| acoustat question.... - Click HERE for Original Thread |
| newfinish |
| I bought 2+2 and wanted to know if I could put the panels horizontally instead of vertically.because my ceiling isnt high enough so I was thinking of stack 2x 2+2 8 panels per side horizontal .could that be good for image depth etc...or I would just loose everything....;) |
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| bear |
Yes.
That is called an Acoustat IV! :D
The bass is usually better that way...
A more rigid and stable frame is also a benefit, fwiw.
Change out the coupling caps, asap - use film caps, preferably polypropylenes. This will dramatically improve the imaging, moving the upper mids back into the same plane with the rest of the sound.
I also eliminated the fuse for the speaker line.
Other than that, enjoy.
_-_-bear
Oh... wait a second... turn them on their sides???:bigeyes: :rolleyes:
That's a different deal... you can, but the imaging will be a bit "funny".
Better to devise a new frame.
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| georgehifi |
| You could put all 4 pannels side by side, that would be a pair of Acoustat 4's, see pic. |
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| newfinish |
| yeah that's what I first thought but had an idea of placing them the other way around to have more panels could it be good for the sound other than having more sound? |
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| georgehifi |
If you place the pannels horizontaly and stack them 4 high you will have shocking horizontal dispersion, your hot seat will be 1 inch wide to be a scare monger.
Acoustat knew what they were doing, when they place 4 pannels side by side, stick to what they know.
Cheers George |
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| moray james |
| try building a set of vertical frames for just one panel. Situate the single panel about two and a quarter feet up off of the floor. The panels in a 2+2 are 9 inches wide. In this configuration you will get the best stage and image possible. You will need to make some connection changes inside the interface to optimise the interface for a single panel but these are just quick connects so it is fast and easy. You will need to run subs with this set up. However if it is stage and image that you are after then this is the way to go. Acoustat progressed from the side by side configeration to the vertical plus arrangement for this very reason. A pair of stereo subs should bring back all the impact that you will loose by giving up the extra panels. You may as well give this a try as you have nothing to loose and I can't see you switching back after you hear them this way. Just my 2 cents YMMV. Best regards Moray James. PS: if you wanted to run eight panels per side you would also need an extra set of interfaces to do it. Check out the model eight. Have a look at the ESL Circuit where there is tons of info on the Acoustat. |
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| newfinish |
thx guys:)
I will try first all 4 side by side :clown: |
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| bear |
| quote: | Originally posted by moray james
try building a set of vertical frames for just one panel. Situate the single panel about two and a quarter feet up off of the floor. The panels in a 2+2 are 9 inches wide. In this configuration you will get the best stage and image possible. You will need to make some connection changes inside the interface to optimise the interface for a single panel but these are just quick connects so it is fast and easy. You will need to run subs with this set up. However if it is stage and image that you are after then this is the way to go. Acoustat progressed from the side by side configeration to the vertical plus arrangement for this very reason. A pair of stereo subs should bring back all the impact that you will loose by giving up the extra panels. You may as well give this a try as you have nothing to loose and I can't see you switching back after you hear them this way. Just my 2 cents YMMV. Best regards Moray James. PS: if you wanted to run eight panels per side you would also need an extra set of interfaces to do it. Check out the model eight. Have a look at the ESL Circuit where there is tons of info on the Acoustat. |
Moray,
While in some respects a single panel will give a superior "image" , my experience (which includes 1+1s, and listing to single panels for testing) says that this is not the best way to go unless you like a "headclamp" listening position... the Acoustat panels are fairly beamy, actually quite beamy at HF, the purpose of the gentle curve to the multicell models (as you doubtless know) was to improve the overall horizontal dispersion.
One listen outside without any walls to reflect the sound would probably surprise most planar dipole owner! No reflections = very beamy sound!
The other problem with putting the single cell up about 2 feet or so is the issue of floor bounce - it will put a nice notch in the upper bass. Perhaps above the freq of a sub.
But, I prefer the "direct" bass sound of the Acoustat over the typical sub by a wide margin!
Proper set up in the room, and of the listening position will yield quite excellent "imaging" in general for the horizontal multicell Acoustats.
Fwiw, I prefer them toed in not flat out to the listening position, and the image perspective varies as you move +/- the "equilateral" point (speakers distance vs. listening distance), work with it.
I'd opt for running a III with the center cell full range and the outer two cells rolled off over a single cell, myself... :D
My personal experience with the entire line, save the model 8s, is that the 3 has better imaging than the 4, the 4 has the best bass of the 4 and down, the 2 isn't very good on the bottom, the 1+1 lacks bass and is a bit thinner in the midbass. The 6 is BIG. I prefer 3s overall as the best compromise - but I have kick *** subs if I need super low bass. 4s are quite impressive and kinda good if ur room is larger or you like louder for whaterver reason.
