• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

SpeakerLab 7

Crossover points are a great subject for debate... for a true sub woofer that does seem a little high but Graebener was a great designer so he must have had his reasons. The original 7's and the super 7's had the two woofers rolling off at 350hz.... Same with the 50's .
SC is just my initials and a nod to one of my favorite cars the sc427 Cobra....
 
I love these Speakerlab posts! The decision as to which version of the larger classic models to build given all of the drivers and crossovers sitting idle in the garage has yet to be made. Will - one of these days I will give you a call and we will figure this out! :yes:
 
I got my mint 6's for free and they are delightful ! Not interested in looking any further for speakers on my main system pushed by a Jolida 302B running GL KT77's.

Mike
 
markdi said:
I think my version was the last - kinda sad.
Speakerlab should start back up

I wonder how they stack up compared to the older 7's and the horny 7's :D
I think my version was the only version with a port and a dome tweeter
Rear firing 12 inch
Rear port
Were they originally tilted back somehow ?
Click to expand...

sc427 said:
The DAS7 is a 4 way speaker.... The original horn 7, the 7wa, and the super 7 are all 3 ways with the 10" and 12" drivers run together. The DAS7 rolls the 12" off at 180hz......It is also the only ported one of the bunch.
Click to expand...

sc427 said:
Crossover points are a great subject for debate... for a true sub woofer that does seem a little high but Graebener was a great designer so he must have had his reasons. The original 7's and the super 7's had the two woofers rolling off at 350hz.... Same with the 50's .
SC is just my initials and a nod to one of my favorite cars the sc427 Cobra....
Click to expand...

All of this brings up an interesting (to me anyway) question or 2. The first 3 generations of S7, all 3-way, had their 2 8-ohm woofers in parallel, so 4 ohms in the woofer section. The various horns/ribbons and horns/6.5" mids were 8 to 16 ohms but the nominal overall impedance is 4 ohms because of those parallel woofers drawing most of the load. OK, you all know that but bear with me.

But the Das-7 and later S7 are 4 way, 4 ohm nominal speakers. I don't see how you can run 2 8-ohm woofers in parallel and still have different crossover points. Can that be done? See where I'm going? Looking in the Speakerlab catalog for 1986 and the pamphlet & driver list there are no 4 ohm drivers of any sort that I can see.

The DAS-7 has an 8-ohm 1" dome and a 6.5" 8-ohm mid, both crossed 3rd-order (so 18db/octave) at 5khz, an 8(?)-ohm 10" woofer crossed 2nd order (12db/octave) at 350hz, and an 8(?)-ohm 12" woofer crossed 1st 0rder (6db/octave) at 180hz. So how are they getting a 4 ohm nominal for the assembly? (Interesting progression of filter orders.)

The only way that I see that that could work is if they are using the W1088P 8-ohm dual voice coil 10" and W1244P dual voice coil 12" that are in the raw driver list and running the dual voice coils of each woofer in parallel. You could get 2 individual 4-ohm woofers that way. I think. How else could they be making this work? Is there a way to cross 2 8-ohm woofers at different points and still have them run in parallel for an 4-ohm load?

Cheers,
James
 
Bratwurst7s said:
I replaced the original Foster ribbons with Visaton ribbons. Very nice improvement.

Cheers,
James
Click to expand...

Mine are so new I would cry to cut them open.:banana:

So seriously I am actually very temped by the Visatons but as my listening space is not ideal ( there are 3.5 feet off the ground) thus I am not sure the change would be as good as it could if set up properly
 
yaya97 said:
Mine are so new I would cry to cut them open.:banana:

So seriously I am actually very temped by the Visatons but as my listening space is not ideal ( there are 3.5 feet off the ground) thus I am not sure the change would be as good as it could if set up properly
Click to expand...

I agree. You just got them. Why rush to change them before you have had time to get to know them? Besides, it doesn't sound like you have tried flipping them on their heads yet. No joke, I think that you would be pleasantly surprised. Gotta think outside the box so to speak. :D

Besides, the Visatons are darned expensive. In Dollars they would probably be $200 each. That's a lot of cases of beer.

Cheers,
James
 
If they are dual voice coil drivers then they only have one set of terminals per woofer

Were my sevens originally tilted back somehow ?
 
mikejennings said:
I got my mint 6's for free and they are delightful ! Not interested in looking any further for speakers on my main system pushed by a Jolida 302B running GL KT77's.

Mike
Click to expand...
If I was smart I would quit buying speakers and stuff
My dad says sell sell sell
 
markdi said:
If they are dual voice coil drivers then they only have one set of terminals per woofer

Were my sevens originally tilted back somehow ?
Click to expand...

