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Discussion Starter #81

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Looks like there is a "back" - http://www.parts-express.com/pe/showdetl.cfm?partnumber=264-870
But no photo of the back so we can't tell; can always make up a little wood box and glue to inside - I known some DIY guys use small "tin cans" as a chamber.
I'll try to post a picture of the "port" in the rear of the Tang Band Tweeter. It's teensy compared to the "Holes" in the magnet of a 18" subwoofer.
I'm wondering if the "port" requires some enclosure beyond the resonant chamber which is already designed into the rear cover. I haven't done any analysis using WinISD. Can you even model a tweeter in WinISD?
On an unrelated subject, what about "baffle step compensation". What about edge diffraction?
Who has those answers?:ponder::ponder:
 

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I'll try to post a picture of the "port" in the rear of the Tang Band Tweeter. It's teensy compared to the "Holes" in the magnet of a 18" subwoofer.
I'm wondering if the "port" requires some enclosure beyond the resonant chamber which is already designed into the rear cover. I haven't done any analysis using WinISD. Can you even model a tweeter in WinISD?
On an unrelated subject, what about "baffle step compensation". What about edge diffraction?
Who has those answers?:ponder::ponder:
Baffle step is more for the frequencies and distances involved for a midrange driver.
 

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Baffle step is more for the frequencies and distances involved for a midrange driver.
There's quite a wide ranging discussion about baffle step compensation. Some insist you gotta have it, others say you can compensate using other means, most acknowledge a condition exists that MAY influence the audio product. I'm still unsettled.
 

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Discussion Starter #86 (Edited)
I'm sure BSC is needed on some speaker projects - however one more reason to build "satellite boxes".

The imaging on this last pair of SF/Vifa speakers is outstanding (no BSC) also the TB speaker on the first post is also 5 out of 5 stars. I need to measure the TB pair, like to see the response since I did use the xo from another-similar build.

SF/Vifa build....I asked MS to quote a kit price for woofers/tweeters/prebuilt xo with upgrade parts (Clarity Cap and 14 awg wire) $250 per pair.

That's about a $100 less than the SR71 speaker kit:

http://www.madisoundspeakerstore.com/2-way-speaker-kits/zaph|audio-sr71-kit-pair-parts-only/

I had a pair of SR71's...okay I guess, I didn't have them long to appreciate them.


Good read: http://news.cnet.com/8301-13645_3-20113895-47/can-sound-quality-be-measured/?tag=cnetRiver
 

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The article you reference is where I'm at. However, it's those pesky engineers that, over time, have brought us to this point of audio nirvana. The overall engineering and technology movement in audio/video technology has obviously been in the right direction.
Us DIYers have a place in the scheme of things though too. Without US there would have been no search for a speaker capable of reproducing 10Hz @ 110db. There would also NOT be audio crossover capacitors the size of Campbell Soup cans costing $899.00 each! There would be no 1000 watt amplifiers that weigh only 7lbs. So . . . . . never feel like your OWN projects aren't worthy of a deep discussion with others here on Home theater Shack.
 

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The imaging on this last pair of SF/Vifa speakers is outstanding (no BSC) also the TB speaker on the first post is also 5 out of 5 stars. I need to measure the TB pair, like to see the response since I did use the xo from another-similar build.

SF/Vifa build....I asked MS to quote a kit price for woofers/tweeters/prebuilt xo with upgrade parts (Clarity Cap and 14 awg wire) $250 per pair.

That's about a $100 less than the SR71 speaker kit:
Which SF/Vifa build are you referencing?

