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rs237
02-27-2008, 12:34 PM
hello,
before I start my new Projeckt , I have a question. Does it make sense in an room of 4m X 4m (13ft X13ft) large monitor Speaker (JBL4355, JBL4435, EverestII:D) to operate ? It would be beneficial to Speaker in the wall to install? If so what would be the best amount?
Every opinion is welcome.

thanks

juergen

Ian Mackenzie
02-27-2008, 12:40 PM
No it does not make sense but we do it any way.

What out for room mode if it is a square room.

Andyoz
02-27-2008, 01:12 PM
I'd do it but definitely "soffit" mount them.

You're gonna need some low-freq absorption in that room so make sure you are not putting them in the typical masonry/concrete bunker so common in the EU.

Hoerninger
02-27-2008, 01:40 PM
And watch for early reflections, some dampening at the walls will be necessary to avoid them. The room is not a big one.
My next listening room, mainly an office, will only be slightly bigger 14ftx14ft, so I will look at your results.:D
____________
Peter

PS: Possibly interesting by INFINITY:
Floyd E.Toole: Loudspeakers and Rooms - Working Together
http://www.harmanaudio.com/all_about_audio/loudspeakers_rooms.pdf

edgewound
02-27-2008, 01:49 PM
Since you welcomed all opinions...

I would find it a futile waste hard earned money and efforts to put such big speakers in such a small room unless your goal is to entertain the neighbors.

I'm not trying to be sarcastic....just put things in practicality. To actually enjoy what the 2245 can do, I think you need to be at least 20 feet away from it in a hi-fi scenario. Even a 15" woofer in that small a space is pushing it.

But as Ian said..."we do it anyway". To me a 4345 in a home situation should go in the living room, not the bedroom/small den.

Robh3606
02-27-2008, 02:12 PM
I have heard 4350's in a room almost the same size maybe a little longer. The biggest issue was placement. With cabinets that size, what almost 4 feet wide, you have almost zero options and that goes for Soffit mounting as well. You want to get them away from the side walls, toe them in and have a reasonable distance for the drivers to integrate properly. Clearly the size is working against you. Why not 4430 or a 4435 in a verticle alignment. 4344's possible as well??

Rob:)

rs237
02-27-2008, 02:59 PM
Grateful to all who responded. I have already feared, but wanted to hear your opinions.
@ Rob
No one smaller Speaker should not be, then I must find a bigger room
or 4435 in a verticle alignment....
Perhaps can be room on 4m * 6m (13ft * 20ft) extend.
@ Peter
thanks for the link.
@ Ian
I understood you correctly "square its bad"?
@ edgewound
It would 4m * 6m (13ft * 20ft) better?
@ Andyoz
"Low-freq absorption" yes I have just in my Hartsfield room experienced

regards
juergen

edgewound
02-27-2008, 05:14 PM
For the 4345's...if you can build a bigger room, by all means build it. You can do far more things with more space.

The Floyd Toole room mode calculator puts a 20 foot room at a 28hz room mode...that would be 4345 territory....a little bigger would be even better.

Your 13 foot room would be at about 43Hz. You'd only hear the bass outside the room. What fun is that? It's the same acoustic concept as a car with massive subwoofers inside that can't be heard in the car, but everyone else at the stoplight is ready to kill the SOB.

edgewound
02-27-2008, 05:41 PM
I think the notion of an Americam typical living room is different to Eu or anywhere else. Besides, the average control room is of this size or less but as discussed used an lot of LF absorbtion.



Hey...well these are big American monitors that went into big American control rooms of 450 square feet and larger. Why skimp if you can do it right from the start?

readswift
02-28-2008, 05:57 AM
http://www.gedlee.com/downloads/Cum%20laude.pdf

Geddes on room modes. (Summa is 15" B&C LF and 15" waveguide - "optimised for small rooms" )

rs237
02-28-2008, 07:06 AM
For the 4345's...if you can build a bigger room, by all means build it. You can do far more things with more space.

The Floyd Toole room mode calculator puts a 20 foot room at a 28hz room mode...that would be 4345 territory....a little bigger would be even better.

Your 13 foot room would be at about 43Hz. You'd only hear the bass outside the room. What fun is that? It's the same acoustic concept as a car with massive subwoofers inside that can't be heard in the car, but everyone else at the stoplight is ready to kill the SOB.

hello edgewound,

Ok, I will see if I have the space to 6m (20ft) may extend.

