Focal Twin 6's and soffit mounting

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Funktion
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Focal Twin 6's and soffit mounting

Post by Funktion »

Allright..

As this is my absolute favorite pair of speakers, I don't intend on switching when the time comes to build my place.

So now I'm wondering if anyone has any experience with soffit mounting said speakers?

The problem I see with these speakers is that the drivers are actually not flush with the speaker cabinet, but are a cm or two deep from the edges of the rest of the cabinet.

Is that a big enough problem to make the speakers not suitable for soffit mounting?

Also, I'm using the Sub 6 along with the Twins. I've seen in some pictures that some people have also flush mounted their subs.. Is there any real use to doing this, and is it doable with the Sub 6?

Thanks in advance.
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Re: Focal Twin 6's and soffit mounting

Post by gullfo »

given they are ported on the front even with the varying shape to the cabinet edge and possibly the inset, it should be possible to soffit mount them. this might be a question best posed to the manufacturer in terms of understanding the inset in a soffit mount and if taking the edges down to make it truly flush is an option (most likely voids the warranty). on the sub, soffit mounting is an option but most often you let them float, especially if you're only using one.
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Re: Focal Twin 6's and soffit mounting

Post by Soundman2020 »

Also, I'm using the Sub 6 along with the Twins. I've seen in some pictures that some people have also flush mounted their subs.. Is there any real use to doing this, and is it doable with the Sub 6?
Personally, I wouldn't bother soffit mounting subs. There isn't really much point to doing so. Just put it up against the front wall, around the middle, and you should be fine.

( IMHO. Others might disagree... )

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Funktion
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Re: Focal Twin 6's and soffit mounting

Post by Funktion »

gullfo wrote:given they are ported on the front even with the varying shape to the cabinet edge and possibly the inset, it should be possible to soffit mount them. this might be a question best posed to the manufacturer in terms of understanding the inset in a soffit mount and if taking the edges down to make it truly flush is an option (most likely voids the warranty). on the sub, soffit mounting is an option but most often you let them float, especially if you're only using one.
Yeah, I would only be doing it to match the speakers mounting visually.. I'm a bit of - how do you say it - aesthetics freak. :P

EDIT: However I just realized that the sub is rear ported, so if I understand correctly it would be detrimental to the sound to flush mount it.
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Re: Focal Twin 6's and soffit mounting

Post by gullfo »

rear ports don't necessarily disqualify it, its more that a single sub in a room needs to find the right spot. two subs and you're more likely to be successful in soffit mounting them with the caveat that a number of aspects have to be considered because of the LF involved and your soffit structures etc.
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Re: Focal Twin 6's and soffit mounting

Post by Funktion »

gullfo wrote:rear ports don't necessarily disqualify it, its more that a single sub in a room needs to find the right spot. two subs and you're more likely to be successful in soffit mounting them with the caveat that a number of aspects have to be considered because of the LF involved and your soffit structures etc.
Ah, I see.

Thanks for clearing that up!
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Re: Focal Twin 6's and soffit mounting

Post by Lionzeye »

I know this is an older thread but what the heck. I am considering the same set of speakers (not $10k but pro rated and sound pure) and soffit mounting them as well. Would be cool to see more discussion on this, but maybe the reason is, is that they are good monitors, and most speakers have a better performance when soffit mounted. So, maybe in this case no news is good news! Anyone find out about the possible warranty void Gulfo mentioned? Maybe these are not the best speakers to soffit mount if they have to be modified (besides relocating the back power/control panel for easy access to the front of the soffit).
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Re: Focal Twin 6's and soffit mounting

Post by Eric Best »

First, speakers that are designed for flush mounting perform better when flush mounted. If speakers are not designed for flush mounting they have to be appropriately compensated when flush mounting or you will have a 6dB boost that start a at the baffle step frequency. This is from an earlier post that I made in one of the stickys about flush mounting.
Eric Best wrote:I know it is an old post, but I decided that there were some unanswered questions from this thread about baffle step compensation.

