Lets see your O.B. speakers....!


Poultrygeist

Re: Lets see your O.B. speakers....!
« Reply #621 on: 18 Jan 2025, 01:35 pm »
Interesting sliders. One issue I have is maintaining a decent back tilt to the baffles so the F-15's fire toward my ears. Some of the barrel shaped baffles ( incorrectly called Betsy's ) seem too low to the ground to get much of a tilt.

opnly bafld

Re: Lets see your O.B. speakers....!
« Reply #622 on: 18 Jan 2025, 08:13 pm »
Turn that frown upside down.  :wink:




opnly bafld

Re: Lets see your O.B. speakers....!
« Reply #623 on: 18 Jan 2025, 08:16 pm »
Then you need a tweeter because 15" wideband off axis....





FullRangeMan

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Re: Lets see your O.B. speakers....!
« Reply #624 on: 19 Jan 2025, 03:58 am »
Turn that frown upside down.  :wink:
Nice experiment. How sound the soundstage this way ?

Poultrygeist

Re: Lets see your O.B. speakers....!
« Reply #625 on: 19 Jan 2025, 11:40 am »
Can't have much of a back wave.

opnly bafld

Re: Lets see your O.B. speakers....!
« Reply #626 on: 19 Jan 2025, 12:34 pm »
Nice experiment. How sound the soundstage this way ?

I couldn't say, didn't bother to listen to them at Decfest last October.

There is a long thread about them (I haven't read it), maybe a way to put the speakers against the wall instead of out in the room??? As PG mentioned above, not much of a backwave.

gils

  • Jr. Member
  • Posts: 81
Re: Lets see your O.B. speakers....!
« Reply #627 on: 31 Oct 2025, 02:28 am »
hello,

This sub H-Frame

Rainy weather, back to indoor tinkering! :D

I had an Infraflex 90x90 cabinet taking up space, and I have two 18-inch JBL 2279H drivers (short voice coil). A bit of experimental tinkering, and all in all, the sound is quite pleasant.

The subwoofer is clean and fairly precise despite a rather complex modal response. It goes quite low, it handles the power well, so why not use it? :P

T&S drivers used.
SD  1290
RE  5.6
BL  22.45
VAS  363 L
QES  0.38
QMS  5.05
QTS  0.35
MMD  150 g
MMS  177 g
Xmax  8 mm (évalué sur la base du 2278 H)
Pmax  800 W
Fs  30.61 Hz

The circuit uses an analog active crossover and a 150W Class B stereo amplifier (one channel per speaker).

It's basic, but it's an estimate.





Quelques mesures faite à 1 m dont une à 100 db/2.7 V



decay sur 320 ms








mesure HPs séparés courbe verte et rouge puis les deux combinés courbe bleu



And video

https://youtu.be/PltrMse7luI


cordialy.


Poultrygeist

Re: Lets see your O.B. speakers....!
« Reply #628 on: 9 Nov 2025, 09:46 am »
I recently added a single Lii Audio W-15 to augment the bass and couldn't be happier with the results. The W-15 is so heavy it requires its own baffle as well as wheels to move it around.




Poultrygeist

Re: Lets see your O.B. speakers....!
« Reply #629 on: 9 Nov 2025, 10:03 am »



Poultrygeist

Re: Lets see your O.B. speakers....!
« Reply #630 on: 9 Nov 2025, 10:10 am »



pompon

  • Jr. Member
  • Posts: 33
Re: Lets see your O.B. speakers....!
« Reply #631 on: 1 Feb 2026, 02:29 am »
Here my OB!

FaitalPro 18fh500 as woofer (45-250hz)
Supravox 215rtf64 as mid (250-2800hz)
Raal 140-15d for highs (2800hz+)
Rel G1 for under 45hz


opnly bafld

Re: Lets see your O.B. speakers....!
« Reply #632 on: 1 Feb 2026, 07:41 pm »
Here my OB!

