so.. whats in a Naim ?

[Deleted member 15865]

nobody asked me - if i switch on the fan - will the ceiling treatment fall down

Not as long as that tiger is watching them!

 

[mpw]

Not as long as that tiger is watching them!

Arre..U guessed my next post

)

 

[mpw]

i see some of forum members moving their speakers forward...

i am moving them backward ...

such is life

maybe every action does have an equal and opposite reaction..

subwoofer baffle now 39 inch from the tip of the absorber on the front wall

main speakers at 30 inches from the tip of the front wall..

Am wondering if there is a formula for how much the subwoofer needs to be kept ahead or at par with the mains - there should be - depends on the wavelength and the room i suppose.

Probably that's where measurement comes in i suppose

i came across this product on another forum and thought of sharing it here

DSpeaker 8033S-II - subwoofer correction system

its more expensive at Euro 350 incl postage to India - duty etc... our scope

@sound_cycle or forumers who have done this before.. - your thoughts ?? on this Vs miniDSP 2x4 ....can you chip in please.

 

[arj]

Am wondering if there is a formula for how much the subwoofer needs to be kept ahead or at par with the mains - there should be - depends on the wavelength and the room i suppose.


@sound_cycle or forumers who have done this before.. - your thoughts ?? on this Vs miniDSP 2x4 ....can you chip in please.

Most good subwoofers work best near the walls /corner and you need to micro-adjust position and controls to get the phase and timing right..

 

[kapvin]

i see some of forum members moving their speakers forward...

i am moving them backward ...

such is life

maybe every action does have an equal and opposite reaction..

subwoofer baffle now 39 inch from the tip of the absorber on the front wall

main speakers at 30 inches from the tip of the front wall..

Am wondering if there is a formula for how much the subwoofer needs to be kept ahead or at par with the mains - there should be - depends on the wavelength and the room i suppose.

Probably that's where measurement comes in i suppose

i came across this product on another forum and thought of sharing it here

DSpeaker 8033S-II - subwoofer correction system

its more expensive at Euro 350 incl postage to India - duty etc... our scope

@sound_cycle or forumers who have done this before.. - your thoughts ?? on this Vs miniDSP 2x4 ....can you chip in please.

@mpw there 2 different optimisations, which dont always work together.
the first question, where do get the best bass reinforcement and consistency? mostly for a single sub system, its a corner.

the second question (and possibly more important), how do I merge it best with my mains? Intuitively you are on the right track. ideally the wavefront of the passband sound of the sub should hit you at the same time as the mains. given that the electroni crossover is likely to introduce a bit of delay, I think keeping the sub ahead of the mains is intuitively correct. as far as integration is concerned (at the crossover frequency), I do think that the hypex has continously variable phase control from 0 to 180 degree which should addres most integration challenges along witht eh corssover controls.

happy listening

 

[sound_cycle]

DSpeaker 8033S-II - subwoofer correction system

its more expensive at Euro 350 incl postage to India - duty etc... our scope

@sound_cycle or forumers who have done this before.. - your thoughts ?? on this Vs miniDSP 2x4 ....can you chip in please.

Have not previously read up on the product.
From a very quick read of the FAQ it appears to perform tricks like what DRC such as REW, Dirac and the like can achieve. But for that price it is a one trick pony and I could not figure out how tunable it is. My initial response (and I am thinking wrt my set up and not necessarily generalizing). I am running my mains and sub full range - no bass management. A DSpeaker type solution will not therefore solve my issues with LF. The price is not very different from what I run either (and s/w pe import ke paise to nahi lagta) . So it does not pique my interest, and I would pass. I'd suggest trialling REW or Dirac v2 (the only cost will be borrowing a Umik).

As regards positioning the sub, I followed the REL manual and it was very easy - because I had a patient partner in crime, who matches my listening tastes. Do not use music with bass use pink noise instead (described here). My sub is about 2 feet from the side wall and 6 feet from the back wall. While unintended, the position is very close to the smoothest bass response at the LP I had worked out for the maggies. I have it very well integrated. The sub by itself is barely audible, and cannot be localized. For kicks I had the sub against the corner - it expectedly sounds like a wounded herbivore, it is the best possible to get the horriblest boom (I am not trying to be in r/iamsosmart territory)

ciao
gr

 

[keith_correa]

Actually, a corner is one of the worst places to position a sub - you get more output but it couples with all room modes resulting in boomy, one note bass. Other places, you get lesser output. There's no free lunch and one has to choose their poison.