Here is a response graph of a single driver in an enclosure on an infinite baffle (i.e. flush mounted)

Image

If that speaker in that enclosure is mounted on a 7" baffle the bass response will drop like this at about 650hz.

Image

So when the crossover is designed for this speaker a low pass filter is created that will drop the sensitivity of the speaker from 86dB to 80 dB, you lose 6dB of efficiency to flatten out the bass.

So when you flush mount a speaker your bass response will look like this.

Image

Just for comparison sake here is the some driver on an 18" baffle. Notice the difference of where the -6dB shelf occurs, about 250hz.

Image

The formula to determine where the compensation takes place is below.

f3 = 4650/x where x is the baffle width in inches.

So for the 7" baffle we used you have 4650/7=651.43hz.

The Focal has a low shelf switch set at 150hz, the filter for flush mounting should be somewhere between 500 - 600hz depending on the narrowest width of the baffle and the formula above. You would need some other compensation such as Barefoot's baffle step compensation filter if you plan on flush mounting.
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Re: Focal Twin 6's and soffit mounting

Post by Lionzeye »

Wow, I am glad I asked. Been real busy with family and work but I looked at the test results briefly and it sure is eye opening. These are important numbers here and would like to do more research an the subject to make sure I make the best decision based on science, not opinions. Thanks Eric for the science, it is crucial! be back hopefully soon! :D
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Re: Focal Twin 6's and soffit mounting

Post by Lionzeye »

Eric, I have had a little more time to look over the information you have provided, and in conclusion to the frequency response graphs, I would make my own best educated decision to not flush mounting the focal twin 6's as they are not true flush on the baffle, unless the speaker baffle is modified thereof, and would require a step compensation filter to make up for gain. It makes sense to purchase (if we can afford) a set which has been designed for soffit mount.

Eric's Posted formula:
The formula to determine where the compensation takes place is below.

f3 = 4650/x where x is the baffle width in inches.

So for the 7" baffle we used you have 4650/7=651.43hz.
Thanks so much for the formula and of course graphs! :D
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Re: Focal Twin 6's and soffit mounting

Post by Eric Best »

The circuitry to make this is pretty simple if you have someone who has some experience with electronics.

This was designed by Barefoot http://barefootsound.com/homerecording_ ... single.gif
The discussion about it is here. http://www.johnlsayers.com/phpBB2/viewt ... f=12&t=766
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Re: Focal Twin 6's and soffit mounting

Post by Lionzeye »

The circuitry to make this is pretty simple if you have someone who has some experience with electronics.
Dumb question maybe, but I have had past experience in circuits and electronics for a year in college and did very well, but that was quit some time ago now, and haven't built a circuit since, but of course good experience soldering, wiring, etc. Is that what you refer to as some experience?? :wink:
The Focal has a low shelf switch set at 150hz, the filter for flush mounting should be somewhere between 500 - 600hz depending on the narrowest width of the baffle and the formula above. You would need some other compensation such as Barefoot's baffle step compensation filter if you plan on flush mounting.
I actually just realized I made an error and was referring to the Focal solo6 not the twin 6, but the only difference is x = width, due to smaller box for one driver, is that correct?

We might end up spending much less than the solo6 anyways. We want to upgrade a notch from Yamaha NS80. We may just stick with something in our realistic price range, such as Adams A7. Anyways, sorry off track from this thread, that will be saved for a gear thread. Unless we are referring to speakers that are designed for flush mount. Hey, naturally begin using the term "flush mount" and not "soffit mount". :lol: haha it's seems more correct.

Thanks so much
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Re: Focal Twin 6's and soffit mounting

Post by Eric Best »

Dumb question maybe, but I have had past experience in circuits and electronics for a year in college and did very well, but that was quit some time ago now, and haven't built a circuit since, but of course good experience soldering, wiring, etc. Is that what you refer to as some experience??
That is more than I ever had and I have built a lot of circuits now. My degrees in math and a minor in physics sure have helped make it easier to learn!

