035ti vs 035tia

[porschedpm]

Hi. I was working on my L100 update project which consists of:

L100 cabinets, with foilcals left intact. LF and HF adjustment knobs left in place but not used.
L100t Crossovers
128H-1 Woofers
104H-3 Mids
035ti Tweeters

I got everything put together but when I went to test drive them I found one of the 035ti's was blown. I have a pair of 035tia lying around so my question is this: Is the 035tia considered a direct replacement for the 035ti? Is the sensitivity approximately the same for both? Audibly are they about the same? As far as physical differences I'm aware of the differences in terminal placement. I appreciate any suggestions. Thanks.

[Earl K]

Hi

- I'm not a tweeter guy and,,,,

- I have no clue about any sonic differences between these two models ( can't you tell us since you own both types ? )

-There are some stated physical/electrical differences :

- Apparently, the newer 035tia uses a CCA "copper clad aluminum" voice-coil versus the originals' ( 035ti ) copper type voice-coil . An interesting thread called 035ti (http://audioheritage.csdco.com/vbulletin/showthread.php?t=450&highlight=035ti) , shows in chart form the electrical differences of a few tweeter models, as measured by John B.

- While you're pondering whether or not to just give your 035tia tweets a listen test, here's some more food for thought. It's in the form of opinions expressed about the preferred "listenability" of certain network types that use 044ti and 035ti tweeters (http://audioheritage.csdco.com/vbulletin/showthread.php?t=1981&highlight=035ti). Open to speculation is why the preference ? A cursory glance when comparing the different schematics shows an aircore inductor for the 4406 network versus the "others" that all use a laminate or iron-core type inductor . Note the positive comments made about a Charge Coupled™ 4406 variant .

<. Earl K

[porschedpm]

Hi Earl. Thank you for the response. I did my own searches on the Forum and found very little on the subject. But, between your links, my search results. and an impromptu listening test, I've come to the following conclusions:

1) The only physical difference between the 035Ti and the 035TiA is that the terminals on the 035Ti are set 180 degrees apart and on the 035TiA they are right next to each other. If changing from an 035Ti to an 035TiA, or vice-versa, you may need to cut out a small notch in the baffle to accomodate the terminal position change.

2) Sonically, it appears the 035TiA is the replacement for 035Ti, much as the 035Ti is the cheaper-to-manufacture version of the 044Ti. I compared an 035ti and 035tiA sided by side and could not tell a sonic difference, to my ears anyway.

3) As noted above in Earl's post above, the 035TiA uses a copperclad aluminum voice coil where the 035Ti uses just copper. Reportedly, the sensitivity of the 035TiA is about 1db different (lower I think). And there are some measured electrical differences (per the link in Earl K's post above). Even though there may be no noticeable sonic differences, there are enough other differences to conclude: if you're changing from an 035Ti to an 035TiA, always change them in pairs. I wouldn't recommend mixing an 035Ti and an 035TiA in the same speaker system.

[GordonW]

This is kind of hand-waving speculation, but... the L100T (in fact, the whole 'T' series, to varying extents) was generall regarded as being just a tad "bright", to some people. Subtracting 1 dB from the tweeter efficiency may not only WORK in a speaker using an L100T crossover, it might actually IMPROVE the percieved sonic balance to at least SOME people. I'd bet I personally would probably like the change, as I generally hate excess brightness...

Regards,
Gordon.

[johnaec]

OK - this is curious. According to the above messages, the 035Ti should have opposing connectors, yet the two from my L20T's have them next to each other, like the 035TiA. The 035Ti's from my L60T's do have the opposing connectors. I could just about swear the drivers from the L20T's haven't had new diaphragms - they're way too dusty and the screws are even a tiny bit rusty. Did JBL start putting 035TiA diaphragms into existing 035Ti magnet assemblies at some time during the changeover? :hmm: The standard 035Ti with opposing connectors is stamped 87 and the newer version is stamped 88. BTW - the mounting holes in all the baffles are of sufficient size that either will work in any of the enclosures.

Below is a pick of the three variations I have:

John

[hector.murray]

I had been contemplating a L100T myself. Now looking at your components and what was originall in a L100t, it occurs to me that you're not far from the mark. Correct me if I'm wrong, but isn't an L100t
2214H woof
104X mid
035tia tweet
L100t crossover
N'est pas?
So given your set of components, you're substituting a 128 for a 2214 to create a L100t variant.
This is a bassbox pro comparison of the 2 woofs. the 128 is in red. this assumes a 2.6 Cu ft box (L100) ported appropraitly for the woof in question. It doesn't look bad. By rights, the crossover was designed for the 035tia if my information is correct. You lose some overall power handling - 50% - but if it sounds good to you, well go for it!

