Audio Pulse Model One

Coastsider

Curmudgeon
Another of my finds in this weekends Audiokarma induced search of the high shelves in my garage was an Audio Pulse Model One Digital Time Delay System. Not much to say about this except that I must have thought I needed one at the time. Since the year of purchase escapes me - although it was probably sometime in the 70's - does anyone have any information on this oddity?
 

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I'm afraid that I can't help much with information about your delay unit, but if my memory serves me those units were just about the frist digital delay units on the market. It seems to me that was in the early '80s. I looked into buying one of those when they were brand new on the market.

I had a very good friend, now deceased, who had an ADS analog delay component integrated into his modest system and it was truly an impressive sounding system. The core of his system was a Sansui integrated amp and his ADS delay system. I think the ADS had its own amplifer because I don't remember any other amplifier in the system. He was driving a pair of Marantz Imperial 7s and a second smaller pair of two-way speakers as the delay speakers. His two-way might have been Advent's but I don't recall. His sources were two turntables, three 10" reel-to-reel recorders, and two cassette recorders. No tuner or CD. He had a huge vinyl and tape collection that he used regularly, so he just wasn't interested in FM or CD.

After hearing his system and being very impressed with it, I looked at adding a delay system to mine but never did. I still think about how good that system sounded and as a result currently have a Yamaha DSP-1 delay unit, that I scored off ebay some time ago, stored. I am planning on eventually integrating it into the vintage surround system installed in my garage/shop. In hindsight, what I think really made Dave's system sound so good was that he had gone to great pains to do a beautiful and optimized installation in his family room and that really allowed the quality of the components and music to shine. Pleasant memories....
 
I was all about paying for R & D back then so I was usually the first one on my block to have something new.

I've been racking my brain about this Audio Pulse and seem to recall that the owners manual was a bunch of xeroxed hand typed pages stapled together but have no idea where it might be. I also recall that I used it in conjunction with a Phase Linear 400 driving two Infinity Monitor speakers for the rears, and had a Phase Linear 700 driving two Infinity Monitor IIa's in the front. The Monitor IIa's are still in service as front left and right speakers in my current 5.1 system.

The search of my garage will continue and I will post any new finds in the appropriate forums.
 
A few companies made these delays. Really neat stuff!

I had a nikko unit until recerntly, and two of the a/d/s/ units. The a/d/s/ units came as either non-amplified, or amplified, with a heavy beast of a quality amplifier built into the unit.

These are used to make a room sound "bigger". Some of the settings on these are "Concert Hall", "Large Room", "Club", ect.
 
thedelihaus. That amplified ADS unit that you mentioned is the unit my friend Dave had in his system. That was one good sounding system too! We listened to a lot great music on it too. We listened to alot of vinyl on his new Yamaha PX-3 linear tracker, what a great turntable that was, and alot of reel-to-reel tapes! All good stuff!

I really liked the sound of those delay systems too. When I was considering adding one to my system the ADS units were no longer available and the Audio Pulse units were the big boy on the market. I seriously considered buying one, but the fact they were unamplified and I would have had to buy additional amplifiers broke the bank, so I had to pass. Later on I looked at the Yamaha DSP-1 when it first came out but it was big, big bucks at the time, so I looked at a really nice Sony unit, and even bought and tried out a Koss unit. Unfortunately the Koss unit just wasn't a good match for my system so I returned it and by that time the Sony had whizzed through the marketplace never to be seen again, so I was just out of luck.

I never forgot how good those delay systems sounded when they were setup properly, but when the Dolby surround sound for movies came out, all the new delay products included surround sound settings for use with video and eliminated a lot of the music delay settings as a result. So that, combined with some extensive field assignments at work that kept me on the road for extended periods of time, caused me to lose interest.

However, a couple of years ago I saw a Yamaha DSP-1 on ebay and grabbed it for the princely sum of $75. The guy selling it even threw in a Sony Dolby Surround Sound unit that he used with the DSP-1. Both pieces were/are like brand new. That gear is currently stored and waiting to go in service in my garage/shop system. So eventually I'll get my delay system up and running.