@readswift thanks for the link.

regards
juergen

4313B
02-28-2008, 07:08 AM
Thanks for the link readswift.

http://www.gedlee.com/Summa.htm

Photo from http://www.bradjudy.com/audioblog/rmaf3/

pos
02-28-2008, 07:13 AM
http://www.gedlee.com/downloads/Cum%20laude.pdf

Geddes on room modes. (Summa is 15" B&C LF and 15" waveguide - "optimised for small rooms" )

very interesting reading, thanks!
It looks like the 4430 fits most of the described requirements.
The "over-toed" idea is most appealing

4313B
02-28-2008, 07:42 AM
It looks like the 4430 fits most of the described requirements.Rumor has it that Earl Geddes bought his pair of 4430's from John Eargle. I think he ended up parting them out. I think he also wrote up what he thought was wrong with them from a performance perspective. I can't remember the details now.

rs237
02-28-2008, 09:06 AM
Sorry, I am not so fast. I had to translate everything. Very, very interesting.

regards
juergen

rs237
03-04-2008, 10:14 AM
Hello ,
very interesting reading, thanks!
Did someone more information on this Speaker? Used driver. Information on Refractive sound plug. Which 15 "Woofer JBL would do well 950Hz and even have enough bass in a 4-5 ft≥ Box ?
regards
juergen

Robh3606
03-04-2008, 10:31 AM
Which 15 "Woofer JBL would do well 950Hz and even have enough bass in a 4-5 ft≥ Box ?


2234/2235

Rob:)

readswift
03-04-2008, 11:55 AM
Geddes has a topic at diyaudio.com , recently he said he wont sell the premachined waveguide but gives away the open cell foam in in blocks for 10 USD / cubic feet.
http://www.diyaudio.com/forums/showthread.php?threadid=103872

FYI I checked the B&C woofer it uses, winisd simulator says 2235 has vastly superior bass ... Geddes has subwoofers, in one of his posts he says even 3 or 4 :)

rs237
03-04-2008, 12:02 PM
Hello

thanks rob, thanks readswift. I have a pair 2234 , fresh recont fron Guido:D.

regards
juergen

readswift
03-04-2008, 12:11 PM
I have 4 genuine 2234 , Initially I wanted 4435's but now that I obtained a second pair of 2344 horns I think I go for 4430's . Maybe with foam waveguides too :)

CONVERGENCE
03-04-2008, 04:49 PM
Studio control rooms are not that big . They are acoustic treated. I've seen this new fabric panel which they put on the walls. In the studio itself
velour curtains are sometimes used. You really need a tef analyzer to determine the reverb decay of your room.

.............................

rs237
03-04-2008, 11:56 PM
Studio control rooms are not that big .............................

Hello Convergence,

Yes that was my first thought. But the effort for the room adaptation is probably too large. I will be closer to the Summa.

regards
juergen

Rolf
03-05-2008, 12:11 AM
Hi. In my experience big speakers don't need big rooms if the room is done right.

My 4343B's plays very good in my room witch is about 4,5 x 6,5 meters (14,7 x 21,2 ft).

What to be carefully done is type of furniture, what on the floor, walls and ceiling.

I know I can do more to make it sound even better in my room, but I am actually quite pleased how it sounds, so why bother...:o:

rs237
03-05-2008, 12:22 AM
Hello Rolf,

Thank you for the answer.
Your room is not really small. My space is just 4m X 4m:(.

regards
juergen

Rolf
03-05-2008, 05:05 AM
Hello Rolf,

Thank you for the answer.
Your room is not really small. My space is just 4m X 4m:(.

regards
juergen

Hi. I used to have Paragon in a 3 x 3,5 m for many years ago.:D

pos
03-13-2008, 06:18 AM
Thanks for the link readswift.

http://www.gedlee.com/Summa.htm

Photo from http://www.bradjudy.com/audioblog/rmaf3/

his new website:
http://www.ai-audio.com/products_esp15.html

rs237
03-13-2008, 02:42 PM
his new website:
http://www.ai-audio.com/products_esp15.html


Hello pos,

thanks for the link, I had already sought after, but could not find anything.

regards
juergen

readswift
03-13-2008, 06:24 PM
I wonder if you can build an "ULF" sub like that with his (Geddes) simulator prog , called Speak . Someone has it here?

