I wanted Altec Voice of Theaters, never could afford them if I did see some for sale. Saw Peavey SP5 on a website, went to the store, heard them, liked the SP2 better because the 15" woofer give better bass. The SP2 has a 2" piezo driven plastic horn, a 15" woofer, and a 1200 hz crossover. I love the sound, especially on top octave piano. Now I find out there are 6 or more vendors selling this design, although some have a smaller piezo driver. Yamaha, Mackey, American Audio, Electrovoice, all have versions of this design. There must be a lot of people that like it. I know some keyboard players on organforum.com are using different brands.
So who was first to do 15" woofer + piezo horn? I include some pictures gleaned from craigslist or peavey. Here is the primitive looking SP1.http://www.diyaudio.com/forums/attachment.php?attachmentid=181360&stc=1&d=1279897280 Here is an early SP2http://www.diyaudio.com/forums/attachment.php?attachmentid=181361&stc=1&d=1279897280 Here is a modern production SP2 http://www.diyaudio.com/forums/attachment.php?attachmentid=181362&stc=1&d=1279897280
I've got some really old Peavey T-300 High Frequency Projectors, which are 2 10" woofers and three piezo drivers installed in a fan shape. They sound good on high piano, but there is a very small sweet spot where the highs are focused. The SP2-XT has highs spread all over the room, and the peavey literature discusses a patent where the sound is focussed down from the speaker stand to people's heads. Works great in my living/dining room.
So who was first to do 15" woofer + piezo horn? I include some pictures gleaned from craigslist or peavey. Here is the primitive looking SP1.http://www.diyaudio.com/forums/attachment.php?attachmentid=181360&stc=1&d=1279897280 Here is an early SP2http://www.diyaudio.com/forums/attachment.php?attachmentid=181361&stc=1&d=1279897280 Here is a modern production SP2 http://www.diyaudio.com/forums/attachment.php?attachmentid=181362&stc=1&d=1279897280
I've got some really old Peavey T-300 High Frequency Projectors, which are 2 10" woofers and three piezo drivers installed in a fan shape. They sound good on high piano, but there is a very small sweet spot where the highs are focused. The SP2-XT has highs spread all over the room, and the peavey literature discusses a patent where the sound is focussed down from the speaker stand to people's heads. Works great in my living/dining room.
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Don't know 'who was first' with this kind op setup, but for home use I think this is a very nice project;
QSC SC-2150 Clone - AVS Forum
QSC SC-2150 Clone - AVS Forum
The 'modern' point source driver ('full-range', woofer, etc.) was invented in 1925 with the earliest 'modern' horn/reflex speaker AFAIK being a 1930 Bell Labs/W.E. 12" 'full-range'/800 Hz multi-cell design (can't find a photo ATM) that was quickly replaced with a cast alum. radial horn, then in 1936? a 15" woofer with a new 800 Hz multi-cell that remained in production with various horn, woofer models till the end of the 1970s ('80s if you include the Model 19) as the JBL/Altec Iconic, Valencia, 800 Hz Voice of the Theater in both pro and consumer versions. (JB) Lansing Manufacturing's version that would dominate after being bought out by Altec: http://www.lansingheritage.org/images/altec/catalogs/1942/page07.jpg
The Bell Labs/W.E. design would be resurrected after the Korean War and last through the '80s with various woofer models as the A8: http://www.lansingheritage.org/images/altec/catalogs/1966-vott/page4.jpg
GM
The Bell Labs/W.E. design would be resurrected after the Korean War and last through the '80s with various woofer models as the A8: http://www.lansingheritage.org/images/altec/catalogs/1966-vott/page4.jpg
GM
In what way(s)? I mean it depends on both the woofer's and horn's specs, so it's admittedly pretty easy to get a poor performing combo. The Altec M19 is considered by many to be the best overall sounding of the classic combos and the Geddes Summa easily outperforms it.
