Out of the 4350B data sheet the enclosure volumes are:Originally posted by Giskard
From PSS AUDIO's post, the six 4350 ports would tune that volume to roughly 26 Hz, and the spec sheet states 25 Hz.
Given the dimensions of the Westlake ports, I get roughly 22 Hz for a 9 cubic foot volume and roughly 19 Hz for a 12 cubic foot volume. I think it's safe to bet they're tuned to ~ 20 Hz
Low Frequency: 9.5 cubic foot
High Frequency: 1.6 cibic foot
Once again if this can help...
"Out of the 4350B data sheet the enclosure volumes are:
Low Frequency: 9.5 cubic foot"
...so how do they get two 2235s in a 9.5 cu. ft. cabinet and tune it properly when JBL suggests an 8 cu.ft. cabinet for a single 2235?
Tom
Well I guess that 2 x 8=9.5!Originally posted by Tom Loizeaux
[B...so how do they get two 2235s in a 9.5 cu. ft. cabinet and tune it properly when JBL suggests an 8 cu.ft. cabinet for a single 2235?
Tom [/B]
As tea for two and you for me ....
In fact they made a typo error I presume. The overall size of the 4350 is .89m x 1.21m x .51m = 549 liters.
The internal size is in fact .8m x 1.17m x .42m = 437 litres, less 45 litres for the 2202H and perhaps 10 litres more for the horn, driver, 2405 and xover.
There is in fact 390/400 litres for two 2231H, i.e. 14 cu.ft for both drivers.
In such a case we are quite close to the 16 cu. ft requested!
I personally do not use the 2235H as I am just listening my 4350…Originally posted by Giskard
Tom? Yuri? You guys are running 2235H's in 8.0 cubic foot enclosures?
... the 4350 but the six ports/ducts as specified by Yuri support an Fb = 26 Hz in a volume of 9.5 cubic feet. Of course, actually physically measuring the Fb of a 4350 and a 4355 will put the speculation to rest
If you made the calculation out the 6 ports for a 9.5 cu. ft.; what will it be with a volume of 390 litres?
~ 22 Hz
In such a case one can say that a 4350/55 is tuned at 22 Hz, quite close to the Westlake ...Originally posted by Giskard
~ 22 Hz
Once again, what can eat, with or without, the bones a 4350/55?
That is the question, to be or not to … JBL 4350/55!
At this point I would prefer to see the actual Fb measurements.
I get bored with speculation after awhile
"The 4345's where tuned lower than these. Those 2245's are fantastic. I don't believe these 2235's will ever sound as good as they did on extreme lows. "
Hey, Ken...
That 5234A crossover has DIP switches that enable adjusting the hi-pass filter (sub 40Hz). There is a setting for +6dB boost at 20, 30 and 40Hz (as well as others). Do you recall whether you had that hi-pass filter set for anything other than "factory" (flat)? If so, you might be making a "biased" comparison
And if so, there may be a similar setting on that Westlake crossover to provide the slope you're accustomed to.
Just a thought...
bo
"Indeed, not!!"
[QUOTE]Originally posted by boputnam
[B]"The 4345's where tuned lower than these. Those 2245's are fantastic. I don't believe these 2235's will ever sound as good as they did on extreme lows. "
Hey, Ken...
That 5234A crossover has DIP switches that enable adjusting the hi-pass filter (sub 40Hz). There is a setting for +6dB boost at 20, 30 and 40Hz (as well as others). Do you recall whether you had that hi-pass filter set for anything other than "factory" (flat)? If so, you might be making a "biased" comparison
Good point Bo.
I sent that 5234a away to have the cards custom made and installed. I never took the top off to see what he set them at. I suspect they are set flat. There was no need to check as I was very happy with the bass response.
That's just complete bunk that dual 2235H's would fall short...
There is no way in hell a single properly loaded and tuned 2245H is going to spank dual properly loaded and tuned 2235H's in the VLF.
**************************************************
edited by Giskard on 07-03-2003 at 03:17 PM
Here's the measured response of the stock 4345 and the stock 4355:
4345
2245H in 9.0 cubic feet tuned to 32 Hz
(impedance curve trough at ~ 26 Hz, passive filter)
March 9th, 1981
4W @ 2m
half-space (2 Pi)
95 dB, 4W, 2m
-3 dB at 36 Hz
-6 dB at 32 Hz
-10 dB at 26 Hz
4355
two 2235H in 9.5 cubic feet tuned to 32 Hz
(impedance curve trough at ~ 28 Hz, active filter)
April 30th, 1981
4W @ 2m
half-space (2 Pi)
96 dB, 4W, 2m
-3 dB at 34 Hz
-6 dB at 28 Hz
-10 dB at 24 Hz
Last edited by 4313B; 07-03-2003 at 12:17 PM.
After seeing all the above I have no doubt Giskard is correct. The problem is a combination of improper setup, low damping factor (200) on the Hafler 500's.Originally posted by Giskard
That's just complete bunk that dual 2235H's would fall short...
There is no way in hell a single properly loaded and tuned 2245H is going to spank dual properly loaded and tuned 2235H's in the VLF.
First, as time permits they need to be setup properly. Second, I and others believe these require a more advanced amplification system. Westlake did warn me of this. These issues will be addressed as time and $$$ permit. Once these are done I am sure the vlf will trip the earthquake recording equipment throughout southern California.
In retrospect, I wish I had not mentioned it until these were setup properly. I just wanted to share my excitement and initial impressions with the only people who can understand this madness.
Ken
Understood
Imagine our vexation at not being able to be there with you to experience first hand
GiskardOriginally posted by Giskard
Understood
Imagine our vexation at not being able to be there with you to experience first hand
The spare room has clean sheets. When can you be here?
Would love your expertise in setting these up.
Ken
BTW Ken, whith regards the ground loop hum, have you tried plugging the amp(s) into another circuit from the rest of the equipment. I know from experience that really strange things can happen with hum - something only those with high sesitivity speakers really know about - and sometimes you have to try every possibility. I myself have to run my bass amp (citation 19) on a different circuit from everything else, including the dedicated line, to avoid hum...go figure !!
Bernard
What you are noticing now will pry end up being better in the long run. those pry sound less thick on the lows which is better. get a Fast High current power amp and trust me the lows will no longer be and issue. $$ Good Luck. Im out of money. In 30 years at this Ive owned about 40 power amps all large 250 and above a side. You know what might be intresting to try on those would be ADCOM 555II for the lows. its lean controlled and dam powerful amp. ive had that amp put mono blocks to shame on lowed control and heck its only around 300. Also the 565 monos Ive had side to side with a 7000.00$ power amp and the lows were very close into 8 ohms.
Von Schweikert VR-8
Canary Ref. 1 300B monoblocks. 300Bx16
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