No matter what you absolutely need a 200wRMS class or larger amp unless ur room is rather small.
Change the coupling caps out for all polypropylene first chance you get.
Ymmv.
_-_-bear |
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| newfinish |
great!! the coupling caps are easy to find ?
I havent looked in the black boxes so far
I noticed they are medaillion with a red sticker
and that I have 5 wires running the panels instead of 3 like my freind has on his 2+2 ,do you know what difference it makes?
when you say horizontal you mean laying down or standing up fro the panels?
(Proper set up in the room, and of the listening position will yield quite excellent "imaging" in general for the horizontal multicell Acoustats. )
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| moray james |
your medallions have wires (stators) attached to both endes of the panels this does help a little in terms of driving the panels but it is not a big difference compared to the previous panel with stator connections just at one end only.
Bear: has been my experience that when you run Acoustats on realy good electronics (read stable into the load) the head in a vice effect is all but gone. Placing a single panel up off the floor is not an issue as the panels have very little dispersion in the direction of the length of the panel. I have found that lifting panels up off the floor and down from the ceiling by a foot or more actually helps to smooth out the line source output as there is gain from the floor and ceiling bounce and a little distance helps. Subs can be made to intigrate well but I won't argue with you over what these panels can do for bass but as you said you need big amps and space. I think that we can agree to disagree on those preferences. For those with limited space single panels with subs are great especially if you can place the outside edge of the panels right up against the side wall (in the acoustical null of the speaker) which really helps midbass output as well as floor space, not something you can do with a box speaker. Or if you have two front wall corners place the single panel as close into the corners (at 45 degrees) as the speaker base will permit. You get extra loading and zero worries of direct reflection of the backwave as it bounces put the sides and is delayed enough in the room from the front direct wave that the brin has no trouble recognizing it as a reflection so no smear. This position realy opens up floor space in small rooms and it works well. You can even give a listen to physically stacking panels one directly behind the other as this will give you additional output. Some very lite open cell foam (thin) between the panels will insure they don't buzz at all but you can tape them together just to experiment (maintain polarity of the panels). Have some fun. You might even consider biamping your Acoustats with a mono block driving each transformer. Never had the time to try this or known anyone else who ever tried but I am sure that it would yield a big improvement. Much easier job for the amplifiers in terms of load. Best regards Moray James. |
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| newfinish |
I bought my amps especially for the occasion of when I would get the acoustats.
I found a pair of mono blocks krell krs 100
they were made specifically for the apogee scintilla 1 ohm load,so acoustat will be a piece of cake:angel:
here is my room (had no time to decororate or paint)the speakers are my DIY'S,they play extremly well...but when acoustat are in town they are gone!! |
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| newfinish |
I bought my mono blocks especcially for the occaison that I would find either a pair of acoustat medallions 2+2 or a pair of apogee scintilla or divas on the market.
they are krell krs 100
double their power in class a down to 0.5 ohm(1600watts per channel)
they were made for the scintilla at the time for their 1 ohm load,but since they will be driving my acoustat if I right they are 4 ohm so wont be a problem:angel:
here is my setup(the place hasn't been decorated yet it's in the basement ,also the audio research sp9 is gone replaced by conrad johnson pv14L ,which has a much better image and depth but also better sound overall smooth and more character.for the price I think it's a piece tough to beat. |
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| newfinish |
| here is a close up.they weigh 185 pounds each.they are steal proof!! |
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| bear |
Dear newfinish,
May I offer you some suggestions, hopefully without appearing too critical or making you upset? I hope so.
After looking at the pic of your system, of which you are proud, my reaction was "oh dear"!
Here's why - the room! :bigeyes:
Hard floor, hard walls, hard ceiling, no absorption or diffusion!! :bawling: :yikes:
You definitely badly need to take some time to install something to do these tasks. It can be bought for purpose, homebrewed, or just "stuff" that normally goes into a room (bookshelves, wall hangings, etc...), it's necessary. Put a layer or two of padding under that rug too!!
