PDA

View Full Version : Can 250TI BQ crossovers be used on 250TI's?



Ezel
05-11-2003, 04:51 PM
Hi all..

I wonder if the crossover of JBL 250TI BQ could be used on 250TI's.. I own a pair of 250TI's with older crossovers Recently I find on e-bay (german E-bay) new produced crossovers for 250TI BQ's (The ones with never designs and biwire possibility)..

After checking the two model of 250TI's I found out the major difference of Titanium tweeters Older models (250TI) uses 044TI while new Jubilee models (250TI BQ) uses 035TIA-1.

These are not the only differences. 250TI has an impedence of 8 ohms with a frequence range of 30-27kHZ and sensitivity of 90dB. 250TIBQ (Newer Jubilee model) has an impedence of 6 ohms with a frequence range of 30-25kHZ and sensitivity of 89dB.

The crossover frequencies at 250TI are 400Hz., 1.4kHz, 5.2 kHZ while they are 350Hz., 1.2kHz, 5.5 kHZ at 250TI BQ.

The other drivers (LE14H-1, 108H, 104H) are the same.

Is there any possibility to upgrade older 250TI's with the crossovers of the new ones?

Thanks

Ezel

4313B
05-11-2003, 05:07 PM
From inspection it looks like it could work. If you can give me a few days I can run some impedance curves on the 044Ti to make sure from an electrical standpoint. The 035TiA has a very sweet impedance curve, I don't recall the 044Ti having such a nice curve but I could be wrong. I saw those networks on the German eBay but didn't happen to look at the time limit on them.

Ezel
05-11-2003, 05:13 PM
Here are two ongoing auctions:

http://cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&item=3324918891&category=21997

http://cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&item=3326435481&category=21997

Can we use a crossover made for a 6 ohm impedence speaker on a 8 ohm speaker? I think the only concern here is the 044TI's as they are the only difference..

Do you have any idea or guess on the sonic impact of that upgrade? I really wonder if it worths such an upgrade

Ezel
05-12-2003, 02:46 AM
Hi..

Thanks for the graphs.. They look very similar. But as I am not a tech I can not make any judgement on it..

Do you think that 044TI could be used with the crossover of 250TI BQ? Can we upgrade with the newer crossover or do we have any limitations?

4313B
05-12-2003, 07:17 AM
It should be fine. Both networks use the same attenuation.

Ezel
05-12-2003, 07:22 AM
Thanks..

Sorry for asking over and over again.. DO you forsee any problem with such an upgrade?

4313B
05-12-2003, 08:40 AM
No I don't forsee any problems. But without doing it myself and hearing the difference I can't really say if it sounds better....

Ezel
05-12-2003, 09:12 AM
I do have the technical manuals in pdf format for both. But I don't have any idea or schematics on how to build a new network that will allow me bi-amping..

Actually I am willing to buy that N250TI BQ networks and keep them as spare. I am really happy with my Spaekers and I want to keep them alive for next 20 years.. For this I am trying to collect critical spare parts and stock them..

I am also looking for speaker repair kits specially for 044TI's or unused 044TI for replacements..