Category Archives: Altec

Altec full-line 1976 catalog

Altec_1976_Catalog_Cover70’s months at P S DOT COM continues with a fresh scan of the complete 1976 Altec pro audio catalog, complete with pricelist.  Presented in two parts due to file size.

DOWNLOAD PART 1: Altec_1976_part1

DOWNLOAD PART 2: Altec_1976_part2

Altec_Cinema_1976Above: Altec’s classic Cinema loudspeakers, including (LR) the 1,300lb A2 speaker.

Products covered, with text, specs, and photos, include: Altec 1240B, 1208B, and 1218A ‘Voice of the Theatre’ speaker systems; 1221A stage monitor, 1219B speaker and 1224A Bi Amplifier, Altec A2, A4, A4X, A5X, A7-8, A7-500-8, and A-8 VOTT; Altec 9845A, 9844A, 814A, 849A, 210, 211A, 612C, 614D, 815A, 816A, and 828B speakers; 604-8G, 620-A, 9844, 9845A, 9849-8A, 9849-8D studio speakers, Altec 203B, 311-60, 311-90, 803B, 805B, 1003B, 1005B, 1505B, 32B, 511A, 511E, 31A, 511B, AND 811B horns; Altec 1211A and 1217A column loudspeakers; 417, 418, 421, and 425 musical instrument speaker; plus many many more speakers and speaker components.  We also see the Altec 1220AC mono console, 351C, 1590C, 159B, 1594B, 9440A, 1224A, 1609A amplifiers and 1606A, 1607A, 1608A, and 1611A mixer/amps; Altec 1628A, 1592B, 1599A, and 1589A mixer/preamps; 1603 coupler, 1605A expander, 1612A compressor, 1650 EQ, 9430A digital delay (looks like a lexicon-made unit) and 9880A filter; a load of other bits and bobs, and microphones including the Altec 650, 654, 656, 655, 677, 676, 668, 699, M53, M54, 624, 626, and 687.

Outboard_Altec Altec_VOTT_1976 Altec_Studio_Speakers_1976 altec_Mics

Novel Vacuum Tube / Diode Compressor: 1950

Download a short piece from RADIO-ELECTRONICS, 1950, on the subject of a DIY audio-compressor:

DOWNLOAD: DiodeCompressor1950

This promises to be an interesting unit.  It’s designed (like a Shure Level-Loc) for Mic-Level-In, Mic-Level-Out, but that could pretty easily be changed for balanced-line operation by omitting the first 12AT7 stage and using a modest step-up transformer (maybe 1:3 or 1:5) going into the input level pot, and then adding another output stage and output transformer.  (Since 1/2 of the 2nd AT7 is unused, I am thinking: eliminate one of the 12AT7s entirely, build this circuit minus the first stage using one 12AT7, and then add the output stage from the Altec 1566).  The unit promises to add distortion, and there is some sort of low-pass network before the 3rd grid that will also need some sort of variable components added in order to control the quality of that distortion.  My biggest question, though: will plain ‘ole IN4007 Diodes work in the circuit?  I plan to build this thing soon and all questions will be answered… always looking for new (old) sources of novel grit+crunch….

Altec Public-Address in the Seventies

Above: this one caught me by surprise.  Neil Young endorses Altec PA kit in 1971.  We see the Altec 1210A console and 1205A powered speakersApparently Don Ellis and Merle Haggard were also endorsers at the time. 

Today: some early ‘seventies adverts for Altec PA gear.  Altec equipment was no longer state-of-the-art studio gear by this period, but they seem to have enjoyed continuing success with sound reinforcement.  For a full catalog download that discusses much of the equipment featured, click here and visit this earlier post.

Above: The Altec 1217A.  Powerful enough for ‘Boogie Rock.’

Above: Altec’s young and photogenic employees circa 1974

Above: (it’s 1974): ‘Rock’s grown up.  The Group’s grown up… Altec was there when the magic of rock and roll arrived. Woodstock.  Monterey.”

Altec Theatre Equipment 1955

Download the four-page 1955 ‘Altec Stereophonic Sound Equipment for Theatres’ brochure:


Units discussed, with text, specs, and images, include: A150-C 4-channel preamplifier; 1530T power amp; 1520T amp; 625 and 629A speaker systems.

The Altec ‘Voice of the Theatre’ (VOTT) auditorium/theatre speaker systems are oft discussed; the A5 and A7 and all the other numerous variants (data on which can be found elsewhere on this site) provided high volume and excellent frequency response in large motion-picture-exhibition theaters in an era when amplifier power was limited by the available technology of the day.  This unusual catalog provides a good look ‘backstage’ at the various bits+bobs that Altec made for the projection booth and as support for the VOTT systems.