The only other thought that I had is that while the Krell amps definitely are low Z champs, imho they are not champs in other regards. Imho, for the Acoustats, if you got something like a 150+ watt class tube amp with a pair of 811s with an all triode input & drive stages, you'd instantly relegate ur Krells to dust collection! :D
If and when you get those Apogee speakers, you may have to use the Krells then...:bigeyes:
_-_-bear :Pawprint:
PS. Yes, the coupling caps are easy enough to find. You have to be able to desolder/solder. You'll need either 50ufd or 200 ufd, depending on which set of caps are in your interfaces... just match the total capacitance of what is already there - you can ignore the value of the small caps. Then you need polypropylene caps (you can parallel them to get the total ufd amount) @ 200vdc rating or higher. Easy enough to find. Personally, I do not think you need to go for "exotic"/expensive "audio" caps. Regular or switching supply type polypropylene caps will do this job just fine. Surplus or stolen from dead computer monitor chassis (for example) works for me... ;)
You can remove the top "hatch" of the interface without removing the interface entirely, just make sure the speakers are unable to tip over - they are leaned up against something, etc... since the interface is part of the "stand" and you will be removing half of the mounting for that...
The caps are against the rear wall next to the HF control area... not the ones on the HV board in the center... :D |
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| bear |
| Here's how it looks if you go through the trouble of using cable ties, punching/drilling a few holes in a PCboard (or similar) and mounting them... the buss wire is #12 in this case. |
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| morricab |
I finished the mods on my 1+1s recently and getting that old electrolytic cap out of there worked wonders!! A whole other layer of grime was removed. I don't think there is much else you can do with these speakers except direct drive!
If you are going to stick with the interfaces then I recommend anything but Krell but primarily I recommend a powerful tube amp...especially an OTL. For some time I had a pair of Silvaweld OTL Tube Reference monoblocks on my Acoustats (100 watts with 4 6C33C tubes per monoblock) and it sang like no other amp in my experience. Just make sure you have good air conditioning!! It rasied the temp in my room by several degrees!
That being said I just got a minty pair of Acoustat Spectra 2200, which have a completely different transformer interface and sound dispersion concept. They are significantly more transparent than my moded 1+1s (same panels basically so it must be that interface). Looking at the schematic you can see that there are basically NO caps in the circuit path (just some small 0.01uF high voltage caps as DC blocking I think) unless you switch them to 100Hz mode (for integration of subwoofers). Transformers are completely different as well (one for + and one for - not one for bass and one for highs).
Seriously, don't put that Krell on them, you will regret it. |
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| newfinish |
| In 2 weeks the verdic will come as for the sound quality and db's.getting started on those straight panels,so about a foot from the floor for best bass and dispersion ,image etc? |
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| bear |
The idea, such as it is, is to approximate a large cylindrical surface with the 4 cells (in this case)... which works out to be something like a 5 degree angle (iirc) off parallel between each cell.
Then as far as height, the idea is to get the best compromise to make the center of the cells at ear height with the listener sitting down.
In fact the best bass would likely be with the cells forming a boundary with the floor. But that would put them a bit too low...
Acoustat actually set up the 2,3,4 models to tilt slightly back on the interface box (the rear feet are adjustable on the bottom), so that you would be at approx center sitting down, but with the tilt, you'd still have HF coverage standing up back in a larger room...
My feeling is that you will get the best results if you make a base & frame that is 100% rigid and solid, with at least one strut (no resonant, please) that holds the vertical ESL section solid to a point some distance back, beyond the normal distance of about 10" that the interface provided.
This is especially good IF you are also on carpeted floors, since the carpet tends to be rather like floating them in space...
When I made my "space frame" frames for three cells, the highs cleaned up considerably, which surprised me, since that wasn't my main obective at the time of design and construction. It was nominally to get them at ear height when standing on top of my Quadripole subwoofers...
_-_-bear
PS. I agree that the Krells are likely less than optimal in this application. |
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| newfinish |
thx for the input
so I should put them in an arc form like the sound labs?
not straight....ok does that help for image and stage?
and for the height then it's simple,pics in 2 weeks!!!
:smash: better get workin
the fram will be made in 1" mdf covered by another 3/4" bresilian teck wood. should be rigid:cool: |
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| newfinish |
| I decided to go in a straight line instead of an arc,seems to be better image but narrower sweet spot.but hey I'm the only one listening to it:angel: |
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| bear |
Rigid = way to hold the top motionless with respect to the base = triangle shape
Rigid = way to keep the base SOLIDLY on the floor.
We are talking about vibrations at audio freqs, not gross rocking motions visible to the naked eye... (think about a tuning fork for example, very solid on the bottom where it is held...)
