More Midrange Sweet Spot

[Pano]

The PRV Audio D270Ph-S I would call a midrange horn driver. I haven't heard it, but have used other phenolic drivers with good results.

As for me, I just use a multi-cell horn when a wide midrage is needed. Always works, but it's not the simplest solution.

 

[grayxxx]

The PRV Audio D270Ph-S I would call a midrange horn driver. I haven't heard it, but have used other phenolic drivers with good results.

As for me, I just use a multi-cell horn when a wide midrage is needed. Always works, but it's not the simplest solution.

Thanks Pano.......After seeing some phenolic reviews being the B&C DE250
suppose to be quite good, above average....and the D270 review out it as the same and the 290.So going to have to decide on those..
https://www.ebay.com/itm/B-C-DE250-...505947&hash=item3394d05b39:g:sH0AAOSwVFlUBzo2

 

[grayxxx]

Thanks Pano.......After seeing some phenolic reviews being the B&C DE250
suppose to be quite good, above average....and the D270 review out it as the same and the 290.So going to have to decide on those..

Originally Posted by PanoThe PRV Audio D270Ph-S I would call a midrange horn driver. I haven't heard it, but have used other phenolic drivers with good results.

As for me, I just use a multi-cell horn when a wide midrage is needed. Always works, but it's not the simplest solution.

Pano......... And then the mid driver that launched a thousand ships....
PVR
Throat Diameter: 2"
Type: Bolt-on
Nominal Impedance: 8?
Rated Power Handling: 200 Watts
Program Power: 400 Watts
Sensitivity (1W/1m): 109 dB
Frequency Range at -10 dB: 600 - 7,000 Hz
Recommended Hi Pass X-Over: 700 Hz
Voice Coil Diameter: 4"
Magnet Material: Ferrite
Diaphragm Type: Phenolic
Weight: 21.5 Lbs

 

[plasnu]

grayxxx, I think this kind of 15"+10" combination was started by JBL in 70's (JBL 4343 4 way etc). While this combination obviously gained popularity and it has been proved, but I don't still know why they chose 10" instead of smaller unit.

 

[chris661]

Well, a bigger cone will show lower distortion (from greater efficiency and reduced excursion), greater power handling, and a narrower beamwidth towards the crossover point.

It's likely that the JBL engineers wanted at least one of those.

Chris

 

[grayxxx]

grayxxx, I think this kind of 15"+10" combination was started by JBL in 70's (JBL 4343 4 way etc). While this combination obviously gained popularity and it has been proved, but I don't still know why they chose 10" instead of smaller unit.

Plasnu...dude...I have been thinking about the 10" vs 6.5s or 8"s....with poss
horn not sure now....The cabinet makes changing out post 1 picture....Things have changed on mid speakers and like Chris661 4" plat form shoes he wears to disco
night....C19 style.....

 

[grayxxx]

The JBL 4345 18" woofer 10" mid, lens,super tweet....

Quote:

No, I don't have anything to sell or any other dog in the hunt. But I've been around long enough to see a whole lot of ambitious 4 way projects fall by the wayside due to more ambition than know how. I've seen guys build 4345 clones - with the correct drivers - and still ripping their hair out due to the complexity of the beasts. I know just enough about it to know I'd have a better chance of flying to the moon than building a 4 way crossover that actually works.


I think this answered my question


Quote:
There is a thread on that here if you go decide to go that route ...
nearly 10 years back I bought a pair of used 4341 (the early end of the big 4 way designs, with 15s instead of 18" woofers)
My 4341s came with a pair of 2123s as the mid bass drivers - the original owners swapped in whatever was handy when their 2121s failed (probably the typical crumbling surround issue) . I tried to be a purist and sold off the 2123s and had one of the JBL coners build me a pair of 2122s - which was doable 8 years ago when I was headed that path. Seemed like a good solution at the time.
I'm not sure how available the 2122 parts are now.

*********************NEW
What a lot of the more modern builders of 4345 clones do is build a 3 way crossover to handle the 10" mid-bass driver, mid-horn and the super tweeter,
then use an external active crossover at 290Hz and biamp the 18 woofer and the upper 3 drivers.
I followed that guidance when I had a 4341 system a few years back.
BMWCCA uses an Ashly XR1001 crossover and Crown amps on his system.
Easier than trying to find the tapped inductor and switch JBL used in the original design, and better performance overall.

Start here for Crossover notes -
4345 4355 networks

or compare differences in this launch page for the whole 434x series!
Technical Ref Threads for 434x monitors

 

[GM]

.......I don't still know why they chose 10" instead of smaller unit.

FWIW, in post 15 I show a technically good reason why since I learned it from reverse engineering some W.E./Lansing/Altec driver designs.

GM

 

[grayxxx]

FWIW, in post 15 I show a technically good reason why since I learned it from reverse engineering some W.E./Lansing/Altec driver designs.

GM

GM ...dude....Every time I read one of your tech items I think about running
away from home.......to live behind "Dairy Queen"...Im picking on you...
You are correct-o....

thanks.....

 

[Pano]

For years I ran a PA that used a front horn loaded 10" midrange. Horn tweeter above, woofers below. Worked well enough. A wide midrange sweet spot was not the goal, but it did have good coverage.

A PA from GM's neck of the woods. OAP.

 

[grayxxx]

For years I ran a PA that used a front horn loaded 10" midrange. Horn tweeter above, woofers below. Worked well enough. A wide midrange sweet spot was not the goal, but it did have good coverage.

A PA from GM's neck of the woods. OAP.

PANO.....If you gang up with GM....Im going to do it .....Im thinking about running away from home.......to live behind "Dairy Queen"..or join the circus.and take my computer 2" X 8 speaker array with 1/4" x 1/2" ports running a 3 watt power amp at .00000001 amp load...you will be sorry ....if you come for ice cream or to barrow the array....for a conference call small array PA job...


My sweet spot mid back ground mid presents with the mid horn or by speaker
with pot. was in stereo use, but that may applied for PA..You dont think 10"
midrange with a mid horn adjusted in the back ground of the speaker mids would not give a depth of field of the mid sound.. vs. both mids at same volume.

 

[Pano]

You would likely end up with much comb filtering and lobing. How much depends on many things, like driver offset, volume, horn profile, etc. It's not something I want to try, but who knows, you might like it!