Mics of ’56

Above: Belden 8411, 8422, and 8412 microphone cable.  I still use Belden 9451 for most studio hard-wiring tasks, although I have to admit that I am very devoted to Canare StarQuad for actual mic cables.  Anyone out there prefer Belden mic cable to the Canare?

Above: The Altec 680A omni dynamic.  This one looks very strange.  I am very curious to know what it sounds like.  Anyone?

The Altec M20 condensor microphone.  These seem to still be is use in studios.  I hope I turn up one of them soon…  folks seem to like them a lot.


Original EMI-modified Altec compressor on eBay: UPDATE

image source

NOTE: the above unit eventually did sell on eBay for $35,000.  See below for scan…

Here’s something that you don’t see everyday.  Courtesy of this eBay auction, an apparently original EMI-modified Altec 436B.  Buy it now for $55,000 (fifty-five-thousand) US dollars.   If this price seems absurd (and it surely is optimistic at best),  I will point out that the seller claims (and he/she may very well  be correct) that this particular unit was in fact used on numerous Beatles recordings.  The particular quality of its compression, pumping, and mild distortion were integral to creating the vocal and drum sounds of the most widely-heard and widely-copied pop/rock recorded sounds in the entire history of sound recording.   Add to that likely provenance the fact that only a handful of these units were ever made and you have a very unique piece of audio history on the block.

image source

Here’s a shot of the rear of the unit.  A few things worth noting: the JJ multicap (above the blue LCR cap) is of recent manufacture, indicating recent servicing.  The lineup of three tubes and only two audio transformers indicates that this unit began its life as a 436(x) compressor, not a 438(x) mic pre/compressor.  The mains transformer (far left) was necessarily replaced to facilitate easier use in a 220v country.  My biggest question (and please, readers, fill me in… ) is:  what is that unit above the 6AL5 tube?  Is it a 2nd output transformer to allow of use of a T-pad attenuator on the output while retaining output balance (IE., the T-pad would go between the two transformers)?

image source

Getting back to the front panel, we see evidence of the modifications that EMI made in order to make the 436B more useful in the studio.  From left to right: a ‘balance’ push-button switch (not sure what this is, but i image it might have something to do with balancing the vari-mu action of the two halves of the gain-reduction tube?  not sure how a pushbutton switch would be implemented there?). Next, a ‘recovery’ or ‘release’ control (self explanatory), then factory ‘input’ attenuator control, and to the right of the meter an output attenuator.

Anyway…those of you who have been following PS dot com for a while will know that I have a tremendous interest in these Altec compressors; I have restored them, modified them, scratch-built them, and use one regularly in the studio.   Here’s some links to catch up:

History of the Altec 43(x) compressor and its relation to the EMI RS 124

Adding a balanced output attenuator to an Altec compressor

Modifying an Altec 438a compressor to gain many of the EMI RS124 features



Studio test of obscure circa 1965 Altec dynamic microphones

L to R: Shure SM57; Altec 684 Omni; Altec 682 Cardiod; Altec 683 Cardiod

Altec made a great number of different microphone models in the 1950s and 1960s.  A certain few of these are still widely used in recording studios today: most notably the 639 ‘Birdcage’ dual-element microphone (see here and here) and their various small diaphragm ‘Laboratory’ condensers (see here, here, and here).

During this period Altec also made a variety of conventional-looking dynamic microphones, some of which have quite good specs on paper.  Today we’ll be having a listen to the Altec 682, 683, and 684.

I’ve prepared three stereo audio tracks which all document an identical solo guitar performance which we tracked in the big room at Gold Coast Recorders.   In each of the three tracks, you will hear a new-ish Shure SM57 in the left speaker, and the selected Altec mic in the right speaker.  I chose an SM57 as a reference because it is a microphone that most of us are very familiar with and it is often used to mic electric guitar amps.  I placed the mics a big further back than I would generally use a dynamic-mic on a guitar amp in order to minimize any differences that might result from the slight variation in mic placement in relation to the amplifier.  All signals were taken from the microphone into identical Sytek mic preamps and then directly into Aurora Lynx convertors and into Protools.  No processing whatsoever was used other than minimal Digidesign MAXIM on the bounce-buss to ensure strong playback level; it was taking off 0.3db at most.

