Purrsay - Silverline

[Sigil]

Just finished the bracing on 2 LCR's I decided to keep the center the same. Maybe with an optional baffel and top mounted tweeter for use as a horizontal. I have to cut all the supports for the last LCR. Whenever. No veneer or final touches until I get the working crossover. Next in line. Alll the rest can be done indoors now. Lots of time before the holidays this Winter. The drivers I have left will be used as surrounds. 2, 6.5" 8ohm HDS, 4, 4.5" PPB Peerless 4ohm. I would have to find 4, 4ohm silk dome tweets. Dayton does have them. Better order soon!! There goes my full driver stash!!

[thekorvers]

I've used that Peerless buyout woofer a couple of times. Really great sounding woofer with excellent sensitivity. It could easily match up to the silky in an MTM without a midrange driver. Its only short coming is that it won't extend very low in frequency. LouC used it in about 22 Liters in his Lecbos project with a F3 of about 70 Hz. I recently used it in an MTM in 17 liters with about the same F3. I matched it up with the Dayton Audio ND25FW tweeter. Awesome sounding speakers for very little money. I'd publish my design but the woofer is no long available :( wish I could buy 100 more of them...

Always a good idea to publish a design. There are plenty of those floating around or sitting on shelves somewhere. I think I may even have a pair somewhere. Just basic information of size, driver location, tuning etc. is enough for most people.

[thekorvers]

I've used that Peerless buyout woofer a couple of times. Really great sounding woofer with excellent sensitivity. It could easily match up to the silky in an MTM without a midrange driver. Its only short coming is that it won't extend very low in frequency. LouC used it in about 22 Liters in his Lecbos project with a F3 of about 70 Hz. I recently used it in an MTM in 17 liters with about the same F3. I matched it up with the Dayton Audio ND25FW tweeter. Awesome sounding speakers for very little money. I'd publish my design but the woofer is no long available :( wish I could buy 100 more of them...

By the way, I calculated the efficiency of the woofer to be somewhere around 90.6 dB, higher than PE's specs. I think a silky will be just able to match up in an MT or MTM.

In a 17 liter net enclosure, tuned to 57 Hz, I see an f3 of 54 Hz. This is in an alignment using parameters which are an average of 4 tested units.

Where does your f3 of 70 Hz come from? Is this calculated or tested? What parameters did you use?

[Sigil]

70 hz?
I think that was a quesstimate??
I was hoping for some low frequency extension by my eq.. I be happy with 80 hz :/
I've heard them briefly on another crossover, sounded ok..

[Sigil]

By the way, I calculated the efficiency of the woofer to be somewhere around 90.6 dB, higher than PE's specs. I think a silky will be just able to match up in an MT or MTM.

In a 17 liter net enclosure, tuned to 57 Hz, I see an f3 of 54 Hz. This is in an alignment using parameters which are an average of 4 tested units.

Where does your f3 of 70 Hz come from? Is this calculated or tested? What parameters did you use?

I'm was positive that I seen that they were 90.5 db.
I checked back and it was 89.5!!
I had a few 2 ways. I wanted a 3 way. I can always pop in other drivers down the road. Hopefully not!

[PWR RYD]

By the way, I calculated the efficiency of the woofer to be somewhere around 90.6 dB, higher than PE's specs. I think a silky will be just able to match up in an MT or MTM.

In a 17 liter net enclosure, tuned to 57 Hz, I see an f3 of 54 Hz. This is in an alignment using parameters which are an average of 4 tested units.

Where does your f3 of 70 Hz come from? Is this calculated or tested? What parameters did you use?

Calculated F3 of 68 Hz from Unibox using the average of my four measured woofers. I'll have to search a bit to find those T/S's. If I remember correctly the box model didn't change much using the PE published parameters. I have enough subwoofers available that a low F3 isn't a design concern.

[PWR RYD]

I believe my calculated sensitivity with the two woofers in series was about 90.5 dB/2.83v/m

[Sigil]

Changed name to Phantom Edge!!
In the process of sealing the MDF.
Maybe a start to a passive cross on the weekend.

[Sigil]

Had time again! Left and Right are mdf sealed, ready for vinyl wrap and baffel sealing tape. I initially used Rust-Oleum for the first to seal it. Found it was way cheaper to use water and wood glue for the other two! Practice for paint, if I ever do.. The edges are routed for aluminum corner edging. Had a chance to start a crossover in WinPCD Like someone mentioned, I will be padding down the mid substantially. Too bad I can't use the mid to bump the lower frequency without upsetting the impedance load. Non the less I will see what I can come up with soon. At least the mid is down at 86db in the low freq. end slowly rising. Getting close to the holiday season. See if I can get it done. The 3rd channel is still in pieces eating to go through the same process. B way quicker.

[Sigil]

Had a few mins. Went with a 2nd order Linkwitz Riley. I will have to think about it later. It looks good on paper!! :/

[thekorvers]

By the way, I calculated the efficiency of the woofer to be somewhere around 90.6 dB, higher than PE's specs. I think a silky will be just able to match up in an MT or MTM.

In a 17 liter net enclosure, tuned to 57 Hz, I see an f3 of 54 Hz. This is in an alignment using parameters which are an average of 4 tested units.

Where does your f3 of 70 Hz come from? Is this calculated or tested? What parameters did you use?

I had not looked at this thread for a while. I had done this alignment a number of years go and initially got it off my old erratic computer, not realizing that I was comparing apples to oranges in that my model was for one driver while your design calls for two. So you are right and I need to clarify my statement:

In a 17 liter net enclosure, for one driver, tuning to 57 Hz I see an f3 of 54 Hz and for two drivers, tuning to 60 Hz I see an f3 of approximately 70Hz.

Like Craig says, if you are using a sub, I see no problem. Personally, without a sub, I think I would build this a little larger to get the lower f3. A moot point now.

[scottvalentin]

It does look really good on paper - don't forget to add the DCR to your inductors though, that resistance will affect the response.

[Sigil]

Ya, was fairly busy. Its been awhile.
I was suppose to be done by Christmas!!
Well, L/R's are ready for a crossover.
I will probably order the parts soon.
I was wondering how the air coils perform over iron cores, in the woofer section considering the price difference. Worth it?
I can see with my first design that I could have mounted the tweeter on top of the cabinet and the mid right below the tweeter on the baffle. Ok for now!
A couple little quirks already have new designs on my mind!! :/

[Sigil]

It does look really good on paper - don't forget to add the DCR to your inductors though, that resistance will affect the response.

It does look really good on paper - don't forget to add the DCR to your inductors though, that resistance will affect the response.

What do you mean, about DCR? Scott.
Look for low DCR?
I had an idea about air coils, although wasn't sure till I just looked it up. Low DCR has improved dynamics over iron core. It doesn't change my other parts though because of the DCR. I hope!! Pray lol

[scottvalentin]

If you look at any of the iron core or air coil pages on the PE website, it will show the DCR value (just an added resistance to the crossover circuit). Where you see a coil in your circuit diagrams above your coil values, just add the DCR of the parts into that section. It will have a small affect on the response, but better to have it in and see what it does in simulation than to hope it doesn't affect things too much.

Iron core is good for the higher Inductor values (because they are cheaper! - that's my opinion only!) and air coils good for the other values (say below 2 mH). Others may chime in if there are specific benefits or drawbacks between the two types.