 

[kapvin]

Actually, a corner is one of the worst places to position a sub - you get more output but it couples with all room modes resulting in boomy, one note bass. Other places, you get lesser output. There's no free lunch and one has to choose their poison.

Yes, corner placement may excite room modes But, i. It’s an 1/8 space so it has maximum reinforcement. And ii. It will more provide maximum consistency across the room for a single woofer setup. most probably the room nodes would need to be notched off, which is why it would be good for a sub in an HT with room correction. It is easy to conflate max reinforcement with room mode excitement, but there are 2 different aspects at work. happy to discuss this offline

 

[mpw]

Yes, corner placement may excite room modes But, i. It’s an 1/8 space so it has maximum reinforcement. And ii. It will more provide maximum consistency across the room for a single woofer setup. most probably the room nodes would need to be notched off, which is why it would be good for a sub in an HT with room correction. It is easy to conflate max reinforcement with room mode excitement, but there are 2 different aspects at work. happy to discuss this offline

@kapvin

whats a 1/8 space ?

 

[mpw]

Have not previously read up on the product.
From a very quick read of the FAQ it appears to perform tricks like what DRC such as REW, Dirac and the like can achieve. But for that price it is a one trick pony and I could not figure out how tunable it is. My initial response (and I am thinking wrt my set up and not necessarily generalizing). I am running my mains and sub full range - no bass management. A DSpeaker type solution will not therefore solve my issues with LF. The price is not very different from what I run either (and s/w pe import ke paise to nahi lagta) . So it does not pique my interest, and I would pass. I'd suggest trialling REW or Dirac v2 (the only cost will be borrowing a Umik).

As regards positioning the sub, I followed the REL manual and it was very easy - because I had a patient partner in crime, who matches my listening tastes. Do not use music with bass use pink noise instead (described here). My sub is about 2 feet from the side wall and 6 feet from the back wall. While unintended, the position is very close to the smoothest bass response at the LP I had worked out for the maggies. I have it very well integrated. The sub by itself is barely audible, and cannot be localized. For kicks I had the sub against the corner - it expectedly sounds like a wounded herbivore, it is the best possible to get the horriblest boom (I am not trying to be in r/iamsosmart territory)

ciao
gr

hi @sound_cycle

when you say you run your sub full range - means that you feed the sub with high level signals and then the subwoofer crossover settings manage the signal... am i right in thinking this way OR is the crossover at the subwoofer also Defeated / Off ?

 

[sound_cycle]

hi @sound_cycle

when you say you run your sub full range - means that you feed the sub with high level signals and then the subwoofer crossover settings manage the signal... am i right in thinking this way OR is the crossover at the subwoofer also Defeated / Off ?

yes. the sub gets the high level signal. In our experience, following the REL manual "it is best to start the Crossover control at 15 clicks from the minimum setting" IIRC we did 1 click around that. The sub crossover is active.

But the mains are also producing sound below that threshold.

ciao
gr

 

[arj]

I used 2 subs and they worked the best there. Had tried different options for several months...thankfully neither the subs nor me knew about the science so they worked very well

REL recommends subs to be placed on corners...

 

[mpw]

yes. the sub gets the high level signal. In our experience, following the REL manual "it is best to start the Crossover control at 15 clicks from the minimum setting" IIRC we did 1 click around that. The sub crossover is active.

But the mains are also producing sound below that threshold.

ciao
gr

yes - i use the same connections

 

[kapvin]

@kapvin

whats a 1/8 space ?

Space= no reflective surfaces- so either an anechoic chamber or a speaker suspended in the air far away enough to not make a difference. The speaker (defined as a point source) is radiating in a sphere 360degrees
half space= with the speaker on 1 reflective surface. typically the floor.
quarter space= 2 reflective surfaces ie junction of floor and wall or 2 walls
1/8 space= junction of 3 surfaces. ie corner.

you can model how a point source radiator behaves as It couples with one or more surface. Now coupling is frequency dependent(actually wavelength). and each boundary reinforces the signal.