Levels were matched initially by running a 1K tone into the guitar amplifier and then fine-tuned on playback to within the tightest possible margin.  The 684 Omni required 30% more gain to reach an equal level; the other three mics were within 5% or so of each other in terms of output.

Alright now that you’ve seen the setup, here is the audio:

SM57 vs Altec 682: SM57L_682R

SM57 vs Altec 683: SM57L_683R

SM57 vs Altec 684: SM57L_684R

Have a listen and draw your own conclusions.  My quick assessment: the 682 sounds pretty similar to the 57, but IMO a lot prettier, a lot more detailed, and just more presentable in general.  The 683 sounds thinner than the 57; bass is notably lacking and there is an aggressive character to the mids.   Not sure that I would ever select this mic for anything.  The 684 sounds like… an omni mic, so it’s not a valid comparison to a 57, but it does sound pretty decent as an omni.  Might make a good under-snare microphone.

All of these forgotten Altecs are available cheaply on eBay from time to time.  I’ve never come across one at a flea market or swap meet, though, so I don’t think they are very common.  From what I can tell from my limited sample-pool, the ‘A’ designation after the model-number indicates that the mic uses an XLR5 (rather than the current standard XLR3) connector.  If you get one of these ‘A’ designated mics, you will need to find an XLR 5 female jack.  Wire an adapter to XLR 3 as follows: (XLR5:XLR3) 1:1, 2:3, 4:2.   The ‘B’ designated mics seem to have our current-standard XLR3 jacks.  Again, I am not 100% about this distinction, so check closely before buying if you don’t wanna be soldering adapters.

Helping you come to terms with the possibility of imminent demise

Download the 1965 and 1968 Altec ‘Airport Sound Systems’ brochures:

DOWNLOAD 1965:Altec_Jet_age_sound_systems_1965

DOWNLOAD 1968: Altec_airport_sound_systems_196X

What purpose can programmed sound serve in our environment?  Communication of information.  Entertainment.  Marking boundaries of different spaces.  All of this happens in the environment of an airport.  We need to know if there has been a gate-change for our flight.  We enjoy some sort of distraction or amusement while we wait.  We expect one sort of sound in the airport bar, and another at the gate.  OK.  So…  inform, entertain, delineate.  But how about… changing the mental state of an unsuspecting listener by lulling them into an acceptance of their relative insignificance in the universe in order to help assuage their fears of possible imminent death?

(web source)

Here’s how Brian Eno, composer of ‘Music for airports,’ widely considered to be the first ‘ambient music’ album, explains his project:

“… Whenever you go into an airport or an airplane, they always play this very happy music, which is sort of saying: ‘You’re not going to die, there’s not going to be an accident, don’t worry!’ And, I thought, that was really the wrong way around, I thought that it would be much better to have music that said: ‘Well, if you die, it doesn’t really matter.’ You know. So I wanted to create a different feeling, that you were sort of suspended in the Universe and your life or death wasn’t so important. …” (source)

Talk about turning the problem on-its-head.  I should say at this point that I am an unabashed huge fan of Brian Eno; IMO, there is no one person in the history of recorded sound that has been as able to imagine and exercise new potentials for audio.  Anyhow…  if you feel that his statements in the interview above seem somewhat grandiose/flakey/pie-in-the-(or falling from the)-sky-ish, I offer this personal anecdote.  I recently played the opening of  ‘music for airports’ for my students in my Soundtrack class (‘The Soundtrack’ is a course I’ve been teaching at the University which gives visual arts and communications students an understanding of the creative potentials of audio in their work).   We were discussing the programming of audio in public spaces – shops, restaurants, etc.  I played 5:00 of “Music for Airports” and asked what they music made them think of.  Several immediately responded, ‘death.’ OK, I replied…  how do you feel about this death?’  “Okay” was the reply.  Well done Eno.

It’s kind of hard to believe that there were so many airports in the US in the late 1960s that Altec published these 6pp and 8pp catalogs.   While there are no claims in these publications that these Altec systems might be used to effectively assuage customers’ fear of death, they do offer the following:

Lack of reliability (in an airport sound system) can cause not only inconvenience but actual danger and panic in some cases.  This is why Altec Lansing, pioneer in integrated sound systems, has stressed aerospace-level reliability in every… component.”

Altec stresses here that lack of reliability, such as it might result in the mis-cue of important verbal flight information, can potentially cause danger and panic.   Eno took this one step further by understanding that the music-programming of the environment can also have a dramatic effect on the mental state of the customers; and he systematically set out to design sound-pieces that maximize the potential of the sound-system to comfort those customers.