Judging by the overwhelming interest shown in this thread so far, by the rest of the AK world, I would venture to say the you (thedelihaus), Coastsider, and me are apparently the only people still interested in them. Oh well, I'm still listening to LPs too.
 
Another of my finds in this weekends Audiokarma induced search of the high shelves in my garage was an Audio Pulse Model One Digital Time Delay System. Not much to say about this except that I must have thought I needed one at the time. Since the year of purchase escapes me - although it was probably sometime in the 70's - does anyone have any information on this oddity?

Yes. I have the Audio Pulse Model One Digital Time-Delay System. It was purchased new I believe in 1977 for over $700. The manual is very informative and well printed and is spiral bound. The effect on the sound in the room is very live sounding. One feature it has is the ability to make Mono recordings have a Stereo quality about them. Audio Pulse uses ninety separate shift register IC's to provide delays of 8, 12, 22, 36, 58, and 94 milliseconds of discrete delay.
Reverberation decay time: variable from 0.2 to 1.2 seconds, and those times are measured as the time for the reverb output to fall by 60 db after a transient. The introduction of the Sony Beta and the JVC home video tape recorders caused a lot of extra audio equipment to be shelved and forgotten .
 
Yes. I have the Audio Pulse Model One Digital Time-Delay System. It was purchased new I believe in 1977 for over $700. The manual is very informative and well printed and is spiral bound. The effect on the sound in the room is very live sounding. One feature it has is the ability to make Mono recordings have a Stereo quality about them. Audio Pulse uses ninety separate shift register IC's to provide delays of 8, 12, 22, 36, 58, and 94 milliseconds of discrete delay.
Reverberation decay time: variable from 0.2 to 1.2 seconds, and those times are measured as the time for the reverb output to fall by 60 db after a transient. The introduction of the Sony Beta and the JVC home video tape recorders caused a lot of extra audio equipment to be shelved and forgotten .

All of that is sounding very familiar - the price, how it sounded, and the multitude of available settings. Perhaps my memory of the hand typed nature of the manual is incorrect because your mention of it being spiral bound sounds familiar. I have to have it somewhere since I kept the unit, so I may have to spend some time today looking in more garage stored boxes.

Attached is a scan of a small card that was taped to the top of the unit and is apparently a handy reference I made up for the various decay/delay settings.
 

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Time delay systems never really caught on back in the 70/80s. Probably a combination of perceived audio gimickry and the recent failure of quad. Digital signal processing (actually quasi-digital delay lines) was in its infancy when the Koss & other reverb units were on the shelves so the effects were quite primitive compared to even the cheap DSPs on BPC AV receivers of five years ago.

A neat toy in its day but nothing special these days IMHO.
 
Audio Pulse Model One Manual

I orginally purchased my 1st Audio Pulse One from Jack Hienes who owned Sights and Sounds out of Chicago Hieghts IL. About 1976 I think. I am still using it. I have purchase 2 others including a Audio Pulse Two, which did not require a second amplifier.

I still have my orginal manual, insert sheet and ad or product sheet.

I am in the process of scanning and turning this into a PDF format with bookmarks. I have included my e-mail address if you would like a copy.
larrdunn@sbcglobal.net
 
I remember hearing an Audio Pulse set up year's ago at an audio show and knew I had to have one. The price kept me out for awhile, but ended up with a ADS model 10 unamplified job, since I already had another amp and speaker's. This thing really opened up my small room, but at higher sound level's, the early digital bit rate's didn't handle sibilance very well. Was pretty cool for headphone listening. Been using a more modern Yamaha 1000 unit for awhile now in moderation, and seem's to fill the bill.
 
Audio Pulse was also a Canadian speaker company back in the early 80s' that went on to make make Energy, Mirage, Sound Dynamics and Paisley. I wonder if it's the same gang?
 