I have 2x Beyma 18 lx60 I'd rather not sell ( PA plans, hi hi )

readswift
03-23-2008, 07:27 PM
okay, his prog can simulate that kind of subwoofer, I think I spare money on the crossovers (http://audioheritage.csdco.com/vbulletin/showthread.php?t=20491)and buy it :)

meanwhile, there is some talk about wooden enclosure "kits" on the walmart (diyaudio) forum. Maybe I really goin to have these foam horns to play with. Woofers remain unchanged ofcourse , also can listen against 2344's. oh how cool is this :applaud:

CONVERGENCE
03-24-2008, 07:25 AM
This photo of Augspurger monitors at Sound On Sound should give you an idea .Contol room 20' X 21' .

rs237
03-24-2008, 12:54 PM
Hello CONVERGENCE,

thanks for the cool picture.
I think I will be only a 15 "woofer, and a similar Speaker of the Summa build.

regards

juergen

Allanvh5150
03-24-2008, 10:33 PM
Hi Juergen,

My motto about cabinet verse room size is simple. If the cabinet fits in the room, the room is big enough.:)

Akira
03-24-2008, 11:48 PM
Your 13 foot room would be at about 43Hz. You'd only hear the bass outside the room.

I could be wrong but...I believe a dimension of 13' would yield an uninterupted response of 86Hz not 43Hz as the positive and negative phase of the frequency would cut in half your low end response.

FOR THIS REASON: the minimum clearance for a control room is considered to be 18' which yields a response of 63Hz. This btw, is the exact frequency you will find on the original Neve consoles--63Hz, which I don't think is a coincidence since it has since been adopted as standard by many other manufacturers. (63Hz is considered a very musical frequency and the heart of the 'English drum sound' which years later gave birth to what we commonly accept as modern recording techniques)

MORE IMPORTANTLY...This DOES NOT mean you can not hear anything below that frequency! You certainly can hear lower tones but, where control rooms are concerned you want to hear a clear uninterupted low end fundamental as opposed to reflections and harmonics which gain their wave length from bouncing back and forth.

p.s. Soffet mounting is one of the best ways to improve your sound, especially with older 'box' type monitors. Soffet mounting makes the walls disappear as the first sound wave hits you directly. Out of phase back reflection is mostly eliminated. A well designed control room is NOT DEAD; it is neutral. There is a lot of controlled dampening to kill bad reflections combined with live surfaces to keep the recording from sounding dead and to provide an accurate translation of the finished product. This along with soffet mounting makes the speaker 'float' and sound effortless.

Allanvh5150
03-25-2008, 03:19 AM
63Hz is very musical indeed. A 22" inch kick drum is about bang on 63Hz.:)

edgewound
03-25-2008, 06:33 AM
I could be wrong but...I believe a dimension of 13' would yield an uninterupted response of 86Hz not 43Hz as the positive and negative phase of the frequency would cut in half your low end response.


Don't disagree with me...disagree with Dr. Floyd Toole.
http://www.harmanaudio.com/all_about_audio/loudspeakers_rooms.pdf

Doesn't it make sense to have a big room for big speakers...and vice versa?

Akira
03-25-2008, 09:51 AM
Don't disagree with me...disagree with Dr. Floyd Toole.
http://www.harmanaudio.com/all_about_audio/loudspeakers_rooms.pdf

According to FLoyd Toole, the example he gives states that a room 20' long will have a mode @ 28Hz. This is a standing wave and not an uninterupted wave length. Thus his calculations state that the first mode is found by DOUBLING the length of the room. I am referring to minimum dimensions for a properly constructed control room. While I do not know the physics behind it, I have always accepted the wisdom of the recording industry that states 18' is the minimum workable dimension to produce an UNINTERUPTED wave length of 63Hz.


Doesn't it make sense to have a big room for big speakers...and vice versa?
I've always felt that a certain size box is ideal for a certain size room. But, I guess it's like a car. A certain size engine is ideal for a certain size car but, there seems to be an appeal to having an engine that can over power the mass it requires.

Akira
03-25-2008, 09:58 AM
63Hz is very musical indeed. A 22" inch kick drum is about bang on 63Hz.:)
Sounds like you've done some recording! Either that or your old like me and perhaps favor some of the older 'classic' ways of reproducing music.;)

Allanvh5150
03-25-2008, 11:11 AM
Sounds like you've done some recording! Either that or your old like me and perhaps favor some of the older 'classic' ways of reproducing music.;)

Well I'm not so old:) I have done a bit of recording over the years but I have worked mainly with live bands inside. I always treated my work as "in the studio" and we always had a great sound. We always had JBL as well and I have used em all. Allan.

edgewound
03-25-2008, 12:40 PM
I have always accepted the wisdom of the recording industry that states 18' is the minimum workable dimension to produce an UNINTERUPTED wave length of 63Hz.
.

