ucla88 said:
Did Rick describe his room yet? I don't remember there being a description other than for the walls. Around here, new and more upscale homes are being built with large living rooms, high ceilings, lots of windows, and wood floors. This can definitely create problems for dialogue as well as just trying to have a conversation with someone sitting across the room. Just having carpet helps a whole lot as it absorbs the mid/high frequencies which are generally the problem.
Again, around here, movie theaters have carpet and covered walls and generally have a lot less high frequency reflections that a typical home. The problems most theaters have is pushing the sound system too hard, not maintaining the sound system, or not maintaining the projecter (since, with the exception of DTS, the sound for movies is on the film).
Anyway, in Rick's case, if he has wood floors in the room than I can totally understand his problem as I would have the same problem (and do at friend's homes that have wood floors). If this is the case that I would try putting down a blanket on the floor between where one would usually sit and the speakers. If that fixes your problem I would go and look for a rug you can put down in the same spot, which should help. If you have lots of windows, I'd try putting blankets over them. If that fixes your problem I'd look at getting drapes that you can cover them up with when watching television. Having padded cloth-covered couches also will help some as they act as broadband absorbers (leather/vinyl reflects some highs, I believe). If your problems are caused by the hard walls, try (again) putting a blanket over it to see if it help. The wall closest to or behind you or the one behind your speakers are the ones most likely to cause problems, I believe. If that fixes your problem, you can maybe look into tapestries to put over the offending wall
I'd just make sure you rule out your acoustics before getting new speakers. New speakers may help, but some mid/high absorbtion will probably help more.
Hope this helps.
Ben.
Ben said
> Did Rick describe his room yet?
Damn relevant point. 4.3 * 3.7 m * 3.3 m high (14* 12 *11 ft) mostly open on one side. One small window. Timber floor but a huge covers most of, lots of lounges. Liveliness as determined by clapping, is not marked.
> new . . homes are built with . . . lots of windows
The worst thing fort acoustics. We have a room like that, into which the SL Phoenix will shortly be going.
A friend just moved into a new architect designed townhouse with concrete floor & a wall of glass about 5m * 6!m high (16 * 20 ft). If there’s more then two noies sources (people/ tv/ audio) in there it’s horrific!
> if he has wood floors. . .
Another room with bare wood floors ~ not audiophile but to me sounds great for music – a nice reverb
You’ve good suggestions for acoustic derived fidelity problems.
But this problem: your suggestions have clarified that it’s not the room.
I'm keen to get a new speaker, in fact the Jordan 92 is calling me like a siren. If it doesn't help I can find a good home for it.
I should play around with mid/high absorption too.
Rob
> frequency vs reflectiveness of the room?
I need to get back my Master Handbook of Acoustics & let you know.
Cheers
> Did Rick describe his room yet?
Damn relevant point. 4.3 * 3.7 m * 3.3 m high (14* 12 *11 ft) mostly open on one side. One small window. Timber floor but a huge covers most of, lots of lounges. Liveliness as determined by clapping, is not marked.
> new . . homes are built with . . . lots of windows
The worst thing fort acoustics. We have a room like that, into which the SL Phoenix will shortly be going.
A friend just moved into a new architect designed townhouse with concrete floor & a wall of glass about 5m * 6!m high (16 * 20 ft). If there’s more then two noies sources (people/ tv/ audio) in there it’s horrific!
> if he has wood floors. . .
Another room with bare wood floors ~ not audiophile but to me sounds great for music – a nice reverb
You’ve good suggestions for acoustic derived fidelity problems.
But this problem: your suggestions have clarified that it’s not the room.
I'm keen to get a new speaker, in fact the Jordan 92 is calling me like a siren. If it doesn't help I can find a good home for it.
I should play around with mid/high absorption too.
Rob
> frequency vs reflectiveness of the room?
I need to get back my Master Handbook of Acoustics & let you know.
Cheers
Room reverb
Rick. we have a room 10 metres by 6m by 3m(av) high, polished wood floor, the odd rug, walls two thirds glass, ply ceiling and typical living room furniture. Both my wife and I suffer from loss of highs, (or rather sharp transients), making it more difficult to distinguish between sounds like T's,and D's. Conversation for us in this room can be a strain, if noise levels are high, or people speak softly, although our children can cope OK. Even they find TV speech poor in this room. Adding volume does not help, there is a critical volume at which intelligability is best.
