Anyone have project plans utilizing the Peerless 831882 (5.25") Exclusive Driver?

[omarmipi]

I just bought a pair of the Peerless 831882 Exclusive woofers to make some small book shelve speakers with. Does anyone have project plans for these woofers with a nice tweeter? I figured I'd try to ask before I contract Madisound to create some custom crossovers.

[Jonasz]

Here's one: http://home.wanadoo.nl/dezaire/golden/golden.htm

[omarmipi]

Here's one: http://home.wanadoo.nl/dezaire/golden/golden.htm

Thanks but for some reason I am unable to view the plans. And unfortunately I cannot read the language on that site.

[ThomasW]

The plans are links (aka thumbnails)

[Hdale85]

Hmm was just about to do that....

[omarmipi]

Awesome!!! Thank you very much for posting that. For some reason the link wasn't working for me the 1st couple of times but now is.

[peter_m]

unfortunately I cannot read the language on that site.

Just go to:http://www.google.com/translate_t

and you get this: http://www.google.com/translate?u=ht...&hl=en&ie=UTF8

[John D]

I know the designer. He knows how to design speakers. I've heard a couple of his designs and they are all very good.
I could translate some parts for you (from Dutch to English, in case you didn't know ), if necessary.

[bobhowell]

I got a pair of Peerless 831882's recently and am wondering it anyone has built the design shown here and cares to comment.

Bob Howell

[bobhowell]

Anybody built any speaker with this woofer and care to comment?

I have two and am planning to start soon on something.

[davey_m]

The port output at 800Hz is almost as high as the primary port output between 50 and 90Hz. Presumably the driver's rear radiation couples too efficiently to the slot port resonance and contributes to some 2 - 3 dB excess output at 800Hz as seen on the ATB Precision plot.

Perhaps try a cylindrical port mounted high eg behind the tweeter.

[bobhowell]

The port output at 800Hz is almost as high as the primary port output between 50 and 90Hz. Presumably the driver's rear radiation couples too efficiently to the slot port resonance and contributes to some 2 - 3 dB excess output at 800Hz as seen on the ATB Precision plot.

Perhaps try a cylindrical port mounted high eg behind the tweeter.

??? Don't follow!

[5th element]

??? Don't follow!

Look at the low frequency response plots of the woofer on the link posted at the top of the page.

You see the usual woofer roll off, with the port contribution slightly below it. However the port also appears to have high output around 800hz.

Whether or not this has been commented on in the design I don't know.

[fjhuerta]

??? Don't follow!

I think he means that port resonances at 800 Hz are almost as loud as the port's output at its tuning frequency...

[Dave Bullet]

Looks like the design favours nearfield (eg. computer / desk) listening or for close wall mounting. Does not look like enough baffle step compensation applied - loose translation, the speaker will sound "thin" and bass-less if you use it in a conventional (on stands in the room away from the rear wall) manner.

[davey_m]

Yes it appears there's no BSC. It is clearly visible in the ATB Precision plot, which is anechoic.

[bobhowell]

I got it. I am planning to run it sealed with sub. But I will have to think about BSC. I think I will want that. He has comments about the design but Google Thanslate conceals the meaning. Hence my caution. Seems he recomends/offers version to cut output abound 4000hz. I don't know if there is more.

In 7 L, roll off is gradual and I could xo to sub at 80-120 as needed.

Thanks for the help

Bob

[Dave Bullet]

I got it. I am planning to run it sealed with sub. But I will have to think about BSC. I think I will want that. He has comments about the design but Google Thanslate conceals the meaning. Hence my caution. Seems he recomends/offers version to cut output abound 4000hz. I don't know if there is more.

In 7 L, roll off is gradual and I could xo to sub at 80-120 as needed.

Thanks for the help

Bob

A sub won't compensate for a lack of baffle step compensation. See in the overal frequency response of the system there is a gentle rise in response from 100Hz to about 700Hz of about 3 - 4 dB? This is the baffle step phenomenon. The sub will round out things - say to 120Hz max. You'll still have a bright / forward sounding speaker.

Without changing the crossover, all you can do is place the speakers hard against the wall and block the port / build as a sealed design.

[bobhowell]

Looks like the design favours nearfield (eg. computer / desk) listening or for close wall mounting. Does not look like enough baffle step compensation applied - loose translation, the speaker will sound "thin" and bass-less if you use it in a conventional (on stands in the room away from the rear wall) manner.

I have studied this design and have questions about the graphs. Looking at the 2nd graph, which is the corrected one, the spl rises from 1000hz down to about 150hz. Then it falls off at about 100hz, quickly. This seems to be too much BSC as I read it. Everyone else says not enough. So how am I miss reading this?

Clairify please,

Bob

[davey_m]

That second graph comes from a nearfield measurement and would not show the baffle step. The ATB precision graph at the end is anechoic and shows the baffle step.

[Dave Bullet]

As davey_m said. A nearfield measurement (one where the microphone is placed close enough to the driver that the baffle effect is swamped by the driver's "natural" response) is only useful for low frequency response measurements, or where you do NOT want the effect of the baffle to factor.

The other tipoff is the low value series inductor for the woofer. Unless the driver has baffle step "designed" into it (most don't) then the inductor is usually around 2mH (or greater) to indicate some level of baffle step compensation. The other option is a lower value inductor, but a parallel resistor to "shave" a few dB off above where the inductor resistance exceeds the parallel resistor. The one in the design above is only 0.68mH

[bobhowell]

Thanks. Now I see. One thought is to put it in a sealed, 3-4L box, which gives a Q of .700 or so, and power handling of about 30 watts. My subs are one of the NHT buyout amps with a spectrial tilt, driving two, 10"woofers in seperate cabinets spaced 8" apart and another sub available to help, if needed, to even out room modes. Can I use these adjustments to level out the responce? I will be experimenting with REW.

Thanks for the help,

Bob