;)
_-_-bear :Pawprint: |
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| newfinish |
guys have you ever heard a pair of KRS krells???
they have the best bottom body an amp could hope for,sonically,a guy I know who's friend told him that as soon I'm finished with them acoustat want to here it again because the first time he stood in front of a paire of 2+2 and the KRS he was blown away,on how the dynamics were powerful and the rest of the qualities of the acoustats were brought to life,these are reference amps of krell in 1990,they DO NOT COMPARE TO ANY MODELS OF KRELL.(I needed to empasis on that):) |
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| newfinish |
| almost done will have pics of the wood panels tommorrow before paint;) |
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| newfinish |
[IMG] [/IMG]
All what's missing is a few days of recharging....
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| Capaciti |
Hi newfish,
absolutely crazy!! Nice work.
Are the crossbars at the rear on the original acoustats as well ? I would expect heavy reflections to the membrane. Unfortunately the crossbars are exactly in the height of the listening center.
i made a lot of testing and any "concrete" material near to the membran causes issues on spectral decay.
Capaciti |
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| newfinish |
| quote: | Originally posted by Capaciti
Hi newfish,
absolutely crazy!! Nice work.
Are the crossbars at the rear on the original acoustats as well ? I would expect heavy reflections to the membrane. Unfortunately the crossbars are exactly in the height of the listening center.
i made a lot of testing and any "concrete" material near to the membran causes issues on spectral decay.
Capaciti |
these are brand new 1"mdf made by cnc cutting(one peice)and another 1 1/4" added on top to addd stiffness and to be flush with the panels.I have 1/8"pure wool between the panels and the frame,haven't found any differences so far...can you be more detailed when you spectral decay... what do you mean it
resonates?
I did another paire to a guy that he didn't put back his felts and he didn't feel any differences than before other than having the panels straight is an awsome improuvement stage,image,width,depth etc...
:xeye: |
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| Capaciti |
Hi newfish,
i didnt meant the horizontal bars, but the vertical one in the middle of the height.
I constructed an ESL with about the same area of one acoustat element and added a support structure at the rear. It consisted of two small horizontal supports and 6 vertical supports, all about 4 inches distant to the ESL element. When i measured spectral decay, there was a significant delay in the mid range. In addition the sound appeared coloured and i had the feeling always to locate the speaker. So i cut off the whole support structure,having nothing behind the panel anymore and the delay has gone. Transparency appeared again .
Even if you damp the crossbar it will reflect back to the membrane, since any material wont absorb the waves completely.
In order to evaluate you can mount several more vertical crossbars, made form wood with the same width of the excisting one. Just fix them short term and listen. You should be able to hear the increasing negative effect due to the crossbars.
Capaciti |
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| Capaciti |
Hi,
sorry, i was wrong and mixed horizontal and vertical. I mean the vertical one in the middle of the height to be critical
Capaciti |
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| newfinish |
the verticals i need them cause that 's where i screw them up.
so they don't interfer with the panels |
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| Few |
| quote: | | Capaciti wrote: "sorry, i was wrong and mixed horizontal and vertical. I mean the vertical one in the middle of the height to be critical" |
I think Capaciti may mean the horizontal bar along the back--the one that ends up parallel to the floor and at about ear level.
As for the felt test, I don't think 1/8" of wool felt would be sufficient to kill the reflections Capaciti is referring to so comparing the sound with and without felt may not reveal any reflection problems. Since I doubt you want to hack up your nice new frames just to do a test, perhaps you could take an individual isolated panel and listen (or better yet measure) with and without a piece of mdf located where your crossbrace would be. Capaciti's suggestion that you add extra crossbraces, just to determine if they cause audible problems, is another good approach and it might require less work.
In any case, nice job so far.
Few |
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| newfinish |
well my freind that I did the same frame placed the new frame in front of his original frames that he cut in 2 and placed them side by side still connected,and didn't notice any change what so ever in the sound.let me tell you he can spend 12 hrs straight just to test any changes in his sound system,:xeye: he's a sound freak:clown: that why we went with that type of frame alot less vibration then the original.
and I modified a couple of suggested tweaks ans the mids highs are very neutral than the first time and are more spread out through the panel,which in that case has less of difference if your standing up or sitting,much more detail,image is wider,deeper,bass also was augmented,the timbres were more natural,you can hear all the sound of a close microphone singer can do with his mouth.as if the singer was right there!!
rebecca pidgeon with spanish harlem is phenomenal!!!
norah jones with her velvety voice just gives you gose bumps!!:angel: I can say also that the dynamics were much better.
what I changed was the 47uf cap with new connector and wire 12gauge.
canceled the fuse also.
and cardas pure copper connectors the one with the black rectangle.the best connection you can get,close to 93%
thx for all your info's everyone!!!BEAR you rock:cool:
ooh yeah and the back wall I tried a 40"x80"eggshell foam with a sonopan to hold it around mid high in the middle of the back wall.behind me when I sit and listen and wow the sound much richer.....it's getting there!!!and behind the speakers is still just the quilted blanket of coton which does the right job,cause I tried to dampen the side walls behind and it got worst so stayed with the quilt and so far my best moves. |
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| bear |
Rock on!