This is also the reason that most speakers need baffle step compensation: at higher frequencies, the baffle acts as a plane and provides reinforcement. At lower frequencies, that reinforcement is not there and needs to be compensated. So you pretty much need to design a speaker system for where it will be placed. A fully compensated speaker System will sound boomy at the junction of one or more boundaries. And this is why some speakers need to be close to one or more boundaries to sound their best, it is because full BSC has not been applied. (It is typically applied in the crossover)

all of this is applicable to a theoretical point source radiator. In reality each speaker ( radiator) has some diameter or radiation surface, which impacts its behaviour predictably on a given baffle. That’s why we know that smaller diameter speakers drivers have better dispersion for higher frequencies, as they closer approximate a point source.

edit: sorry to hijack your thread. Happy to discuss this more offline over chat or a call

 

[mpw]

Space= no reflective surfaces- so either an anechoic chamber or a speaker suspended in the air far away enough to not make a difference. The speaker (defined as a point source) is radiating in a sphere 360degrees
half space= with the speaker on 1 reflective surface. typically the floor.
quarter space= 2 reflective surfaces ie junction of floor and wall or 2 walls
1/8 space= junction of 3 surfaces. ie corner.

you can model how a point source radiator behaves as It couples with one or more surface. Now coupling is frequency dependent(actually wavelength). and each boundary reinforces the signal.

This is also the reason that most speakers need baffle step compensation: at higher frequencies, the baffle acts as a plane and provides reinforcement. At lower frequencies, that reinforcement is not there and needs to be compensated. So you pretty much need to design a speaker system for where it will be placed. A fully compensated speaker System will sound boomy at the junction of one or more boundaries. And this is why some speakers need to be close to one or more boundaries to sound their best, it is because full BSC has not been applied. (It is typically applied in the crossover)

all of this is applicable to a theoretical point source radiator. In reality each speaker ( radiator) has some diameter or radiation surface, which impacts its behaviour predictably on a given baffle. That’s why we know that smaller diameter speakers drivers have better dispersion for higher frequencies, as they closer approximate a point source.

edit: sorry to hijack your thread. Happy to discuss this more offline over chat or a call

Thank you @kapvin

This is just a thread - the concept of "my" thread has disappeared for me - nothing is anybodys..

The learning for me is excellent - it stirs thoughts - i wondered why some speakers like the Linn Kan or the Naim SBL or Allaes play better when placed close to a wall when conventional thinking would call for the speaker to be placed far from the front wall - for imaging / soundstaging / other thread has a member asking for vertical height etc..

One adds 2 and 2 together and tries to understand what the "flat earth" audiophile as advocated in the past i must mention -by Linn and Naim must mean.

The learning is great and i thank you ( and all the contributors ) for that.

Please do keep contributing.

Was always a student and will be i guess.

best,

 

[sound_cycle]

i wondered why some speakers like the Linn Kan or the Naim SBL or Allaes play better when placed close to a wall when conventional thinking would call for the speaker to be placed far from the front wall - for imaging / soundstaging / other thread has a member asking for vertical height etc..

provisional answer - Dispersion pattern. Planars, horns, boxes will behave different.

Like with manuals which recommend dumping a sub into a corner and forgetting about it (because you can then energize all L/w/h modes and get the densest packing of stationary waves which *is* great for trouser flapping and rumbles) my answer above also ignores stuff like the room size, and listener position. And more importantly what is in the room and where that is - because a dimensionally symmetrical room is not necessarily acoustically symmetrical. (also factors which hugely influence reflected sound and the maya of image, or the distribution of nulls and peaks)

But if were to possible to hypothetically change dispersion pattern while keeping other things constant (not real world possible ofc) it would be the deciding factor.

We have to by necessity -let practical considerations, room constraints, WAF, budgets - decide what we are throwing out of the window and what we keep. Or live with. Or maybe ignore as ears adapt readily

I am very much - like you say above - keen on learning more about this (and my threads document hopefully some direction towards clarity, without any claim to following the only/ best route there)

ciao
gr

 

[mpw]

provisional answer - Dispersion pattern. Planars, horns, boxes will behave different.

