day Henry, once there is something to look at ... just working out the parts list at the moment ($400 or so in parts just to do some measurements ... DIY ADC, RMS thermal noise measurement circuit, two low noise amps .... ) then building then measurements etc ... don't expect anything soon.

Edited December 15, 2013 by hochopeper

[rawl99]

Since I sort of kicked off this tangent to the thread with my comment about not being terribly concerned about treatments for TV/window between speakers ... I'd like to add a few comments. [and rectify the appearance that I've pulled a troll-like move by making a brash statement then disappearing]

 

My point really starts off with  exactly what  b.d. just mentioned, except that he mentions things in terms of how hearing has been historically understood .... the 6-10ms that Toole focused on has seen some more research in recent years. His research, from what I understand is the impact of an individual reflection. In recent times it appears that research indicates the impact of reflections is actually the sum (integration) of all reflections in the room within a window that is much longer than Toole investigated (50 or 60ms from memory, I'd have to look it up for exact numbers). 

 

The time period for reflections indicated then becomes longer than the dimensions of almost all domestic living rooms. 

 

So we are left to look at:

 

1. total reverb time vs freq RT60 / RT20 or whatever.

2. rooms diffusivity (is reverb spatially constant - similar as your move around the room)

3. early reflections from directions that are perceptually detrimental to the sound (we need to understand how these are created and determine the best method to address them)

4. mix of surfaces around the room with different absorption coefficients 

 

With all that in mind lets look at the case of a ML1 with a TV wall mounted behind and in the middle. The TV screen is typically plastic (most aren't glass these days as some have suggested earlier) plastic vs gyprock acoustically isn't terribly different. That far off axis what is the spectral make up of the sound? Well, probably not much in the top few octaves, I'd expect. So there isn't even a lot of high freq to be absorbed? So my comment is based on my opinion that the reflection from the TV will be only a very minor part in the make up of the reflected sounds observed at the listening position. It is possible that the reflections from the TV are 2nd, 3rd, 4th reflections and the reflections being absorbed are hence towards the later end of the window of 'early' reflections.

 

This is not to say that the doona on a TV will have no effect. Without knowing more specifics I'd not be suggesting an alternative to Mario. But my intention was that what Mario has experienced in his room might be better addressed in a different way in another room so Mario's suggestion to ljmac that the window between his speakers was a problem isn't necessarily a concern as the experience in Mario's room might not translate well to other rooms.

 

 

 

Cheers,

Chris

Chris,

Thank you very much for that insightful and informative post.

I don't get a lot of time to read the research of 'the gurus' so I appreciate your summary.

It is very interesting that I was dismissive of some of Tooles research because my personal experiences differed so wildly from his findings that I just chose to go with my own experiences and observations; as well as my own correlation of measurement vs listening experience.

One of the most significant areas was the stuff you are discussing re impact of delayed reflection and the "effective" window being much greater than 6-10mS and more like the 50ish ( or whatever) mS. This fits in with my experiences quite wonderfully and 'tis terrific to see this research finding.

Gives me a wee bit of faith that I am not completely nuts ( or delusional. :-) )

The effect of the doonah on the TV is on the subtle end of the scale but is IME quite audible.

As to whether the sonic artifact is a first reflection or the effect of a higher order one is an interesting question.

May have to break out some impulse testing some time and see what can be observed. Doonah on, doonah off.

Kinda like the karate kid.

Ther has been some interesting testing done, as I am sure you would be well aware, on the perceived effects of front, side and rear wall absorption and the corresponding effects on perceived soundstage etc etc. From memory, often times it seems better to predominantly leave the front wall alone and concentrate on the side and rear. I experimented some years ago at length with this aspect and I pretty much leave the front wall as it is with only bass trapping in the front corners. No other absorption on the front.

Rawl

[rawl99]

Hi Rawl,

 

We're going wayyy off the topic of 3way ML2 Ltds but .... I've got some PCBs here for measurement gear that I'm working on order lists for this weekend ... the plan is to measure PSUs down to below 1uV noise ... might be able to get down to 0.2 to 0.5uV if I'm really careful. My PSUs that I am working on at the moment are mostly for digital parts of the signal chain. I'm going to build two separate high gain amps to compare the results, one of them will have a stack of BF862 jfets the other will be opamp based.

 

Chris

Chris,

Ditto to Henry. Will be VERY interested if we can correlatE PS noise spectrum to perceived listening results.

Please keep me up to date with your progress.

Craig

[Gremrock]

Bit late to this party, but I notice the arguments about the Blanket seem mostly that you could make it sound better with something else, I'm surprised nobody noticing the simplicity of it and how simple it is to pull a blanket down and throw it back over later... 

 

If it works well, stick with it ^_^

 

PS,

 

Will try the blanket idea myself, it never occurred to me