So it is not just a matter of speaker design. (Nor, before you comment, are hearing aids the total cure)
If this is your situation, headphones are the only simple and universal answer for recorded voice. (Other than modifying the room severely- and I mean severely, a few rugs won't help)
On both radio and TV, some programs are impossible, others OK, depending on the recording and any background noise it may have.
If earphones are not acceptable, the speaker/electronics choice can improve, (but not totally cure), matters.
I have tried different speaker types, and certainly the small metal cones are better, and frequency shaping will also help. Any degree of bass or mid-bass heaviness will cause major problems, as will any distortion, such as may occur when demanding too much from small cheap paper cone speakers.
Rather than HF reflections being the problem, it seems control of the lower frequencies provides the best results, associated with mid-range clarity. The latter means soft cones, (poly and similar) that tend to round the corner of transients, should be avoided.
In the above room, on music, the adverse effects are not nearly so severe, and good results can be had with some care.
My large transmission lines, (excellent in our previous house with a totally different room structure), in this new room blur music badly as well, and have been discarded. The main room engentones seem to co-incide with some of their peaks.
Also, the amplifier type has a noticable effect, as some do not control the TL's as well as others.
Smaller speakers definitely cope better, and amplifier effect is less.
I suspect class D amplification may also improve matters. An early Class D I used years ago seemed to exercise better cone control than either of my two amps of the time, one valve, the other SS, (but had other problems causing me to discard it, specifically high noise, and RF radiation). I plan to try a modern one.
Avoid any floor/corner coupling, and taylor the bass speaker response for best results to avoid triggering room resonances. This may require broad notch filters.
Currently I am building a 3 way active with metal cones which I hope will acheive good results on music. I will probably include a specific taylored mid-range response for speech.
Interestingly enough, it is still easy for me to distinguish the quality of reproduction of music by differing equipments in this room, suggesting that perceived frequency response may not be a major factor with modern equipment.
Rick. we have a room 10 metres by 6m by 3m(av) high, polished wood floor, the odd rug, walls two thirds glass, ply ceiling and typical living room furniture. Both my wife and I suffer from loss of highs, (or rather sharp transients), making it more difficult to distinguish between sounds like T's,and D's. Conversation for us in this room can be a strain, if noise levels are high, or people speak softly, although our children can cope OK. Even they find TV speech poor in this room. Adding volume does not help, there is a critical volume at which intelligability is best.
So it is not just a matter of speaker design. (Nor, before you comment, are hearing aids the total cure)
If this is your situation, headphones are the only simple and universal answer for recorded voice. (Other than modifying the room severely- and I mean severely, a few rugs won't help)
On both radio and TV, some programs are impossible, others OK, depending on the recording and any background noise it may have.
If earphones are not acceptable, the speaker/electronics choice can improve, (but not totally cure), matters.
I have tried different speaker types, and certainly the small metal cones are better, and frequency shaping will also help. Any degree of bass or mid-bass heaviness will cause major problems, as will any distortion, such as may occur when demanding too much from small cheap paper cone speakers.
Rather than HF reflections being the problem, it seems control of the lower frequencies provides the best results, associated with mid-range clarity. The latter means soft cones, (poly and similar) that tend to round the corner of transients, should be avoided.
In the above room, on music, the adverse effects are not nearly so severe, and good results can be had with some care.
My large transmission lines, (excellent in our previous house with a totally different room structure), in this new room blur music badly as well, and have been discarded. The main room engentones seem to co-incide with some of their peaks.
Also, the amplifier type has a noticable effect, as some do not control the TL's as well as others.
Smaller speakers definitely cope better, and amplifier effect is less.
I suspect class D amplification may also improve matters. An early Class D I used years ago seemed to exercise better cone control than either of my two amps of the time, one valve, the other SS, (but had other problems causing me to discard it, specifically high noise, and RF radiation). I plan to try a modern one.
Avoid any floor/corner coupling, and taylor the bass speaker response for best results to avoid triggering room resonances. This may require broad notch filters.
Currently I am building a 3 way active with metal cones which I hope will acheive good results on music. I will probably include a specific taylored mid-range response for speech.