Like with manuals which recommend dumping a sub into a corner and forgetting about it (because you can then energize all L/w/h modes and get the densest packing of stationary waves which *is* great for trouser flapping and rumbles) my answer above also ignores stuff like the room size, and listener position. And more importantly what is in the room and where that is - because a dimensionally symmetrical room is not necessarily acoustically symmetrical. (also factors which hugely influence reflected sound and the maya of image, or the distribution of nulls and peaks)

But if were to possible to hypothetically change dispersion pattern while keeping other things constant (not real world possible ofc) it would be the deciding factor.

We have to by necessity -let practical considerations, room constraints, WAF, budgets - decide what we are throwing out of the window and what we keep. Or live with. Or maybe ignore as ears adapt readily

I am very much - like you say above - keen on learning more about this (and my threads document hopefully some direction towards clarity, without any claim to following the only/ best route there)

ciao
gr

I suppose dispersion patterns and or the dispersion quantity will be affected by the presence or absence of BSC as indicated by @kapvin

see attached pic of an old Naim SL2 speaker

It always worked best only 6 inches from a wall

if you take it into the room it would not do as well

Maybe they took into consideration the living spaces of the customer and kind of marketed it that way - a close to the wall solution

Not many can have speakers 6ft from the front wall i suppose

 

[spirovious]

What l found that front ported speakers do sound better when placed near wall than rear ported most of the time. This may be most of FMs observation.May be it depending on how soundwave travels.

 

[kapvin]

I suppose dispersion patterns and or the dispersion quantity will be affected by the presence or absence of BSC as indicated by @kapvin

see attached pic of an old Naim SL2 speaker

It always worked best only 6 inches from a wall

if you take it into the room it would not do as well

Maybe they took into consideration the living spaces of the customer and kind of marketed it that way - a close to the wall solution

Not many can have speakers 6ft from the front wall i suppose

Hi @mpw, the speaker drive "sees" the baffle as a plane (or surface). so above a particular set of frequencies, it is functioning in "Half Space and gets a boost in volume (theoretically 6dB). for frequencies `where half the wavelength in more than baffle width(for a centrally mounter driver) the baffle no longer acts as a Plain (or surface), and the sound diffracts around the speaker and it radiates into full space, so there is no volume boost.

In the case of near wall placement the closer the speaker is to the wall, the more the low frequencies will see the wall as part of the baffle and get that boost. (Cinema speakers that are flush to the wall require no BSC for that reason) So absolutely, speakers can be (and are) designed to take that into consideration, and using them in a different way can result in stronger or less bass.

BSC can be applied through the crossover filter by reducing output above the BSC frequency or by adding drivers. The .5 in a 2.5way is an identical midbass, with only works to reinforce the output below BSC. and additional identical driver in a parallel circuit will add +6dB to the output for a given amplifier voltage so can full compensate for BSC.

the principle at work here is diffraction. this principle also dictates why tweeters need to be countersunk onto baffles (the tweeter faceplate needs to be flush with the baffle), with absolutely no gap between the tweeter faceplate and the baffle. even a 1mm gap can cause significant measurable response anomalies.

Dispersion, while not an inaccurate description in this case, is a more broadly used term, typically used to define the behaviour of the speaker at higher frequencies

 

[mpw]

Hi @mpw, the speaker drive "sees" the baffle as a plane (or surface). so above a particular set of frequencies, it is functioning in "Half Space and gets a boost in volume (theoretically 6dB). for frequencies `where half the wavelength in more than baffle width(for a centrally mounter driver) the baffle no longer acts as a Plain (or surface), and the sound diffracts around the speaker and it radiates into full space, so there is no volume boost.

half space= with the speaker on 1 reflective surface. typically the floor.

The wavelengths of sound frequencies audible to the human ear (20 Hz–20 kHz) are thus between approximately 17 m and 17 mm, respectively.

( is the above correct ?? )

so for a front baffle of 8 inches wide like my current Merlin TSM speaker, we will expect a 6 dB boost for all freq with wavelength above 100 mm ??

i guess this will start from 3000 Hz and above...

and BSC is a negative compensation / negative reinforcement right ??

above is simplistic but for me i am looking for broad answers ( unless notable exceptions ) so i can tighten my gut feel.

Kindly validate

thanks !

mpw