The A7s low shelf is +/-6dB at 300 hz, for a 7" baffle for flush mounting it should be at about 550hz. I'm not really sure about flush mounting nearfield monitors anyway. I kind of feel like a monitor with as much praise as this one has received that I wouldn't want to mess with it by flush mounting it. I would like to hear from someone who has flush mounted the A7 or other nearfields and how mixes translated, not about how great the low end sounded.
Hey, naturally begin using the term "flush mount" and not "soffit mount". :lol: haha it's seems more correct.
Glad you noticed, I tried not to be too passive aggressive about that! :)
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Re: Focal Twin 6's and soffit mounting

Post by johan_rambo »

Near field to me is any configuration of speakers where the distance LP to speaker is less than 2 meters, and I'd say 2 meters is even pushing it. Much more than this and the room (aside from the usual 1st reflection points which must be handled even for the nearfield configuration) begins to have more impact on the sound thereby diminishing the advantages of nearfield monitoring.

I'll compromise with you and say "mid-field", or we could just use the term "Bigs" : :shot:


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Re: Focal Twin 6's and soffit mounting

Post by Soundman2020 »

Near field to me is any configuration of speakers where the distance LP to speaker is less than 2 meters, ...
Actually, it doesn't depend on what you happen to think is a good distance. Below I re-quote from a thread of just a couple of months back:

Actually, it all depends on what type of "near field" you are talking about! There are two types, and two definitions. If you are just talking about naked speakers in open air (no room) then there are equations for calculating what "near field" and "far field" mean for that speaker, based on the dimensions. But basically the transition from near to far occurs at roughly 7 times the largest dimension of the speaker face. So a 12 inch tall speaker will transition roughly 7 feet from the speaker face. That is purely a speaker-related issue, and has nothing to do with the room.

But there is also "near field" and "far field" for the room itself, independent of the speaker and that too can be calculated and measured. It occurs at the point where the sound field transitions from direct to reverberant, or from 6db to 3dB change per distance doubling. That is referred to as the "critical distance" for the room, and is not related to the speaker itself: any speaker will give the same result, since it it totally a room issue, based on volume, absorption, etc.

So the question is, what happens to the near-field / far-field of the speaker, when you put it in a room with its own near-field and far field? That's the million dollar question that nobody knows how to answer. But basically, the room wins. Regardless of the speaker, the room has its own near and far field. And in a small room, by definition there is no far field, since it is frequency dependent! You simply cannot have a statistical reverberant field in a small room, because the wavelengths do not fit. That's why RT-60 measurements for small rooms really are not RT-60 measurements at all! They are more accurately just modal response measurements. In order to have a fully reverberant field, you need a room where the dimensions are at least 7 times the shortest wavelength that you want to be reverberant. Do the math: that's a very large room at 20 Hz.!!! :shock: That's why you'll see folks say that small rooms have no reverberant field, and no RT-60. So they also have no far field.

In other words, the terms "near field" and "far field" as applied to speakers are pretty meaningless, since it is the room that determines the actual response, and there simply is no such things as a "far field" in the vast majority of home studios.

And of course "mid field" is pure marketing hype: Technically, there is no such thing.

There was a great discussion about this point over at Studio Tips a few years back, with guys like Eric Desart, Rod Gervais, Bob Golds and Bert Stoltenburg. I have a link to that somewhere, but I couldn't find it.... Anyway, as I recall their basic conclusion was that nobody really knows what a "near field" or "far field" speaker is! There's no definition, so anyone can build a speaker and call it whatever they want. Those names are much more marketing-oriented than actual technically valid specifications, especially considering that it is the room itself that has the last word, and no home studio actually has anything even remotely resembling a far field anyway.
Link to that thread:
http://www.johnlsayers.com/phpBB2/viewt ... pe#p120165




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