Interestingly enough, it is still easy for me to distinguish the quality of reproduction of music by differing equipments in this room, suggesting that perceived frequency response may not be a major factor with modern equipment.
Rjb
We are not alone!
> Both my wife and I suffer from loss of highs (or rather sharp transients) making it more difficult to distinguish between sounds like T's,and D's.
I believe that the most critical Hz for discerning consonants is c. 2000 Hz. Is that your understanding?
> Even they find TV speech poor in this room.
Another acoustically inept designer??
> headphones are the only simple and universal answer for recorded voice.
I should see how I go with the old Stax, although the cord may not be long enough.
> certainly the small metal cones are better . . . soft cones (poly and similar) that tend to round the corner of transients, should be avoided
After initially leaning to the new CSS WR125S paper cones, I opted for the metal cone Jordan 92s.
> and frequency shaping will also help.
What do you find best to boost and lower??
> bass or mid-bass heaviness will cause major problems
I don’t mind it in music; but speech is virtually the opposite.
> it seems control of the lower frequencies provides the best results
Other than in the crossover, is there anything you do to the room?
> Smaller speakers definitely cope better
Relatively less bass/ smaller drivers with more detail?
> I suspect class D amplification may also improve matters.
An amp guru recently experimented with the current crop of class D, and thought – great for bass, but not so good for voice.
> Avoid any floor/corner coupling,
I probably should know how to do that, but don’t.
> I am building a 3 way active with metal cones which I hope will acheive good results on music. I will probably include a specific taylored mid-range response for speech.
My speker plan:
On the L&R 4.5” metal cones built on a Seas alnico magnet (that I got for a good bottle of red!), probably with the small Aurum Cantus ribbons & probably an Usher 7” bass.
and in the centre 4.5” Jordan 92s. They’re full range so I probably won’t use a tweeter, though some use an Aurum ribbon. I have some unemployed Peerless XLS so while they’re’ big, they’re low distortion and work well in a small box.
I may go semi active with gainclones. Low cost GCs can get congested, but I don’t know about the premium component ones . .
What are your 3 way ideas??
> it is still easy for me to distinguish the quality of reproduction of music by differing equipments in this room, suggesting that perceived frequency response may not be a major factor with modern equipment.
. . Not sure what you mean by the suggested conclusion?
Cheers
We are not alone!
> Both my wife and I suffer from loss of highs (or rather sharp transients) making it more difficult to distinguish between sounds like T's,and D's.
I believe that the most critical Hz for discerning consonants is c. 2000 Hz. Is that your understanding?
> Even they find TV speech poor in this room.
Another acoustically inept designer??
> headphones are the only simple and universal answer for recorded voice.
I should see how I go with the old Stax, although the cord may not be long enough.
> certainly the small metal cones are better . . . soft cones (poly and similar) that tend to round the corner of transients, should be avoided
After initially leaning to the new CSS WR125S paper cones, I opted for the metal cone Jordan 92s.
> and frequency shaping will also help.
What do you find best to boost and lower??
> bass or mid-bass heaviness will cause major problems
I don’t mind it in music; but speech is virtually the opposite.
> it seems control of the lower frequencies provides the best results
Other than in the crossover, is there anything you do to the room?
> Smaller speakers definitely cope better
Relatively less bass/ smaller drivers with more detail?
> I suspect class D amplification may also improve matters.
An amp guru recently experimented with the current crop of class D, and thought – great for bass, but not so good for voice.
> Avoid any floor/corner coupling,
I probably should know how to do that, but don’t.
> I am building a 3 way active with metal cones which I hope will acheive good results on music. I will probably include a specific taylored mid-range response for speech.
My speker plan:
On the L&R 4.5” metal cones built on a Seas alnico magnet (that I got for a good bottle of red!), probably with the small Aurum Cantus ribbons & probably an Usher 7” bass.
and in the centre 4.5” Jordan 92s. They’re full range so I probably won’t use a tweeter, though some use an Aurum ribbon. I have some unemployed Peerless XLS so while they’re’ big, they’re low distortion and work well in a small box.
I may go semi active with gainclones. Low cost GCs can get congested, but I don’t know about the premium component ones . .
What are your 3 way ideas??
