VOICE OF THE THEATRE vs QSC SC-1120 speakers

[Allan Barnes]

BACKGROUND - I bought this 1940s cinema and am turning into a TRIPLE screen. I am upgrading everything.. Behind the screen I have these vintage MONSTER SPEAKERS (6 of them) which I soon will test. FYI the cinema was still using them for BLACK ADAM. Your opinion, should I sell these old speakers AND buy new? And does anyone have SC-1120 speakers in stock? Suggestions and Abuse welcome.

[Gordon McLeod]

If they are A4 then I would do the Lonny Jennings mods and depending on the HF horn replace the horn and Biamp them this is a A4

[John Eickhof]

As an old 'dyed in the wool' Altec man (worked and trained by Atec service co / Altec-Lansing ) and was an Altec dealer for decades, I have to agree with Gordon that the A-4 and the and A-7 as well as early wide wing A-5 speaker if upgraded to high power components and later HF horns would be very suitable for 'knock them out of their seats' sound. However the A-series models, A-2, A-2x, A-4, A-5, A-6, A-7 and A-8 'Voice of the Theatre' were designed under a different theory and less dynamic sound sources, they were based on what were high efficiency-low power sound when Jim Lansing and other Altec engineers developed their speakers the rear loaded horn cabinets were designed to give a max gain and wide field under low wattage medium fidelity limits of early sound. They would develop 108-110 db at 1000hx 1 watt input at one meter in front of the speaker yet still deliver 100 feet or more with little loss, however the band of frequency was pretty narrow. The advent of magnetic recordings and later digital forced development of higher powered systems with more dynamic range of sound and less efficient loudspeaker designs and the old Altec stuff could not handle the power. starting right at the crossover... the cross overs and speaker components could take 35-75 watts max before saturating, distortion, or self destruction! Upgrading the components would be less costly then new loudspeakers but there are advantages to the newer designs. Personally, I have vintage A-7s in my theatre with upgraded components to handle up to 300 watts but in ordinary use the old Altecs are being driven with 5-10 watts and tuned up fine for digital. Just my 5 cents worth! One more thing...if they are A-4s and the screens are not very wide, I would go with newer speakers that have a narrow dispersion or because of the sheer size the large boxes will be so close and have a wide dispersion that channel separation would be less evident...

[Steve Guttag]

I, almost, feel like this is a setup question. The SC-1120 is QSC's smallest and is pretty much a home-theatre speaker or one for a commercial sized theatre on the order of a closet/screening room (it just has a 12" woofer with a 95.5dB 1w/1m sensitivity and a 300W PN power (combines low sensitivity with low power handling). Conversely, if you do have large Altec speakers, particularly Altec badged and not the Simplex XL varieties of the "Voice of the Theatre", then you are comparing apples to oranges. If the theatre is going to be significantly smaller (less wide, in particular), an A4 will become less and less of a good choice. Even with it becoming less deep of a theatre, the A4 becomes less and less of a good choice as one has to be on the order of 20-feet away from it before the HF and LF sections really converge on the listener. It is designed for a large room and with a balcony (hence the vertical mouth of the horn).

There are numerous models of "Voice of the Theatre" so one would need to know which one(s) you have versus the room they would go into to make any judgements on their suitability. Likewise for any modern speaker. I can't think of ANY room where an SC-1250 and an A4, A5, A7, A8 would be on the same list of contenders (though the A8 is getting closer but it is a vastly different animal than the larger speakers).

[Mark Gulbrandsen]

I've used SC-1120's at least twice and perhaps three times. The first place I used them was in a 34 seat theater, and they were perfect for that. The dialog was very nice and combined with the appropriate QSC subwoofer, the system as a whole is hard to beat for small cinemas.

[Steve Guttag]

Exactly, a 34-seat theatre...small. I suppose one could use an A7 in that sort of theatre but the cabinets are going to be almost touching...perhaps the A8 (never my favorite).