Scott,
I have 8PR155 and 8PR200 in stock and I can check. you want to know about 8PR155 dust cap? it's not vented. I'll check and post some pictures in details.
Thanks for posting this. Is the statement drawn from actual experience with this driver and the 8pe21? If so, could you please elaborate on the setup and the differences you experienced?
Valuable info!!
Maybe the unit(s) have a vented pole piece, in which case it could easily be a design choice to have a solid dust cap, for the forced air effect (?)
It's more known as a very good mid bass horn driver, so maybe people think it can not be good as a direct radiator. Well it is
The way I'm reading posts, people aren't hating it. Not saying it's bad. Some are saying they liked the Audax and the Faital Pro better. That's all. I have no personal experience with any of them so gathering information and opinions.
Did you prefer it to other mids?
Cheers
I checked it and it actually has a vented magnet. check this out:
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
From the datasheets, the aluminum shorting ring on the Faital 8PR155 does reduce the high frequency impedance rise better than the B&C 8PE21 curves.
From the $150 Faital 8PR155 datasheet SPL measurements, the 45-degree curve appears to have the proper beaming around 2,000Hz to blend well with the +/- 40_degree horizontal TPL 150 horn.
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What directivity curve do you favor? With the 8PR155 the directivity function will quickly increase from 80-degrees at 2kHz to the 180-degree baffle around 1kHz.
With a horn loaded midrange like the 8" JBL CMCD-82 in the PT-K95MH waveguide (90° x 50°, 18 x 18in) you would have ~90° x 50° pattern control down to ~300Hz.
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So, do you continue building midrange horns for efficiency and pattern control?
From the $150 Faital 8PR155 datasheet SPL measurements, the 45-degree curve appears to have the proper beaming around 2,000Hz to blend well with the +/- 40_degree horizontal TPL 150 horn.
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What directivity curve do you favor? With the 8PR155 the directivity function will quickly increase from 80-degrees at 2kHz to the 180-degree baffle around 1kHz.
With a horn loaded midrange like the 8" JBL CMCD-82 in the PT-K95MH waveguide (90° x 50°, 18 x 18in) you would have ~90° x 50° pattern control down to ~300Hz.
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So, do you continue building midrange horns for efficiency and pattern control?
I am waiting for my budget to let me begin my build. I WILL be building a 3way design with the TPL150, 3451 and Beyma SM110N pair. Its what I have but still have to order the TPL's, I have everything else. Things have been very slow for me and coming up with a budget. Four children makes progress on most things very slow. BUT I will build it before this year is over.
Also might try to buy the 18 Sound 10" mentioned earlier for a center channel.
I still have to build it. I wanted bigger bass drivers but this is all I could afford. PLUS if I wanted, the 10" bass drivers can be used full range quite well also. I looked at dual 15's for my bass wants for each speaker but cant fit wide towers in my space. Can just squeeze in 12" wide towers so the 10's will have to do.
I wanted bigger bass drivers but this is all I could afford. PLUS if I wanted, the 10" bass drivers can be used full range quite well also. I looked at dual 15's for my bass wants for each speaker but cant fit wide towers in my space. Can just squeeze in 12" wide towers so the 10's will have to do.Thanks for the pictures.
Can someone please educate me on the implications of the vented magnet? Good/bad, for what, why?
one of main reasons is ventilation. poor ventilation results in hotter coil. hotter conductor has higher resistance not mentioning the risk of voice coil damage
Thank you. I see. I imagine the ventilation is critical if it's going to be used at 200W (its AES power handling). But for a 97dB sensitivity driver in a home setting...probably not going to take a whole lot of power...maybe 2W peak? I thought the ventilation would have added benefits.
Thanks again for the learning!
Nope. It's as likely to be a drawback as anything for a driver this efficient used at home levels, the venting can sometimes contribute a resonance, that said, one could stuff the vent with a breathable foam to suppress any issues.
The power handling is a good thing (bigger coils will heat up less particularly dynamically), but air cooling is a long-term matter run at meaningful power levels, which 97dB mids used at home are not.
exactly. that's why an under-hung 15" woofer with 100-150watts is better than a same woofer with a long coil with 500-600watts handling power. under-hung coils are shorter thus stay in the effective area of magnetic field within their linear excursion and you still can have about 120db spl with that 150 watts on them and have no worry for coil damage