> it is still easy for me to distinguish the quality of reproduction of music by differing equipments in this room, suggesting that perceived frequency response may not be a major factor with modern equipment.
. . Not sure what you mean by the suggested conclusion?
Cheers
RobWells said:
I think I was wrong there
. Of interest in the book (just a quick skim I'm afraid) is that speech clarity requires lower reverberation times than music. In a small recording studio it suggests reverberation times for speech as approx 1/2 that of music. 1000 - 3000 cu ft speech is suggested at ~ 0.3 seconds against 0.5 ish for music. A bit busy tonight, so cannot help much more.Also you said this :
A horn would help the person it’s pointed at (our room is very spread out) but not all people, but I’m the one with the problem & doing the work, so that’s ok.
How does the off axis drop of a full range compare with a horn ?
Cheers,
Rob
azrix said:
Well, I happen to live in one of those houses you describe. A rather large family room, ~33x25 with high ceilings, open to other rooms with vaulted ceilings, lots of glass.
Nonetheless, the RT60 in my room is pretty average. I can't recall the exact number offhand, but it was fairly typical.
The reality is reverb is not usually a problem. The rooms just aren't that big. It doesn't matter how reflective the walls, celing and floor is, the echos just won't be delayed enough.
Now floor bounce and room modes may be a problem, but just a little bit, since these will start to be less of an issue over 400 hz.
The best thing to do is to measure RT60. If it's average for a small to medium room, then the room is fine as far as voice intelligibility goes. If the room is a bit live, sure, some overstuffed chairs, pillows, throw rugs etc.
ucla88 said:
Well, it's the wood flooring that's the issue here. Every room like yours that I've been in that has wood floors has problems with speech intelligibility above or below a narrow volume level, from a person or a stereo or TV. Normal carpet, in particular the padding under the carpet, does a lot to help with this problem. It's when you have every surface in your room that's reflecting sound that there's a problem. Your reverb time in the midrange goes way up and you begin to have masking effects. Sound diffusion can help some, but that usually has about the same size/space requirements as absorbtion. Also, with wood flooring, any extra noise inside the room can also play havoc on intelligibility, such as someone just walking through the room (sound from foot falls and the wood creaking underneath) or central heat/air. Rugs will not help with all of this as much as just carpeting the room but they can help. Not to say that carpeting is a fix-all, just that I think, for most homes, it fixes the most problems with the least effort/invasiveness.
Rigid fiberglass absorbers are the most efficient here. Owens Corning 703 and 705 (or equivalent) covered in fabric works wonders. The 703 will also work great as a mid/high absorber. http://www.ethanwiner.com/acoustics.html is a great article about all of this, though it's more focused on studio and not home acoustics. That site also has plans for absorbers using rigid fiberglass.
Well, it could still be the room. My suggestions were just the easiest and most aesthetically pleasing ones I could think of. Based on what you had written previously, the room sounded like the most likely culprit for your problem. If you could talk your SO into cloth covered panels, which can be made to match your decor, you can have much better acoustics by building some fiberglass absorbers that I mentioned above and placing them in the right spots. If your new speaker doesn't fix your problem, then you might give them a shot.
Originally posted by rick57 I'm keen to get a new speaker, in fact the Jordan 92 is calling me like a siren. If it doesn't help I can find a good home for it.
Well, far be it from me to keep anyone away from new toys.
Ben.
azrix said:
My room must be a counter example -- douglas fir -- no carpets (due to dust mite allergies). The room is a bit bright but mo intelligibility problems -- and further ther is a parade of speakers thru here (Dynaco A50s at the moment, but back to the $7 open baffles as soon as i can get the next round of tweaks done.
dave
Room effects
Rick- The room treatment suggested in various posts above, such as full and heavy pile carpeting with thick underlay, absorbent panels on walls and ceiling etc certainly work in some situations- as will breaking up the room by freestanding walls. This is what I meant by extreme modification.
The other point I did not make clear was that our room is effectively sealed. Any significant opening will change results noticably. It is not just a matter of reflective surfaces bouncing the sound around, (although this can be noticeable in some situations too). We can open a full third of one long wall, and the intelligability improves considerably. This still leaves the floor-ceiling effect though, (with a significant boost around 150 hz) and is not a full cure.