OK. Interesting. Deepens the mystery for me. Then I can only guess that it's possible to run the woofers in parallel and still at different crossover points.

I can't tell you exactly if your 7s were tilted. I do know that mine came with a very rudimentary stand that did tilt them back about 5°.

Cheers,
James
 
Bratwurst7s said:
All of this brings up an interesting (to me anyway) question or 2. The first 3 generations of S7, all 3-way, had their 2 8-ohm woofers in parallel, so 4 ohms in the woofer section. The various horns/ribbons and horns/6.5" mids were 8 to 16 ohms but the nominal overall impedance is 4 ohms because of those parallel woofers drawing most of the load. OK, you all know that but bear with me.

But the Das-7 and later S7 are 4 way, 4 ohm nominal speakers. I don't see how you can run 2 8-ohm woofers in parallel and still have different crossover points. Can that be done? See where I'm going? Looking in the Speakerlab catalog for 1986 and the pamphlet & driver list there are no 4 ohm drivers of any sort that I can see.

The DAS-7 has an 8-ohm 1" dome and a 6.5" 8-ohm mid, both crossed 3rd-order (so 18db/octave) at 5khz, an 8(?)-ohm 10" woofer crossed 2nd order (12db/octave) at 350hz, and an 8(?)-ohm 12" woofer crossed 1st 0rder (6db/octave) at 180hz. So how are they getting a 4 ohm nominal for the assembly? (Interesting progression of filter orders.)

The only way that I see that that could work is if they are using the W1088P 8-ohm dual voice coil 10" and W1244P dual voice coil 12" that are in the raw driver list and running the dual voice coils of each woofer in parallel. You could get 2 individual 4-ohm woofers that way. I think. How else could they be making this work? Is there a way to cross 2 8-ohm woofers at different points and still have them run in parallel for an 4-ohm load?

Cheers,
James
Click to expand...

According to Paul the 12 rolls off from 180hz and down not up. So the amplifier sees the impedance of both woofers at lower frequencies.
 
sc427 said:
According to Paul the 12 rolls off from 180hz and down not up. So the amplifier sees the impedance of both woofers at lower frequencies.
Click to expand...

OK. Let me see if I'm understanding this correctly. Both woofers have an upper crossover point of 350hz, above which they drop 12db/octave. The 10" is free to run as low as it can, rolling off at the lower end where it's inherent limits are. And the 12" has a lower limit of 180hz, below which it drops off at 6db/octave. Is this correct?

Cheers,
James

edit: What throws me off about that answer is that the '95 catalog that I have describes the 12" as a subwoofer.
 
Last edited:
Bratwurst7s said:
OK. Let me see if I'm understanding this correctly. Both woofers have an upper crossover point of 350hz, above which they drop 12db/octave. The 10" is free to run as low as it can, rolling off at the lower end where it's inherent limits are. And the 12" has a lower limit of 180hz, below which it drops off at 6db/octave. Is this correct?

Cheers,
James

edit: What throws me off about that answer is that the '95 catalog that I have describes the 12" as a subwoofer.
Click to expand...

Could my sevens be newer than 92 ?
 
markdi said:
Could my sevens be newer than 92 ?
Click to expand...

Afiak the first year for the DAS lineup was 1986, at least their '86 catalog opening statement announces the DAS as a new series. I have no other info till the '95 flier that I have. There they are called the SL-7 but as far as I can tell are basicly unchanged with regards to specs.

However, the available mids and woofers model numbers in the catalog raw driver lists are different, so perhaps by '95 they were being sourced differently. I have a hunch that by '95 at least some of their drivers were being sourced from Goldwood. I know that the mids that they sold me a few years later were Goldwoods.

Facts regarding Speakerlab stuff in that time period are very few and far between. Mabye sc427 can magic some info from Paul. :D

Cheers,
James
 
markdi said:
So they could be from 86 to 95

I guess i read wrong on the speakerlab site
Click to expand...

Sometime between '86 and '95 the name changed from DAS-7 to SL-7. The speakers themselves appear to be the same, but only from reading what I can find in the catalogs. So if your 7s are marked DAS-7 then they are from sometime in that "sometime between" period. I have no idea when the name change took place. Knowing that would help narrow it down.

All I did was to copy all of the catalog pdfs that I could find directly from the Speakerlab site and start reading them. I make no claims to know everything, or very much at all really. I'm just searching for the rainbow.

Cheers,
James
 
You must log in or register to reply here.
Back
Top Bottom