I'm using the same tweeter as used in the SR-71s (Seas 27TDFC) in my current 2 ways with a Peerless 6.5 inch 830874 woofer. That tweeter IS excellent.
Comparing the two tweeters, the Tang Band TW 28-537SH vs the Seas 27TDFC,
The Tang Band is much more robust, better build quality, and $20 bucks cheaper. Subjectively, the two have similar audio performance characteristics with a slight edge going to the Tang Band because of lower harmonic distortion. The distortion issue I haven't had a clear chance to evaluate. I'm still in the build stage.
I think one of the reasons the Tang Band tweeter is not more popular is the fact that the performance data lists the "RATED POWER INPUT" at only 12 watts and the "MAXIMUM POWER INPUT" as 100 watts.
A 12 watt tweeter is NOT what any of us are interested in, even with a 4th order X-OVER in place to protect it. The 100 watt "MAXIMUM POWER INPUT" is confusing. Just exactly what does that mean? It's not the usual language used to describe a drivers power capability.
Anyway that's the first thing I checked when I received the Tang band tweeters. I hooked a tweeter up with a 3.9 μF capacitor and began to play music while increasing the volume little by little until my ears hurt.
The fact that it played at what I assumed was at least 95db was proof enough to me that the tweeter had enough power capability to play at volumes loud enough for my average listening environment without damage.
 

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Discussion Starter #91
The thread jumps around a bit, scroll back to post #52.

If you like the sound of a "small 2-way" these are really working well.

Big Bold sound!!!
 

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I've got a bunch of two ways and some 3 ways. I've been experimenting for years.
I'm always looking for new driver combinations and my current duo, Beyma/Tang Band, looks the best so far . . . . on paper.
I've decided lately I need to play louder, don't know why except one of my buddies came to visit and wasn't impressed by my mains. He thought they should play louder. I measured them at 102db at + 6 on the receiver. they were beginning to stress at that volume. That speaker has a 6.5" woofer and a Seas tweeter.
So now I'm working with the Beyma 10" and the Tang Band Tweeter. The Beyma is louder than the 6.5 woofer in free air. The Beyma "sound" is very pleasing to my ear. I'm working on the x-over trying to use as few parts as possible and using the best caps, coils, and resistors I can afford.
I'm one of those DIYers that thinks there IS an audible difference between one capacitor and another. Coils and resistors, of course, can reduce the driver output so a coil with fatter wire offers less resistance.
I'm thinking I can eliminate a BSC (baffle step compensation) by reducing the nominal size of the ported enclosure PLUS tuning the box higher than the Fs of the driver by a slight bit. According to WinISD the upward slope of the driver response as the Hz goes down in a smaller box tuned a little higher would match the upward slope produced by a BSC. Less parts in the signal chain is a good thing. Less parts to add distortions or coloration.
 

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Capacitors can play a big part in the sound of a speaker.
When I made my speakers (A long time ago) there was not the selection of high quality ones that are available today. Interestingly a supply of low cost, high quality, high voltage caps were readily available right under our noses - fluorescent light power factor capacitors!
 

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Capacitors can play a big part in the sound of a speaker.
When I made my speakers (A long time ago) there was not the selection of high quality ones that are available today. Interestingly a supply of low cost, high quality, high voltage caps were readily available right under our noses - fluorescent light power factor capacitors!
`
LOL, I've never used a fluorescent light capacitor for anything but the light.
What is the Mf rating if you know? I'm guessing the voltage would be somewhere around 200V.
AND as far as their being right under our noses . . . . well maybe if you're Karrem Jabbar.
 

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`
LOL, I've never used a fluorescent light capacitor for anything but the light.
What is the Mf rating if you know? I'm guessing the voltage would be somewhere around 200V.
AND as far as their being right under our noses . . . . well maybe if you're Karrem Jabbar. :rofl:
I have a 2.8 uF and 4.0 uF 440 VAC along with a 32uF 330 VAC (we run 240 VAC mains here)
 

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Discussion Starter #99 (Edited)
This foil Goertz inductor was only $3 more than the wire wound; same awg.

The bass is tighter, however, it's raining here so hard to tell really.

(BR boxes sound deeper when it rains)

EDIT: watched some moves last night, really great tight bass, subwoofer sound.
 

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