Woofer for the MBOW1 3-way ?

[annael]

Hello,

Is there a direct replacement for the 850146 woofer that is now discontinued?

[Pete Schumacher ®]

> Hello,

> Is there a direct replacement for the 850146
> woofer that is now discontinued?

Not an exact replacement.

However, Peerless's SLS line would likely be a great substitute. The XO for the woofer would need modification, but it certainly has the response smoothness, sensitivity and bandwidth to accomplish the goal.

[dennismurphy]

> Not an exact replacement.

> However, Peerless's SLS line would likely be
> a great substitute. The XO for the woofer
> would need modification, but it certainly
> has the response smoothness, sensitivity and
> bandwidth to accomplish the goal.

Would that were true. I tried the 830668 some time ago in an attempt to find a decent replacement for the 850146. The 830 has a very rough roll-off profile and doesn't go as deep. I couldn't achieve a decent 2nd order slope with it, and it's been gathering dust ever since. I gotta say--the decision to drop the 850146 has to rank up there with the Edsel and New Coke as testimonials to corporate dumbness. Booooooo Peerless.

[Pete Schumacher ®]

> Would that were true. I tried the 830668
> some time ago in an attempt to find a decent
> replacement for the 850146. The 830 has a
> very rough roll-off profile and doesn't go
> as deep. I couldn't achieve a decent 2nd
> order slope with it, and it's been gathering
> dust ever since. I gotta say--the decision
> to drop the 850146 has to rank up there with
> the Edsel and New Coke as testimonials to
> corporate dumbness. Booooooo Peerless.

I LOVE the 850146 and have a pair sitting here waiting for the right project.

Have you found a suitable replacement for the 850146 outside of Peerless?

[johnnail]

> Would that were true. I tried the 830668
> some time ago in an attempt to find a decent
> replacement for the 850146. The 830 has a
> very rough roll-off profile and doesn't go
> as deep. I couldn't achieve a decent 2nd
> order slope with it, and it's been gathering
> dust ever since. I gotta say--the decision
> to drop the 850146 has to rank up there with
> the Edsel and New Coke as testimonials to
> corporate dumbness. Booooooo Peerless.
Dennis, what do you mean by "it has a rough roll-off profile"...exactly? I have simulated both woofers with driver response files in the specified 2 cu.ft. box....and they appear to be nearly identical with a few exceptions. First exception...the SLS unit has some peaking happening in the 2K region...which for a 3 way, wouldn't really be an issue. Second exception...the SLS appears to be more suited to a slightly larger sealed box. To be fair, I haven't tried either woofer in real life...and I only have the specs and response files provided by my database. But, as to the SLS not going as deep. Both woofers have an identical F3 in the same box....BUT the SLS has a 2.7dB peak above Fb....due to it's higher resulting Qtc. So, if you switch to an aperiodic loading by using a Variovent, that peak disappears down to a paltry .75dB...and the overall Qtc drops quite a bit....to .61 . Very similar to the 850146's Qtc .59 in the same volume with no variovent.
The F3 differences between the two drivers are about 2 hz.....the 146 at 46hz, the SLS at 48hz....both, with room gain, reach to about mid 30's F3.....34hz for the 146, 36hz for the SLS. Again, only about 2hz difference. What I wonder is whether or not the supplied database specs I have are truly representative of the real drivers....Do you have actual measured T/s Parameters of both drivers so that I can update my database for accuracy on this?

John

[dennismurphy]

I'll send you my SPL and impedance measurements taken in the MB0W1 3-way's 2 cu ft box. The bass reach wasn't the real issue. There was around a 2 Hz difference--not a biggy. The SLS just wasn't nearly as smooth. That was obvious when you listened full range. The Old Peerless was actually enjoyable, while the SLS was highly colored. The 2nd order crossover didn't eliminate this entirely. There's a Vifa buyout at Madisound (or PE?) that someone just sent me. It seems to be much better, but I haven't had a chance to work with it much.

[unknownuser]

Provided Link: http://http://www.tymphany.com/datas...view.php?id=37


Have the specs for the 668 changed?

F3 in the low 50's ?


(Originally posted by: 2K)

[unknownuser]

<A HREF="http://www.tymphany.com/datasheet/appview.php?id=37">http://www.tymphany.com/datasheet/appview.php?id=37</A>


(Originally posted by: 2K)

[johnnail]

> Have the specs for the 668 changed?

> F3 in the low 50's ?
Hi....you need to read the post again..... F3 in the mid to upper 40's...but if minimal room gain is figured into the mix, then mid 30's will be about the bottom reach.
The "50's" that you interpret must be the QTC of the box. This is not the F3....this is the Q of the box. Accroding to the specs I have on the 850146 woofer, in a 2 cu.ft. sealed box with average stuffing amount (1.5" fiberglass on all walls) the overall QTC of the finished system would be .590. The F3 would be about 46hz....with minimal room bass gain, the bottom extends to the mid 30's. You must not have read the post carefully.