The answer lies in your statement. An UNINTERRUPTED wavelength of 63Hz is 18' (17.93' if you use 1130 ft/sec speed of sound). A smaller room would choke off bass response.

Therefore...to get the full sub-bass response before standing waves have a chance to kick in...the math would dictate that a big room with big volume would be the best practice to house big speakers. A 20Hz room should be at least 113 feet long/wide, preferably asymmetric. Ever
wonder why bigass subwoofers are heard outside of a car's interior? ...like 20, 40,50...200 feet away? Space. Concert engineers would always rather work outdoors sans walls for good reason....He/she don't hafta bother with'em.

But you already knew that;):)

Ian Mackenzie
03-25-2008, 05:33 PM
Edge,

I hate to say but you are talking theory out of your a%^&.

The context of pure theory is often mis applied to make a point.

What actually happens in a real room depends on a lot of issues such as wall constuction/treatment, the exact location of the speaker and this listener.

The size of the loudspeaker incidentally is irrelevent. For example a Carver Sunfire sub is 12 inches square...I guess you call that small and its okay to put it in a small room.

As a matter of fact most studios incorprorate bass traps and other treatments to control standing waves, but as a rule they are not particularly interested in sub terrain base.

The term big speaker usually inmplies big woofer. Big woofers have higher power anding and lower distortion, that is their key advantage. They o not necessarily go lower than a smaller woofer.

edgewound
03-25-2008, 05:51 PM
Edge,

I hate to say but you are talking theory out of your a%^&.

The context of pure theory is often mis applied to make a point.

What actually happens in a real room depends on a lot of issues such as wall constuction/treatment, the exact location of the speaker and this listener.

The size of the loudspeaker incidentally is irrelevent. For example a Carver Sunfire sub is 12 inches square...I guess you call that small and its okay to put it in a small room.

As a matter of fact most studios incorprorate bass traps and other treatments to control standing waves, but as a rule they are not particularly interested in sub terrain base.

The term big speaker usually inmplies big woofer. Big woofers have higher power anding and lower distortion, that is their key advantage. They o not necessarily go lower than a smaller woofer.

Read my post again before your wine soaks in, Ian.

First of all...my post said "best practice" , which is purely based on the physics of very long soundwaves, and Akira's post about 63Hz and 18' prove that.

This thread started life as recommendations for a room addition that will house huge monitors that go very low...not the proper way to build a recording studio control room. I also pointed to Dr. Floyd Tooles' Room Mode calculator for reference. Aside from that, big ass speakers shouldn't be used as headphones...my opinion, of course.

Most all good practices start with theory...and then get compromised due to practicality.

Yeah...a Sunfire subwoofer is a 12" cube that moves gobs of air. Would you rather be in a broom closet or a Great Room listening to it.

I'll take the Great Room, thanks very much.

And BTW...I only let you insult me like that because were friends.;):p

Allanvh5150
03-25-2008, 10:28 PM
Just to add something else, what if our speaker cabinet is in an anechoic chamber where there are no standing waves whatsoever. Then, theoretically, would it make any difference what the size of the room was?

Mr. Widget
03-25-2008, 10:47 PM
Just to add something else, what if our speaker cabinet is in an anechoic chamber where there are no standing waves whatsoever. Then, theoretically, would it make any difference what the size of the room was?Nope. Theoretically.

That said, I don't know if there are any anechoic chambers big enough to be "flat" below 25-30Hz.


Widget

John
03-25-2008, 11:11 PM
big ass speakers shouldn't be used as headphones...my opinion, of course.


Don't tell the owners in Japan:D

rs237
03-26-2008, 01:06 AM
Hello
Very interesting discussion. Thank you to all those who are involved. I have a lot of new information. When bass Proplem I agree with Ian, the problems, the space regardless of whether I make a small or big box use.
But I am in the Summa, in this Tread was called love. It will be my next project. I have 2452HSL and 2234, and will build a horn itself.

regards

juergen

Allanvh5150
03-26-2008, 01:41 AM
Nope. Theoretically.

That said, I don't know if there are any anechoic chambers big enough to be "flat" below 25-30Hz.


Widget

I visited one of my machinery manufactures in Italy a few years ago. They had an anechoic chamber big enough to park a dump truck in. They even test whole ferrari's in it from time to time. When you talk you get the feeling that you have your head in a bag. The sound just seems to stop right in front of your face. Very freaky.

cooky1257
03-26-2008, 02:39 AM
A few things intrigue me surrounding this issue.
The first is that once you open a door or window, what's happened to the 'longest' room dimension? What if you have a fireplace/chimney?
What's happening on the 'other' side of the cone-ie that much smaller room called the cabinet?What about transmission through walls/floors etc-I have no trouble hearing/feeling the infrabass of a thunder clap from inside my living room.