Size of room also changes things. my wife has just been in a smaller but similarly constructed room, about two thirds the volume, and intelligability was worse. Rooms much smaller do seem better however, probably because the furnishings typically form a larger percentage of absorbent surfaces and volume.
Treating a room for best sound requires individual tayloring, and trial and error. Various textbooks can only give a general guide. Other living priorities made this approach unaccepatable for us. However, despite my earlier comment that scattering a few rugs around is virtually useless, we will be doing a little of that.
Re headphones, the cordless type are convenient, (we use cheap RF FM), but the quality is not adequate for serious listening to music. But as discussed music seems to survive much better than speech.
Re speakers, I have done considerable experimentation, with various size/type of cones, even hauling out some old Jordan Watts. As a result I am doing much as you propose, ribbon tweeter, dual Seas L12s, both mounted at ear level in very thin towers. Seperate twin Al sealed subs, probably Dayton 7 inchers. Active, with adjustable filters on both mid and bass. I expect to have to experiment a lot for best results, In particular the subs may have to be fixed in location, and the electronics adjusted to suit. (If they move, the compensation would then be all wrong.). The towers are more flexible in location.
All the electronics will be internal to the speakers.
I have some reservations re chip amps, although my Linn Klassic seems OK with the current speakers on it. I tend to agree with some of the ideas expressed by Graham Mainyard that amplifier measurement is not the full story, and "first-cycle" and speaker loading effects can be significant. I would like to use all LJH type amps, but heat would certainly be a major problem, and power insufficient for the bass I suspect. Hence my interest in trying class D, but those I have heard so far in commercial gear have not been up to the standard of best convenional amps.
As a result of work by Zaph and others (including MarkMk), I was temped to try 4 Aura 3"s or BS3's in an even thinner tower, but could not get as good a simulation with the particular external appearance I was aiming for.
Rick- The room treatment suggested in various posts above, such as full and heavy pile carpeting with thick underlay, absorbent panels on walls and ceiling etc certainly work in some situations- as will breaking up the room by freestanding walls. This is what I meant by extreme modification.
The other point I did not make clear was that our room is effectively sealed. Any significant opening will change results noticably. It is not just a matter of reflective surfaces bouncing the sound around, (although this can be noticeable in some situations too). We can open a full third of one long wall, and the intelligability improves considerably. This still leaves the floor-ceiling effect though, (with a significant boost around 150 hz) and is not a full cure.
Size of room also changes things. my wife has just been in a smaller but similarly constructed room, about two thirds the volume, and intelligability was worse. Rooms much smaller do seem better however, probably because the furnishings typically form a larger percentage of absorbent surfaces and volume.
Treating a room for best sound requires individual tayloring, and trial and error. Various textbooks can only give a general guide. Other living priorities made this approach unaccepatable for us. However, despite my earlier comment that scattering a few rugs around is virtually useless, we will be doing a little of that.
Re headphones, the cordless type are convenient, (we use cheap RF FM), but the quality is not adequate for serious listening to music. But as discussed music seems to survive much better than speech.
Re speakers, I have done considerable experimentation, with various size/type of cones, even hauling out some old Jordan Watts. As a result I am doing much as you propose, ribbon tweeter, dual Seas L12s, both mounted at ear level in very thin towers. Seperate twin Al sealed subs, probably Dayton 7 inchers. Active, with adjustable filters on both mid and bass. I expect to have to experiment a lot for best results, In particular the subs may have to be fixed in location, and the electronics adjusted to suit. (If they move, the compensation would then be all wrong.). The towers are more flexible in location.
All the electronics will be internal to the speakers.
I have some reservations re chip amps, although my Linn Klassic seems OK with the current speakers on it. I tend to agree with some of the ideas expressed by Graham Mainyard that amplifier measurement is not the full story, and "first-cycle" and speaker loading effects can be significant. I would like to use all LJH type amps, but heat would certainly be a major problem, and power insufficient for the bass I suspect. Hence my interest in trying class D, but those I have heard so far in commercial gear have not been up to the standard of best convenional amps.
As a result of work by Zaph and others (including MarkMk), I was temped to try 4 Aura 3"s or BS3's in an even thinner tower, but could not get as good a simulation with the particular external appearance I was aiming for.
Rob
> speech clarity requires lower reverberation times than music
Ah, haah I see.
