Acousta Voice EQ

[zevon329]

I have an old (70's) Acousta Voice equalizer that I'm trying to find some info on. This has all individual frequency modules wired together in series, and the front controls are rotary. The only info I can find is that I believe it was one of the first room eqs ever built. I can't find any serial numbers for the unit, but it's definitely a classic. Does anyone know anything about this unit?

[scott fitlin]

Can you post a picture of the unit?

I used to use an Acousta Voicette 729A before we graduated to the Altec 16 somethings, and both the 729A and the pro 16somethings had slide faders for the EQing filters.

In one of my audio engineering books, from the late 50,s, there is a picture of an Altec motion picture theatre EQ that has rotary controls, so when I get home I will definitely look this up! If this is what you have its not from the 70,s, it could be way older than that!

Have you tried using it? how does it sound? I am a fan of White Instruments EQ,s! But Im curious to what you have.

Regards, Scott.

[zevon329]

Just in case it wasn't clear, this eq was manufactured by Altec, or at least all of the frequency modules were.

[scott fitlin]

I looked in the book I said has a picture of an old Altec Graphic EQ, but, this EQ is faders, with what appear to be knobs on them! So, it looks like rotary but isnt! Its also only six or seven bands and was for movie theatres!

Whatever you have, its a mystery to me!

[zevon329]

I'll take some pictures tonight and have them up by tomorrow. The EQ works, although it's pretty harsh. I read that this was first introduced around 1967 by Don and Carolyn Davis, who toured the country showing how Altec's new EQ could help sound reinforcement. There's no model # on the unit, so this may well be one of the earlier laboratory models. Anyway, it's a classic piece of Altec's history. I'll post some pics and any other info I can find. Thanks for your help!

[zevon329]

I've got a couple if pictures of the EQ, but I'm not sure I can attach them on this message board. I'll try sending them to you direct. The EQ has 24 bands, and the hi/low are 100 hz and 12khz. Not much bandwidth, but hey, this was like 1970. You can see the Altec logo and the green paint, but there's no model # anywhere.

[scott fitlin]

Hi Warren, I got your pics of this EQ, and Ive never seen one like this, but its definitely an Altec!

Its more similar to the White Instruments EQ,s with the rotary controls, and we had the 1650A,s in here in the later 70,s to early 80,s. But our 1650,s had faders, as did our 729A which we had before the 1650,s!

Ill offer a guess as to what this unit is, possibly its an early version of the 1650 1/3 octave EQ? Maybe Todd would know if they, at some point in the 70,s, changed the faceplate of the 1650 series, and the changed the controls from rotary to faders?

Interesting EQ, though!

[RClark]

sounds like the 9013/9014 variety-----i too have several units of the type you refer to------they date from the late 60's early 70's---------they were all passive and were extremely expensive even by todays standards---------opening one of the modules will show you why-------each "acousta-voice" contractor had a master set of filters and would use it to tune a system-----there was a one octave set and a 1/3 octave set---------afterwards they would only wire the filters used for each job to save cost-----thats why it is not uncommon to find a set without all the 1/3 octave frequencies represented--------they were unbalanced 600 ohm units and required proper termination for accurate response--------even today it would be difficult to find a filter set that produces better specs since the units were all passive and used tight spec components----------RC

[scott fitlin]

Thats a very good possibility. The 90xx series is before I got into audio, but I forwarded the pictures of the EQ to Todd, maybe he also has answers about this EQ!

[zevon329]

I think you may be right. From what I read, Acousta Voice engineers would go to theaters, music halls, etc, and set the eq to the room with a lot of lab equipment. It makes sense that they would only build what was necessary, hence no factory installed model #. There are 24 bands on it that don't really follow the 1/3 octave spacing, probably because they didn't need them all. Thanks.