John

[unknownuser]

> Hi....you need to read the post again.....
> F3 in the mid to upper 40's...but if minimal
> room gain is figured into the mix, then mid
> 30's will be about the bottom reach.
> The "50's" that you interpret must
> be the QTC of the box. This is not the
> F3....this is the Q of the box. Accroding to
> the specs I have on the 850146 woofer, in a
> 2 cu.ft. sealed box with average stuffing
> amount (1.5" fiberglass on all walls)
> the overall QTC of the finished system would
> be .590. The F3 would be about 46hz....with
> minimal room bass gain, the bottom extends
> to the mid 30's. You must not have read the
> post carefully.

> John

Looking at the peerless 830668, in the link, the suggested box size of 40L with the specified stuffing F3 or what they call f-3Db is 53 HZ. Looking at the supplied curves for rolloff and transient response I say Qtc is about .707.

I've measured the 850146 in 60L sealed and gotten an F3 of 43-44 Hz.

I've looked at the 830668 and its 12" sibling as a replacement/upgrade for the 850146 but I can't get past the highish F3. The SLS frequency response certainly looks clean enough for lower order crossover use in the 200-400 Hz range.


(Originally posted by: 2K)

[johnnail]

> Looking at the peerless 830668, in the link,
> the suggested box size of 40L with the
> specified stuffing F3 or what they call
> f-3Db is 53 HZ. Looking at the supplied
> curves for rolloff and transient response I
> say Qtc is about .707.

> I've measured the 850146 in 60L sealed and
> gotten an F3 of 43-44 Hz.

> I've looked at the 830668 and its 12"
> sibling as a replacement/upgrade for the
> 850146 but I can't get past the highish F3.
> The SLS frequency response certainly looks
> clean enough for lower order crossover use
> in the 200-400 Hz range.
I saw the posted suggestions on the Tymphany site...and I wouldn't necessarily go by what you are seeing. You can achieve that same Qtc using a variovent in that sized of box.... Please take note of their suggested alignment and notice that there is no stated Ql or Qa of the box model listed....I checked their posted specs against what I have in my database and they are the same specs to the decimal....yet the recommended standard sealed box volume for Qtc .707 with adequate fill is going to be about 2.3 cu.ft. with F3 in low 40's....almost identical to 2 cu.ft sealed 850146 alignment. The only way I could get the highish F3 that they state, and keep the Qtc to about .707 was to use a Ql of 2.7 instead of the usual 15-20. This would indicate to me that they are maybe using a Scanspeak variovent in the alignment. I frequently model Scanspeak variovents using the setting of Ql at 3. With my software I let the software just the Ql and volume...using standard Qa of 10...which is sealed with 100% fill fiberglass. Volume turns out to be 2.3 cu.ft. and Ql is about 17.7....final Qtc of .707....F3 of 41hz.

Just think that you should actually try it out before you just dismiss this driver due to some offhanded alignment that obviously is incomplete in the specifics.

John

[johnnail]

> Would that were true. I tried the 830668
> some time ago in an attempt to find a decent
> replacement for the 850146. The 830 has a
> very rough roll-off profile and doesn't go
> as deep. I couldn't achieve a decent 2nd
> order slope with it, and it's been gathering
> dust ever since. I gotta say--the decision
> to drop the 850146 has to rank up there with
> the Edsel and New Coke as testimonials to
> corporate dumbness. Booooooo Peerless.

Dennis, what do you expect? When competent designing is replaced by corporate greed and profit-margin economics....when the decisions are being made by "board members" instead of "design teams", things like quality and excellence get kinda lost in the background. In the past, Peerless has always been known for their drivers that deliver deep, powerful bass in compact package...smaller than 12" drivers that reach way down in the depths and deliver the goods. They had this trait fine-tuned with the CSC and CSC-x line.....since then I haven't seen a decent low-bass delivered from any of their drivers until you move into the SLS, XLS, XXLS, etc and stick to 10" or larger. The days of the 'impressive bass response" from the 5.25" to 8" drivers from them are gone....maybe they might return, but probably not gonna happen as long as members of a board are more concerned with bottom lines than quality and reputation.

I like the materials they have moved to....with regards to the nomex cone materials and such...but note that the 7" drivers that replaced the 6.5" CSC and CSC-X lines....please note that while the overall diameter got a little bigger, the F3's of the resulting alignements got higher....instead of going a little lower.
A similar change has happened over at SEAS, but fortunately for us DIYers, the resulting increase in diameters of the drivers and redesign of the motor has resulted in a more impressive driver performance......WAY TO GO SEAS!.....NOT a decrease of bass performance over whatever it is they think they gained sacrificing the bass performance.. I clearly don't know what that would be, though. Not a clue.
As to the sale driver at madisound/PE....would that be the 10" treated paper cone Audax unit that is on clearance at PE? If so, the xmax is not as impressive as the old Peerless unit.

John

[unknownuser]

> I saw the posted suggestions on the Tymphany
> site...and I wouldn't necessarily go by what
> you are seeing. You can achieve that same
> Qtc using a variovent in that sized of
> box....

The data sheet did say sealed box not aperiodic. I have to take the info at face value. They are trying to market this as a subwoofer right? Why would they misrepresent F3 10 Db the wrong way?


(Originally posted by: 2K)