Now, loose the Krills, and build/buy urself a ~150-200w class triode tube amp for them. The Krills will sound thin and anemic and hard and mechanical by comparision, I promise.
Think of all the $$ you can get for them! :D
You want to go AB2, and you can use 211/845s biased properly, or 811a or a whole range of other tubes... just so long as you set them up as triodes you might even get away with p-p paralleled things like 6550s... (not my fave).
_-_-bear |
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| newfinish |
I'll get to you on that for the amps later ...:cool:
I was wondering if 3 days minimum of charging the panels is normal?
cause the sound is awfull if I don't wait at least 3 days for them to charge can someone tell me ?
and could it be possible ,after further listening that the cap that I changed needs somme break in?
and I read that a guy modified the top of the wires on the panels and got them all soldered together and got the 5000volt to 7000volt modification,but he didn't tell why and what it did actually as a modification.any input on that could be apreciated.
thx:D
oh and the bass seems to travel on the ceiling rather then the floor or mid height,not that i don't have any but when you stand up you have more what could I do to help that?
fell on this site and haven't read yet the possibilities but gonna get on it this week...:att'n:
http://www.rivesaudio.com/ |
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| bear |
Three days seems a bit much... but 24hrs isn't unusual.
Is it exceptionally dry there?
Maybe wet??
Sounds like the HF is on axis in the seated position and off axis when you stand up - therefore the HF rolloff = bass boost in perceptive terms?
Don't think I want to go to 7kv on the panels... tzap! zorch!
Of course you could have room boost modes in the standing position too... move the speakers!
What is the ceiling?
And, there is the effect of floor bounce, especially if you have a live floor!
Can you measure the difference? <---idea!
_-_-bear |
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| newfinish |
the humidity is 40% (I have a hygrometer I do floors for a living)
all the guys that come in the room say that the reflections sound funny cause it's as if you didn't have all the frequencies reflecting the hf are reflecting much more the mid low,.
the ceiling is made of 2'x2' suspended tentest 5/8" inch thick.in between I have air,naturally,and roxulsound 3" inch thick of that ichy stuff:apathic: the walls are all gypse with concrete behind,expte for one wall,which has 2 ciment post about 8"x8"
the size is 37'long 13'wide 7'tall.
tommorrow I will experiment them firing downward of about 3 degres ust to see if the bass tends to go vibrate on the floor more. |
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| Capaciti |
Hi Newfish,
are there furnitures in your listening room ? If not,your romm should show echoes. From the pictures your room appears to be "naked" and should sound like a tunnel. If yes thats critical
Just try it, by clapping your hands. If you hear an echo, absorbtion is required. The bass issue might be a result of an echo between the rear walls of the speaker and the wall behind listening position.
3 days is very long for loading. It looks like the coating has aged and cannot be fully charged by one high voltage supply. To ensure full loading you can add an second source, while each source feeds two panels instead one feeding four panels.
Regarding Amps: Although Class-D amps are not the favourite of most people, you should try them with an ESL, since they do not care about the capacitive load of an ESL and do not waste more than 70 % electrical power as normal amps do. I got a lot of feedback from people, who suddenly loved their Quads when running with Class-D (e.g. Tact or the german DIY-amps from HiFiakademie)
Regards, Capaciti |
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| newfinish |
finally I got really good results with adding bass trapps and by changing the the caps in the signal path and by changing the wire connector,ans speaker connectors also for cardas top of the line better then wbt.
I also changed my preamp which gives more of everything.bass dynamics,mids,highs and more natural feel to the timbres.
[IMG] [/IMG] :angel:
MY REAL PICS A RE COMMIN... |
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| newfinish |
here are a few mods I made:
revelation 1 meter interconnect for dac and preamp.
premier 10 mint mint mint.did I say mint?
new amperex tubes for the dac 300$ a pair!! 200$ on special.:clown:
but hey it's very well worth it.
the next move will be having the whole kit move closer to me and the amps stay there.
and the amp rack did it myself
2" thick birch
I don't like paying 3000$ for a piece of furniture that big.
total cost of rack 35$
[IMG] [/IMG] |
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