Ian Mackenzie
03-26-2008, 03:02 AM
Hello
Very interesting discussion. Thank you to all those who are involved. I have a lot of new information. When bass Proplem I agree with Ian, the problems, the space regardless of whether I make a small or big box use.
But I am in the Summa, in this Tread was called love. It will be my next project. I have 2452HSL and 2234, and will build a horn itself.

regards

juergen

Edge, was pointing to post 39.

As we said in the first few posts and as discussed with Jurgen the notion of bass issues of big speakers for average size home living room use is not the concern.....its where you can put them to make best effect overall.

Listening distance, space between enclosures and the rear wall is a problem with large boxes.

In contrast I could fire up a pair of LSR32 with the matching sub and the problems Edgewound is on about would still exist but you will have more flexibility in finding the best position for problems like early reflections to get the best imaging.

I think that is why Jurgen likes the Suma as it is room friendly design.

Small to medium rooms tend to have more bunched up room modes below 300 hertz but that is not the end of the world. You can incorporate acoustic treatments and some careful eq to ease those issues if they respresent a problem where you want to sit and listen. Careful location of the enclosures relative to the room boundaries will help control those room modes and manipulate room gain below 100 hertz if you feel that last couple of octaves are important to you.

As is often the case arm chair critics in these types of discussions forget that they talking about the real practically of someone's home. Their desires and all the other considerations, like the spouse, other furniture and something to sit on are just if not more important than what is printed on a white paper or outspoken, insensitive, jaded opinions.

There are less options with large enclosures, its that simple.

In contrast large modern rooms with broad, flat hard surface like a modern American living room are a serious PITA for high quality sound reproduction. They have less pronounced room modes but the problems associated with all those large flat surfaces play havoc with the rest of the audio spectrum above 500 hertz. Controlling those issues without getting a divorce is difficult and expensive. Depending on the room construction bass heard outside room may or may not be an issue.

Ducatista47
03-26-2008, 09:21 AM
As one who faces these concerns every time I listen to music, I must say that was a nice summation, Ian.

I was thinking that building a room from scratch would eliminate the issue of odd shaped rooms, but then I remembered this: http://audioheritage.org/vbulletin/showpost.php?p=137039&postcount=10
So who knows?

I wish it were possible to soffit mount my 4345 pair, but in two words, forget it.

Using any speaker, large or small, as "Headphones" has one advantage. Getting closer tends to distance the room from the equation. The direct sound is louder in relation to the reflections, so they diminish in importance.

Clark

readswift
05-17-2008, 10:59 AM
hi, over diyaudio, dr. Geddes considers doing a run of his 12" - 15" waveguides (and molded baffle like Ai ESP12 ) !
I think we reach the dozen amount required anyway, but I hint this info for you to know. Looks to be cool alternative of 2344 for instance:)

oh the link: http://www.diyaudio.com/forums/showthread.php?threadid=122318&goto=newpost

JBL 4645
05-17-2008, 04:03 PM
My room is more or less within rs237. Control room well I am using JBL Control series. :D

Iíve done something rather different taken a frequency response waterfall graph chart of my voice while producing a deep tone the word (one 1) or a tonal sine wave with the human voice. The ECM8000 was placed within 6Ē while I listened to my voice (one 1) and haring the reverberation reflecting off the corner with slight delay and then decaying. Iím guessing the decay is around 1 to 1.5 or less, but itís audible that much I can tell.

So how do you go about use a microphone and testing the room with frequency sweep or sine wave spot frequency, to get a rough 100% on the reverberation domain time limit?

Now Iíve tried this against fabric material like the drapes in the front of the room and there is less reflectivity.

http://i282.photobucket.com/albums/kk279/SpectrumsubbassLFE13417/Myvoiceone1.jpg

Doesnít amplitude of the frequency increase further with more power and that is probably why neighbours can hear often hear the deep pulsing tone travelling the length from ones home to the next?

johnaec
05-17-2008, 04:33 PM
...a frequency response waterfall graph chart of my voice...So is the time domain the vertical axis in your graphs? Since it's "waterfall", does that mean time starts at the top in the graphs?

Edit: I was just looking at one of your graphs in your DVD thread and see that time starts at the bottom.

John