GM
I suppose that was mostly in pro applications. The 1" driver is crossed high to protect it. To my ear it doesn't mate well with the 15" woofer. A 10 or 12" woofer, yeah, sounds much better on vocals, especially.
But for domestic use it can work, true enough. Even I've done it. =) Usually need a big horn tho. Like the 811 cited in your examples.
But for domestic use it can work, true enough. Even I've done it. =) Usually need a big horn tho. Like the 811 cited in your examples.
Yeah, just look at how large the folded horn is to get a 1" to play low at high SPL and even then they had to use multiple horns with up to four drivers each for the really large venues just to spread the mono signal around the room. Even ~108 dB eff. horns can only do so much when limited to 8 W/driver.
GM
GM
Hmm, missed the piezo part. Don't know, though I first saw them in '50s era Motorola HIFI consoles. Still have a pair of 700 Hz cut-off/1200 Hz XO horns with large screw on piezos. I don't recall Peavey using the driver, but they were considered as strictly entry level rigs when they first hit Hotlanta in the mid? '60s. I remember trying to listen to a large (for the time) array at Rhythm City, but they were so shrill at high SPL that I had to make a hasty retreat, so may very well have been piezos. Mostly, I remember the crude fiberglass horns looking like they'd been made from a back poured JBL.
GM
Well, that just proves to me that speaker performance has a lot more to do with testing and quality control than it does with basic design. These SP2-XT's are not shrill at all, the best sounding speakers I've ever owned. Better than anything the church has bought. Thanks for the history GM, if any VOT's were ever sold here used they were quickly moved out to a bigger city where people can afford to spend some real money for them. We don't even have a boutique hi-fi shop anymore, just big box retailers and musician supplies.
Hmm, my 'piezo' comment pertained strictly to the early horns I tried to audition. Later horn drivers as early as the '70s definitely had bone-fide compression drivers, though to my ears they were at best on a par with Altec's IMO horrible 807 Symbiotik drivers, but at least they were a lot cheaper. Can't comment on more recent drivers.
Fortunately, I see Peavey now has an archive of sorts: http://www.peavey.com/assets/literature/manuals/sp2xt.pdf
I take issue with just how 'silky smooth' its Ti diaphragm is though as even JBL's best sounds like aluminum being ripped at high SPL if not damped with a mist coat of Dammar.
GM
Fortunately, I see Peavey now has an archive of sorts: http://www.peavey.com/assets/literature/manuals/sp2xt.pdf
I take issue with just how 'silky smooth' its Ti diaphragm is though as even JBL's best sounds like aluminum being ripped at high SPL if not damped with a mist coat of Dammar.
GM
Those early 2 piece SP2's in the picture at start post may be the shrill ones you are talking about hearing in 1970. They only sell for about $200 a pair. Whereas the SP2-XT is pulling about $300 each used, and SP2G with the speakon connector is getting $150 less than retail at about $450. Thanks again. Will look at the archive, have been to Peavey's site about the new model but didn't figure out that feature on the older ones. I did actually hear a VOT setup once in a theater in 1967, our band director told us to go have a listen. I heard them on Lord Jim movie, which had an indonesian gamalong orchestra soundtrack. Interesting and pleasant, but I had no live experience with those instruments to know what they really sound like.
Assuming the bass horns are FH1, I've suffered their excessive delay on many occasions, but the HF horn was a more abruptly terminated radial with no mounting flange, only glassed in metal mounting tabs to mimic the tabs on Altec sectoral horns, but I can't remember the JBL model it appeared to be a clone of and the stack was high enough that I couldn't see the HF driver.
The drivers I've seen though looked like some cheap EVs I've seen which in turn was offered as an Altec IIRC after being bought out by them, but I can't find the right info ATM.
GM
The drivers I've seen though looked like some cheap EVs I've seen which in turn was offered as an Altec IIRC after being bought out by them, but I can't find the right info ATM.
GM
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