> How does the off axis drop of a full range compare with a horn ?
I thought a horn gave more concentrated ie more sound within its flare range eg 90* 40, but less outside that. Is that incorrect?
DSP_Geek
> Hearing loss tends to occur on a band centered around 4 kHz, not surprising since the ear is most sensitive there, and that's where most transient energy lives.
Hearing loss Hz is different to the most critical Hz for discerning consonants ie voice intelligibility.
ucla88
> measure RT60.
I believe I’d need to buy & use eg ETF US $ 150.
> If it's average . . then the room is fine as far as voice intelligibility goes
Then the only avenues are better speakers/ headphones/ better amp/ HT processor.
Ben
> Owens Corning 703 and 705 (or equivalent) covered in fabric works wonders.
In the table at http://www.ethanwiner.com/acoustics.html, “Typical Acoustic foam” performs similar to the 703 from 1000 – 4000 Hz! I’d have to check that the right spots acoustically are also acceptable to the resident décor expert.
Dave
> My room must be a counter example
to every “rule” there is an exception . . or maybe you have golden ears
rjb
> Any significant opening will change results noticably. . . We can open a full third of one long wall, and the intelligability improves considerably. This still leaves the floor-ceiling effect though.
My room is 75% open on side, which further emphasises that the room is probably not the main culprit.
You weren’t suggesting that cordless headphones are adequate for speech?
> Re speakers . . adjustable filters on both mid and bass.
Great idea!
> I expect to have to experiment a lot for best results
. . the way of the world
> amplifier measurement is not the full story, and "first-cycle" and speaker loading effects can be significant.
Agree.
> work by Zaph and others (including MarkMk) . . 4 Aura 3"s or BS3's
I’ll have to check it out www.diyaudio.com/forums/showthread.php?s=&threadid=49711&perpage=10&pagenumber=1
Cheers!
> speech clarity requires lower reverberation times than music
Ah, haah I see.
> How does the off axis drop of a full range compare with a horn ?
I thought a horn gave more concentrated ie more sound within its flare range eg 90* 40, but less outside that. Is that incorrect?
DSP_Geek
> Hearing loss tends to occur on a band centered around 4 kHz, not surprising since the ear is most sensitive there, and that's where most transient energy lives.
Hearing loss Hz is different to the most critical Hz for discerning consonants ie voice intelligibility.
ucla88
> measure RT60.
I believe I’d need to buy & use eg ETF US $ 150.
> If it's average . . then the room is fine as far as voice intelligibility goes
Then the only avenues are better speakers/ headphones/ better amp/ HT processor.
Ben
> Owens Corning 703 and 705 (or equivalent) covered in fabric works wonders.
In the table at http://www.ethanwiner.com/acoustics.html, “Typical Acoustic foam” performs similar to the 703 from 1000 – 4000 Hz! I’d have to check that the right spots acoustically are also acceptable to the resident décor expert.
Dave
> My room must be a counter example
to every “rule” there is an exception . . or maybe you have golden ears
rjb
> Any significant opening will change results noticably. . . We can open a full third of one long wall, and the intelligability improves considerably. This still leaves the floor-ceiling effect though.
My room is 75% open on side, which further emphasises that the room is probably not the main culprit.
You weren’t suggesting that cordless headphones are adequate for speech?
> Re speakers . . adjustable filters on both mid and bass.
Great idea!
> I expect to have to experiment a lot for best results
. . the way of the world
> amplifier measurement is not the full story, and "first-cycle" and speaker loading effects can be significant.
Agree.
> work by Zaph and others (including MarkMk) . . 4 Aura 3"s or BS3's
I’ll have to check it out www.diyaudio.com/forums/showthread.php?s=&threadid=49711&perpage=10&pagenumber=1
Cheers!
Rick,
Chapter 3 of the sound system design manual here:
http://www.jblpro.com/pages/tech_lib.htm
Will give you more info than I ever can.
Also theres a couple of papers on speech intelligibility there aswell ( haven't read them yet)
Cheers,
Rob
Chapter 3 of the sound system design manual here:
http://www.jblpro.com/pages/tech_lib.htm
Will give you more info than I ever can.
Also theres a couple of papers on speech intelligibility there aswell ( haven't read them yet)
Cheers,
Rob
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.