Super tweeter

[David12]

I have just bought a pair of fostex t90a super tweeters and are wondering the best way to wire them in capacitor or crossover as have never done something like this before any advice would be greatly appreciated

 

[BDWoody]

Welcome!

Not something I've done, so I have no input on how to best wire it in. I do wonder what led you to doing this? What speakers are you using them with?

 

[DSJR]

In the first wave of 'Super tweeters' (I'm thinking of a lozenge shaped Tannoy one from yesteryear), they actually came in at a very audible 8 - 9kHz so their addition was obvious. These days, fancy tweeters go out to 40kHz or so, some often with nasssssty razor sharp peaks at around these supersonic frequencies (KEF/B&W to name but two brands).

So, if you want to go ahead, easiest way would be to put a series cap (no real idea of value but 0.5uF may be a starting point). No idea what speakers you have, but as I said above, the tweeters you have may well negate the need for re-enforcement up top

 

[Deleted member 21219]

There can be problems with super-tweeters. Some of the problems and an overview of six models with their response curves is on this page detailing The Loudspeaker model of DIY projects from Troels Gravesen. I hope it's of some help to you. (Your Foxtex t90a is in the "measurements" section of his second model.)

The-Loudspeaker

Second model, with tweeter measurements:

The-Loudspeaker-2

Jim

 

[voodooless]

I have just bought a pair of fostex t90a super tweeters and are wondering the best way to wire them in capacitor or crossover as have never done something like this before any advice would be greatly appreciated

Hi there, and welcome! What speakers are you using these with? With any normal speaker, you’d think this kind of stuff isn’t needed. It may be useful to accompany large format compression drivers in big horns. Generally if used with speakers that already cover the same range, you can expect some interference happening due to the center to center distance being too large. This may be an interesting effect, but will certainly not give you a faithful reproduction.

 

[sergeauckland]

I would ask first what are you trying to achieve with the supertweeters? As has been mentioned by others above, modern loudspeakers already go reasonably flat to 'supertweeter' frequencies, so adding supertweeters won't accomplish anything that can't be done with a slight twist of the treble tone control, or indeed an equaliser.

Also as mentioned above, most supertweeters start below 10kHz, so their effect is immediately obvious, and won't be an improvement in accuracy.

In my view, a solution looking for a problem.

S.

 

[David12]

I would ask first what are you trying to achieve with the supertweeters? As has been mentioned by others above, modern loudspeakers already go reasonably flat to 'supertweeter' frequencies, so adding supertweeters won't accomplish anything that can't be done with a slight twist of the treble tone control, or indeed an equaliser.

Also as mentioned above, most supertweeters start below 10kHz, so their effect is immediately obvious, and won't be an improvement in accuracy.

In my view, a solution looking for a problem.

I would ask first what are you trying to achieve with the supertweeters? As has been mentioned by others above, modern loudspeakers already go reasonably flat to 'supertweeter' frequencies, so adding supertweeters won't accomplish anything that can't be done with a slight twist of the treble tone control, or indeed an equaliser.

Also as mentioned above, most supertweeters start below 10kHz, so their effect is immediately obvious, and won't be an improvement in accuracy.

In my view, a solution looking for a problem.

S.

I am using klipsch r50pm speakers with r121sw sub being as they are active there is no way that I have found to do these minor adjustments was recommended these because they work well with bookshelf speakers or so I was told

Welcome!

Not something I've done, so I have no input on how to best wire it in. I do wonder what led you to doing this? What speakers are you using them with?

I'm using klipsch r50pm bookshelf speakers with a 12 inch r121 sub thanks

In the first wave of 'Super tweeters' (I'm thinking of a lozenge shaped Tannoy one from yesteryear), they actually came in at a very audible 8 - 9kHz so their addition was obvious. These days, fancy tweeters go out to 40kHz or so, some often with nasssssty razor sharp peaks at around these supersonic frequencies (KEF/B&W to name but two brands).

So, if you want to go ahead, easiest way would be to put a series cap (no real idea of value but 0.5uF may be a starting point). No idea what speakers you have, but as I said above, the tweeters you have may well negate the need for re-enforcement up top

I am using kilpsch r50pm bookshelf speakers with a r121sw 12 inch sub

 

[voodooless]

kilpsch r50pm

I don’t see a reason for a super tweeter for these? Why do you think you need one?

 

[mhardy6647]

I have just bought a pair of fostex t90a super tweeters and are wondering the best way to wire them in capacitor or crossover as have never done something like this before any advice would be greatly appreciated

This is what I did with 'em in my quest to add some tippy-top treble to Altec 604E Duplexes.