Products discussed include the Altec 650, 687, and 695 microphones; various compressors and power amps; and audio-signal distribution equipment. ‘Case studies’ which catalog various successful Altec airport sound-systems already in use are provided as well.


Takin’ em to Church (with Altec)

Download the eight-page 1966 brochure “Altec Sound Systems for Houses of Worship”:

DOWNLOAD: Altec_Worship_1966

The text above is taken from page 2 of this royal-purple-colored document.  The logical inference would be “As You Are To God, Your PA System Can Be To You! (with ALTEC)”

Been thinking about the voice/sound of God lately.  Our recent purchase of a massive Hammond Organ/Leslie speaker system at Gold Coast Recorders has led me to consider the features/tones/visual considerations that Hammond’s designers implemented when they designed these incredibly complex electro-acoustical devices.   The large Hammond Organs of the 1950s were designed (and commercially successfully, I might add) to replace the pipe organs which had functioned as a sonic {analog/representation/index/or-what-have-you} for religious expression in the Christian church for hundreds of years.  Notice that I say sonic  representation, as opposed to musical representation.  We experience the Hammond Organ/Leslie system as being impressive and one-could-say ‘godlike’ in it’s sonic attributes, even aside from any particular piece of music that’s performed on it.  The unusually deep, pure bass tones of the footpedals; the cavernous Hammond spring reverb system; the swells of the footpedal; the visceral emotional response that the Leslie speaker creates by way of it’s manipulation of the Doppler effect.

Sound systems in churches face certain special design requirements; this 1966 brochure from Altec addresses some of these concerns.  Low distortion, extremely high speech intelligibility, uniform coverage, and minimal visual presence; and all of this must be accomplished at a moderate overall acoustical volume.  Combine these sonic requirements with the fact that the sound system will often be operated by church members, ie., volunteers, ie., not-professional engineers, and you will find that operational simplicity is also necessary.

Given the large number of old Altec mixers on eBay with a stated provenance of ‘from an old church,’ I feel like Altec was probably pretty successful in their church-marketing initiatives of the 1960s.  From what I can gather, Peavey seems to be a leader in church audio today.  It’s interesting to examine the various products in their Sanctuary Series and note the differences between these and their standard nightclub PA line.

To my readers out there:  do any of you operate sound systems in churches?  Are there any special techniques in mic’ing, mixing, or processing of audio in the church environment?  Does anyone attend a church that is still using old green Altec PA kit of the 60’s?

Altec 438A – Modified for modern music production use

As we discussed in previous posts, the Altec 438A is an audio compressor designed in the late 1950s primarily for use in public-address sound systems.  It has a microphone pre-amp built in, and an absolute minimum of controls:  one knob determines the level of the signal that hits the input of the compressor; turn this knob all the way down and you hear silence; turn it high enough and you get a highly-amplified version of the input signal; keep turning it up and you get a highly amplified signal with the peaks attenuated or ‘compressed.’  There is also a 2nd input with slightly less gain; this unbalanced 100k ohm nominal input shares the same volume pot as the mic preamp.  I suppose that the 438A was useful enough in its day, as there are hundreds still to be found; but for use in a modern music-production environment, it’s pretty useless.  The levels are all wrong, there is not enough control of the compression parameters, and there is no proper balanced line-level input.

Here is how I took an original-spec 438A and modify it so that one could use it alongside more modern compressors in a music-production studio.

(From Left to Right): A switch to determine if either the two-stage mic preamp OR a balanced 15K nominal signal hits the input transformer of the compression amp; a threshold/ratio combo control ala the later Altec 436C; (top) an balanced output level control/pad ala the Gates Sta-Level (see here for details); (bottom) a release time control ala the Altec 436C.  The original volume pot still functions as an interstage gain control for the mic preamp.

Here’s the unit with the face flipped down, revealing the wiring to the newly added pots and switches.  At my client’s request I used 11-position detented pots; ALPHA makes these in a huge range of values and Mouser stocks them for just about $2 a piece.  A great value IMO.  I used sliver-plated 24ga stranded wire for the audio wiring and 22ga solid copper for the control signal wiring.

This 438A is now ready for use in any situation where a gentle, vintage compression sound is desired.  The input and output levels are what you would expect from a standard pro-audio compressor; the release timing is widely variable (but never very fast – this would cause some artifacts due to the way these simple vari-mu compressors function); and the threshold/ratio control will yield a wide range of results as well.  Since the unit was in good physical and electrical shape, no re-tubing or re-capping was necessary.