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I had a Model One. Right after I bought it (used), it smoked all those shift register ICs. So I was told by an Audio Pulse repair specialist I sent it to who advertised in the back of Audio Magazine, they had a ground problem with the +/- power supply and could fry the ICs. I recall spending about $300 to get it repaired after paying about that much for it. Ended up selling it years later with that spiral bound manual and original box for $25 (starting bid) to a sole bidder on ebay. Got screwed all the way around on that! Fortunately the buyer was local and I didn't have to ship it. I never really cared for the effects it produced.
 
I surfed here because I saw one of these on Ebay when I was looking for a broadcast delay for a radio station, but from reading your comments I gather this is not that type of delay. I need one that is a profanity filter delay with a dump button. I am looking to help a new grassroots, shoestring radio station setting up so if anyone can help, let me know.
 
This forum really isn't for broadcast radio equipment. Try posting in the off-topic forum.

I thought most radio stations have switched over to PC based audio systems.
 
I used to work in a shop in the 70's that sold the Audio Pulse One.

One thing I remember. The salesmen were in the listening room experimenting with this revolutionary concept for its day... One guy stated that he was told by Audio Pulse that the best rear speakers would be cheap boxes (with a good size woofer.)..that the speaker did not have to be audiophile quality. And, was told to disconnect the tweeter. For the rear reflections in a hall lacks much high end. I believe he also said that they recommended the speakers be facing upward behind you. I can recall noticing in my high school auditorium during concerts that the sound bouncing off the walls behind me was not containing high frequency sounds..
 
The Audio Pulse One I had sounded very artificial. I suppose placing the speakers pointing toward the ceiling and disconnecting the tweeters could help mask the lousy effect the "Pulse" produced. Sad thing was, the $45 Sound Blaster card in my old Windows 98 machine made superior reverberation effects. Including the higher frequencies.
 
I bought one new in the late 70's early eighties. I was depressed as I just sold my Corvette . One of the biggest mistake purchases I ever made. After a year or so it started smoking. I still have it in the original box.
 
I had an audio pulse back in the mid 70s and paid around 7 hundred for it. I remember if it was set up for the music you were listening to it could be very convincing. The trouble was you were adding distortion to the music which if it were a live performance there would be some distortion. If you had it set for classical music and then switched to a vocal piece it sounded like they were singing in a tunnel. You pretty much had to reset it every time you listened to something. At some point it just became a pain to use.
 
I worked for Hybrid Systems there on Crosby Drive in Bedford MA (very near Burlington and just off Rte. 3 near Mitre) in the summer of 1976. Their main business was ADCs and DACs for avionics, and Audio Pulse was a subsidiary. I did electronic tests on both the Audio Pulse Model 1 and Model 2.

The Model 1 had individual shift registers in a sequence that seemed to challenge the clock circuit. I would inject a test signal into the delay board and see if it made it to the end of the chain. When it didn't, I would work backwards to find the offending register and replace it. Often, another register would then stop working, so I would replace it. Eventually I would get to a complete set of compatible/working registers and would send the board on to assembly. Must admit that I got p-r-e-t-t-y good at unsoldering 16 pin TO cans from double-sided boards. I also drew a line across some good and bad registers using black and red sharpies/magic-markers to identify (in case anyone has happened to look inside a Model 1).

The Model 2 used DIPs and seemed to be a much better design (as well as including the output amplifier). Testing the boards was more involved, but there were fewer failures. I won't mention zapping my little finger a few times ...
 
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I bought an Audio Pulse model 2 at a garage sale for $20. It was only about 2 years old! I used it from about 1980 or so until 2000, when it began to do some odd sounding things. I was planning on seeing if it could be fixed, there was someone who worked on them someplace. If you kept the settings on the conservative side, it sounded great.

Sadly, my basement flooded and the AP was on the floor. In the 35 years I lived in that house, I had water in the basement one time. It wrecked 4 old speakers, the AP unit, and a really nice Sony ES CD player that a friend gave me in trade for some parts I had for a gun.
 
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