FaitalPro 18fh500 as woofer (45-250hz)
Supravox 215rtf64 as mid (250-2800hz)
Raal 140-15d for highs (2800hz+)
Rel G1 for under 45hz



Nice (low budget  :wink: ) build.

opnly bafld

Re: Lets see your O.B. speakers....!
« Reply #633 on: 1 Feb 2026, 07:44 pm »
Waiting for it to warm up a little so I can make baffles for a pair of Zenith 49CZ903 drivers.




opnly bafld

Re: Lets see your O.B. speakers....!
« Reply #634 on: 13 Feb 2026, 04:43 pm »
4' x 2' x 3/4" birch plywood baffles - mounting holes cut yesterday evening - no bracing yet - no legs/support - held up by an ottoman (L) and a DR table chair (R) so I can listen/evaluate.
So far I am impressed with the bass from these Zenith 49CZ903's (FS is @ 52Hz - some 30+ Hz lower than the popular 852's) with the music I mostly listen to (Brubeck, Petersen, Webster, etc, Mozart, Paganini, etc).
I was listening to a Focal demo disc at louder SPL's than I realized (louder than I normally listen) when a choral piece (Verdi track #14) made these drivers fall apart*, everything before it was pretty good, and the choral piece was much better after lowering the volume control some.
If you like complex music fairly loud these are not for you. Hopefully you already knew that.





* part of the problem may have been the 1~2 watt inexpensive triode strapped JBH 6P14P tube amplifier I was using was past its limit.
* Edit: A 7 watt SET did much better playing the track mentioned above.
« Last Edit: 8 Mar 2026, 10:16 pm by opnly bafld »

opnly bafld

Re: Lets see your O.B. speakers....!
« Reply #635 on: 8 Mar 2026, 10:13 pm »
A pair of Jensen P15RJ alnico drivers have joined the fun.




Jon L

Re: Lets see your O.B. speakers....!
« Reply #636 on: 9 Mar 2026, 06:03 pm »
My Zenith 49CZ852 are basically sitting on similar area of similar baffle, and I do have 15" woofers in house but have been hesitant to add the woofers to same baffle due to the worry the woofer vibrations will detract from the famous midrange purity. 

How do you have the two drivers crossed over and any diminishment of midrange qualities? 

opnly bafld

Re: Lets see your O.B. speakers....!
« Reply #637 on: 10 Mar 2026, 01:48 pm »
The Jensen's are excellent also and play fairly high, enough so that I was listening to them just sitting on the floor when I first got them and started thinking about using them separately with a tweeter.
I just cut the baffles late Sunday afternoon (writing this early Tuesday morning) and added the 15's so I need more free time to evaluate, but will likely just use a coil and another amplifier for the Jensen's.
The Zenith's will be used connected directly to the amplifier. Lots of bracing and legs/feet and finish yet to be done. Listening at what most I know call loud is not something I do, never did even when young.

 :nono: I was eager to listen Sunday evening and because I was curious what the paralleled DRC would be I just hooked them up paralleled/no filter (something I would normally smh at  :duh: ) and also they have the same sensitivity. They actually sound pretty good fullrange together and when I put my head by the baffle between the drivers the treble sounds like it's coming from the Zenith. Unfortunately using them in parallel with a coil on the Jensen will likely lower it's sensitivity too much (-2 dBs?) to be effective and will require bi-amping. Surprisingly siting here listening and posting it sounds like the Zenith are playing alone with a little bass boost added.

The Jensen (advertised as 5.7 DCR by seller - actually 4  :( ) and the Zenith in parallel are a nominal load of @3 ohms, my tube amplifier isn't concerned.
« Last Edit: 11 Mar 2026, 02:54 pm by opnly bafld »

FullRangeMan

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Re: Lets see your O.B. speakers....!
« Reply #638 on: 10 Mar 2026, 04:49 pm »
The P15 no bell had a 16Ω option with slight lower bass response.
Seems a great Full Range with the wonderful Alnico 5.
https://www.jensentone.com/vintage-alnico/p15n-no-bell
P15N-NB
15",
50 watts
Available in 8Ω, 16Ω
One of the first speakers ever used in a guitar amplifier, the P15N was loaded in the earliest Fender Bassman® and Bandmaster® amps, setting the milestone for those classic tones. The P15N delivers a warm, full bodied tone, with deep basses, and a nice, extended top end. Excellent for all different shades of clean and pushed clean tones.

opnly bafld

Re: Lets see your O.B. speakers....!
« Reply #639 on: 10 Mar 2026, 06:00 pm »
Mine are R with J, meaning special design, they came out of a Magnavox console (many had 4 ohm loads and OPTs to match).
'61 date code, Alnico - P first letter, ~6 ohms, Fs ~60 Hz, ~95 dB sensitivity
What little info I could find on P15R and RJ they are great drivers for open back and OB 2 ways.

« Last Edit: 10 Mar 2026, 09:36 pm by opnly bafld »