(beta test )






Don't be afraid to cross them in very high (depending, of course, on your specific need). In my case, e.g., the nominal XO frequency is very high (nominally 20 kHz!) -- but don't be taken aback. The high sensitivity of the driver and the mild slope of the XO combine to give plenty of output in the audible range even for my distressingly elderly ears.

EDIT: The T90a is a refreshingly sweet sounding high-ish sensitivity horn tweeter with surprisingly extended response.
Not cheap, though.

https://www.fostexinternational.com/docs/speaker_components/pdf/t90arev.pdf

 

[David12]

Thanks just what I was looking for

 

[voodooless]

This is what I did with 'em in my quest to add some tippy-top treble to Altec 604E Duplexes.

This makes sense. The speaker alone cannot do 20 kHz on its own.

But spending as much on a super tweeter as the bookshelf it’s supposed to accompany, which has no issues giving output up-to 20 kHz, just doesn’t make any sense.

 

[mhardy6647]

Supertweeters in the 1980s...

source: https://hercshideaway.blogspot.com/2015/03/herc-loves-dak-part-three.html

Spoiler

This post is meant as a joke. A joke, OK?! Although these DAK/BSR abominations, like many others, really did happen. It was the '80s... interesting times.

 

[dpturner]

Supertweeters in the 1980s...

View attachment 351024
source: https://hercshideaway.blogspot.com/2015/03/herc-loves-dak-part-three.html

Spoiler

This post is meant as a joke. A joke, OK?! Although these DAK/BSR abominations, like many others, really did happen. It was the '80s... interesting times.

bought these "tweeter arrays" back in the day. eventually gave them to a friend, who i think still uses them.

 

[dualazmak]

Welcome to our ASR Forum!

My DSP-based multichannel multi-SP-driver multi-amplifier fully-active stereo audio setup having tuning and protection capacitors for supertweeter FOSTEX T925A dedicatedly and directly driven by a HiFi stereo integrated-amplifier would be of your reference and interests, I assume:
My latest system setup including T925A can be found here #774 on my project thread;
- The latest system setup of my DSP-based multichannel multi-SP-driver multi-amplifier fully active audio rig as of August 3, 2023: #774

Edit: T925A is still internationally available:
https://www.fostexinternational.com/docs/speaker_components/HornTweeters.shtml
https://www.fostexinternational.com/docs/speaker_components/pdf/t925arev.pdf


Just for your reference, let me share the links to some of my major posts on supertweeter FOSTEX T925A:

- Overhaul maintenance of super-tweeter FOSTEX T925A and further signal fine tuning thereafter: #485 (including the specification of T925A with 3.0 microF high-pass capacitor and 10 microF protection capacitor in addition to DSP's -12 dB/Oct high-pass/low-cut at 6 kHz)

- Unique super tweeter physical alignment (positioning) in the project : #027

- Protection capacitors!! #184, #886, #888, #890, #901, #906

- Very interesting recent discussions on supertweers on the thread "Are Super tweeters worth it?": posts #43 through #61

- Frequency (Fq) responses in the completed system measured by using “cumulative white noise averaging method” under the present standard crossover configurations and relative gains_Part-6_Summary, discussions, and a little step forward: #404, #405-#409

- Even Greg Timbers uses "reasonable and budget" Pioneer Elite A-20 for compression drivers (super tweeters) in his extraordinary expensive multichannel stereo system with JBL Everest DD67000 which he himself designed and developed: #435

- Summary of rationales for "on-the-fly (real-time)" conversion of all music tracks (including 1 bit DSD tracks) into 88.2 kHz or 96 kHz PCM format for DSP (XO/EQ) processing: #532

- Excellent Recording Quality Music Albums/Tracks for Subjective (and Possibly Objective) Test/Check/Tuning of Multichannel Multi-Driver Multi-Way Multi-Amplifier Time-Aligned Active Stereo Audio System and Room Acoustics; at least a Portion and/or One Track being Analyzed by Color Spectrum of Adobe Audition in Common Parameters:[Part-11] Violin Music: #643; Detailed descriptions on safe and flexible on-the-fly relative gain control for supertweeters (and tweeters, if needed)

- Again, summary of my rationales and pros of analog-level relative gain (tonality) controls in addition to gain controls in DSP configuration: #911

- [Thread] Music for Testing Treble (High Frequency) Sound

- [Thread] An Attempt Sharing Reference Quality Music Playlist: at least a portion and/or whole track being analyzed by 3D color spectrum of Adobe Audition