[johnaec]

I myself am not building anything with either a 128H or 2214H in it, though I do believe the L100T has the 035Ti and the L100T3 has the 035TiA.

John

[hector.murray]

thanks for the correction

[DavidF]

As noted above in Earl's post above, the 035TiA uses a copperclad aluminum voice coil where the 035Ti uses just copper. Reportedly, the sensitivity of the 035TiA is about 1db different (lower I think). And there are some measured electrical differences (per the link in Earl K's post above). Even though there may be no noticeable sonic differences, there are enough other differences to conclude: if you're changing from an 035Ti to an 035TiA, always change them in pairs. I wouldn't recommend mixing an 035Ti and an 035TiA in the same speaker system.

I would bet you have the gist of the matter sorted out.

DavidF

[Mr. Widget]

I got everything put together but when I went to test drive them I found one of the 035ti's was blown. I have a pair of 035tia lying around so my question is this: Is the 035tia considered a direct replacement for the 035ti? Is the sensitivity approximately the same for both? Audibly are they about the same?


OK, so it's been a few months... today we had a tweeter fest here at Widget Works and among other things we checked out these two tweeters curtsey of Johnaec.

First is a plot of the 035Ti.

Red is on axis
Blue is 15° off axis
Green is 30° off axis
Purple is 45° off axis.

The second plot compares the 035Ti and a 035TiA... I'd suggest they are essentially identical... many of the tweeters we measured today had greater differences between several examples of the type due to manufacturing tolerances.

Widget

[edgewound]

The 035ti and 035tia are essentially acoustically identical...save for mfg tolerances. The 035tia diaphragm/flange assy is more of a self aligning mechanism upon assembly. It has a relief machined out of the outer edge of the top plate that alignment tabs slip over to center the voice coil in the gap. It also comes with small additional foam dampening pads that stack up like a cylindrical pyramid to calm down breakup modes in the origami inspired titanium dome. The 035ti assembly has to be manually aligned, then centered with a sweep generator to find the right position for no voice coil rubs. The obvious difference is in the terminal spacing...035ti is 180* apart....035tia are next to each other. Oddly enough this same tweeter motor/diaphragm assembly has been ingeniously(?) adapted to a phase plug/theaded horn mount and found a life as a compression driver(!) in two way JBL Pro(?) systems. Interestingly enough, you won't find a real pro using these compression drivers(?) in a live sound professional system....this was designed to be a 1" dome tweeter for mid-field and near-field recording studio monitors and home hi-fi systems. I have a feeling an accountant/MBA decided these should be passed off as compression drivers....resulting in more fries than McDonald's... pretty damn insulting to the pro audio community. But this is just my humble opinion...:banghead:

[Zilch]

It was a revelation, in fact.

I think of dome tweeters as having omnidirectional dispersion.

Nope. These are actually kinda "beamy" above 10 kHz.

Compare to 2404H.

[4313B]

I think of dome tweeters as having omnidirectional dispersion.

Techbot scanned and post information...

http://audioheritage.org/vbulletin/forumdisplay.php?f=12

Note dispersion characteristics of systems like the L212. 066 1" phenolic dome with aluminum shell.



Snipet from a JBL bookshelf system using the 033 1" phenolic dome. Filters are 6 dB/octave.

[tortello]

It also comes with small additional foam dampening pads that stack up like a cylindrical pyramid to calm down breakup modes in the origami inspired titanium dome.

Hello Edgewound,
I've just bought two original JBL D8R035TIA diaphragm replacement.
The kit comes with two "rubber" circles, the bigger (dia mm.22) seems to be foam, the other one (dia mm.6) is made with harder material. I think the foam has to be fitted between center magnetic pole and titanium dome (n°1 in thios drawing http://www.2shared.com/photo/oGyAV8Vl/035TIA.html ) but... the little one? According on your opinion, it should be putted in the N°2 position. Is this correct?
Thank you very much,
best regards

Marcello

[tortello]

Hello Edgewound,
I've just bought two original JBL D8R035TIA diaphragm replacement.
The kit comes with two "rubber" circles, the bigger (dia mm.22) seems to be foam, the other one (dia mm.6) is made with harder material. I think the foam has to be fitted between center magnetic pole and titanium dome (n°1 in thios drawing http://www.2shared.com/photo/oGyAV8Vl/035TIA.html ) but... the little one? According on your opinion, it should be putted in the N°2 position. Is this correct?
Thank you very much,
best regards

Marcello

Please, I need help!! :blink:
TIA, Marcello