Crossovers

[[email protected]]

I bought these T26SG tweeters from GR Research and he refuses to return my emails, I'm asking for t/s peramaters so I can build crossovers,his website doesn't have the complete peramaters, anyone have info on these tweeters?

[fpitas]

T/S parameters for tweeters? What sort of enclosure did you plan to make for them?

[fpitas]

And T/S parameters aren't part of the crossover design process, even for woofers. You start with unwrapped phase and frequency response on-axis, and impedance vs frequency.

[DeZZar]

Crossover design requires you to have measured the frequency and impedance results once the tweeter is mounted in its desired location.

Everything you need to know is right there on the website....

SPECIFICATIONS:
Frequency Range 1k - 20kHz
Free Air Resonance 600Hz
Nominal Impedance 6 ohms
DC Resistance 4.5 ohms
Voice Coil Diameter 25 mm
Max Power 100 watts
Sensitivity 94 db
Face plate size 3.925"
Face plate depth .2"

The TS params that you would concern yourself with are ones to be considered when choosing the tweeter in the first place. FS, Ohms and Sensitivity. But as you have already chosen it, put it in place, measure it and go from there.

[fpitas]

Crossover design requires you to have measured the frequency and impedance results once the tweeter is mounted in its desired location.

Everything you need to know is right there on the website....

SPECIFICATIONS:
Frequency Range 1k - 20kHz
Free Air Resonance 600Hz
Nominal Impedance 6 ohms
DC Resistance 4.5 ohms
Voice Coil Diameter 25 mm
Max Power 100 watts
Sensitivity 94 db
Face plate size 3.925"
Face plate depth .2"

The TS params that you would concern yourself with are ones to be considered when choosing the tweeter in the first place. FS, Ohms and Sensitivity. But as you have already chosen it, put it in place, measure it and go from there.

I guess those are kind of T/S parameters. But yeah, those don't do much good for crossover design.

[billfitzmaurice]

Prelude to Spam. Is that by Debussy?

[fpitas]

A little known piece, featuring the Nocturnal Links overture.

[fpitas]

Actually kind of clever. Post something guaranteed to draw a crowd, then BAM spam link! I hope I finally find the essay writing service I've been seeking.

[fpitas]

If someone here doesn't have the measurements you need, you'll have to measure them yourself. There are threads here describing the necessary gear and methods.

[Wolf]

Pretty sure it's a Peerless India model tweeter, but AFAIK, those are no longer being produced.

Later,
Wolf

[Chris Roemer]

Tell us what you're building?

[[email protected]]

Already built, Dayton audio dcs380 15 inch classic subwoofer faitalpro 6fe200 professional midrange,2 of the T26SG tweeters from GR Research,if that's what they really are, don't trust the guy,as he won't return my emails, and so crossover networks haven't been built yet, my brother will be building them, he's been doing diy for 20+years and says he's still learning,as I don't know anything at all about building networks, I know how to build cabinets, and so I built these cabinets according to bassbox6 suggestion, parts express,3.85cf.for sealed box,3 way design, my brother says,he will build 12db crossover for tweeter, for power handling,as I have crown xli 800 to power these, I have wanted to build my own hi powdered diy speakers my whole life, I am 56 years old, and have some pretty serious health issues, and wanted to do at least this one thing before I croak, and now I did it, HAHAHA!!!

[djg]

Good luck.

[[email protected]]

Oh, and by the way, this is a 4ohm build, sorry bout that.

[DeZZar]

Best of luck with it. I guess the point remains though....at this stage you need actual measurements of all drivers in your cabinets to develop a crossover, not ts parameters. And a 12db network on the tweeter may or may not be what's required in the end...

Does your brother have the equipment for taking measurements and the software for modelling a crossover?

[[email protected]]

Yes he does, I don't remember the software for the crossover, but I do know that he has bassbox6, anyway won't be needing that,caus I've already built the boxes per part's express bassbox6 high fidelity suggestion , boxes are 38h 19w 14d,all sides rounded over,heveyly braced, internal volume 3.8cf,may be a little less caus of bracing. Crossover software might have been crossover pro or something like that, I'm not sure.

[[email protected]]

Think I'm in the right place, you guys sound like you know what you're talking about.

[[email protected]]

My woofers sensitivity is 93.6, midrange is 95, tweeter is 94, so I know we will have to pad down the mid a little bit, but the tweeter we may or may not.

[Wolf]

You will have to pad both when baffle step is accounted for.
Wolf

[billfitzmaurice]

That depends on the speaker placement. If it's close to a wall what wraps around the speaker will bounce back into the room. If it's flush mounted there is no baffle step. If placed on the floor that affects the low end as well. I prefer to do the same with BSC as I do with the rest of the components, measure the result in-room with typical placement to be sure of what, if anything, is needed.

[Wolf]

Fair enough, Bill. However, most of the time a build this large is not going in or on wall. Even on-wall or against a wall will have a slight loss due to the distances from baffle to wall.

[billfitzmaurice]

True, but the assumed 6dB loss to baffle step is seldom realized, unless the speaker is outdoors. Life and in room response are like a box of chocolates, you never know what you're going to get. That's why we always used to mount the crossovers externally, usually on the back of the box, allowing easy component substitution.