Anyone remember an ADS delay unit for running rear speakers with 2 channel stereo?

[dan-c]

I remember them pretty well too. Properly set up it sounded way better than Quad. I guess it kind of killer quadraphonic sound

 

[sqlsavior]

I thought the ADS unit sounded pretty darn good, and did what it was said to do. It had the ability to roll off the highs on the rears, as I recall. It came out just as equalizers were being touted as 'the next thing you need', but the delay effects were a LOT more subtle than equalizer effects. Only one customer listened to it carefully, and seemed to like it, but not enough to buy it...

 

[CT Jim]

I bought one of the Dynaco units Wayne mentioned from a fellow AKer a few months back, but I haven't hooked it up yet, just placed it on top of my stack of Dynaco stuff for looks....

 

[BinaryMike]

The CMOS shift registers would fail easily. For a while, ADS sold TTL replacements, but those use considerably more power and replacing a few shift registers would then overload the regulator for the logic.

It's possible that 74HC/HCT series devices would drop right in and consume far less power than standard 74 series TTL.

 

[jdurbin1]

The ones I had sounded ok and I agree the effects were fairly subtle/reasonably musical, but the s/n ratio wasn't stellar for sure - lots of hiss. Might not have been 100% functional but getting it quiet would have been a real uphill battle. No service lit for one thing.

John

 

[Pimpsta763]

I have one that I got for free from a friend. The digital delay does not work, the amp still works. Thanks

 

[musichal]

Played with one when I sold ADS speakers. Thought it sounded horrible. Even properly adjusted. Rear channel ambience got a lot better a bit later. I wouldn't pay $5 for a used working model myself. Ear of the beholder.

 

[Rockon1]

Hmm I could try it with one of my FX processors. Already have the second pre-out on my Caver running a second set of speakers for ambience (reflecting off the wall) Just have to insert the FX unit between the pre and the amp... Bob

 

[zinda]

After reading this thread and finding one of these in fully working order, I have to wonder just how accurate memories about a piece that most only heard once or twice some 40 years ago can be? I just connected it to DVD player that has a card reader and I didn't heard any hissing noises, although if the noise is over 15KHz I wouldn't hear it that much anyway. What I did notice by just using it as a regular 2 channel amp with effects turned off was that it stayed on when using some pretty low resistance speakers connected to it. I had just put some drivers in some modified tiny cabs and wanted to see if they were acceptable but had to connect another amp to run full range. Thought I'd kill 2 birds with 1 stone since I never tested the amp yet.

The thing I am curious about is exactly what the delay consists of? Meaning is it merely delaying as we now know a delay to be of is it removing some sound as it does so. I see there's a number of settings available but I can't find any manual or brochure that tells me exactly what it's doing. I have more amps available but it's not that easy for me to set up another multi amped system right now and thought I could save so e time and effort if I knew what it was actually going to do.

For what it's worth, I was considering the possibility of seeing how it would do to align separate drivers running on a multi amp system. Like delaying tweeters or mids sent from an active crossover?

It looks like any output can be input back into the amp section so it could play different roles depending on which outputs are used. With 2 separate delays available there very well could be one that might be short enough to be used for driver timing correction? As long as the signal isn't completely changed by the processor.

I'll report back if I get anything figured out, I have a few RTAs on hand right now that might be able to do tests without needing amps and speakers set up just to listen to it. I'll be able to see if the signal changes dramatically right out if the RCAs. I have a scope but it's been sitting for years and don't know if it works, I won't know the exact amount of time of delay without it.

 

[jdurbin1]

This article may answer some of your questions.

I can also email you the ADS consumer brochure that goes into some detail on how the processing is done, and the owner's manual (both too big to post here). You can send me your email via Conversations.

John

 

[zinda]

This article may answer some of your questions.

I can also email you the ADS consumer brochure that goes into some detail on how the processing is done, and the owner's manual (both too big to post here). You can send me your email via Conversations.

John

Well by the time I connected it up the 2nd time there was a problem! Argh! 1 channel is quiet depending on how the switches are set and how its encoded makes the output change volume greatly on one channel. Took a look inside and I instantly spotted a broken lead on a diode on the left side board that runs along the side in a verticle mount. Repaired it, then noticed the boards don't match left and right. One has obviously been replaced or repaired and capacitors are different manufactures and many are different values too. All the resistors are the same and diodes look the same but you know they are hard to see the actual numbers. In fact the one I replaced was nearly impossible to read the number, that's what made me look at the other board closely trying to find a match (I ended up using a very popular size and number with a 20 on it I have piles of them).
Fixing that diode made no difference! The amp section appears to still work fine when the jumpers are removed and the preamp is bypassed but it gets pretty warm after typical volume and normal use. It puts out about 1/10th of the power I'm used to running and it has found it's spot among a stack of other amps I'll never use, or several stacks of amps I'll never use.

I picked up a Behringer DCX2496 digital crossover (they call it a speaker management system) but it has the much needed DELAY available on all 6 outputs. This has allowed me to get my electrostats delayed to match the 2-8" low mids, while also allowing the 2x 8s to delay enough to match the single 12 on each side. The 8s are set at 12.xx milliseconds and the panels are delayed 4.xx miseconds more than the 8s so they're almost 17ms delayed from the 12s which are mounted on the side of each cabinet.

First day I had them finished and ready to test, initial run during mid afternoon last Saturday, just RTA'd them and found them to be running very close to flat (as flat as the mic can read, they claim 20-20KHz + or - 3db, I'm not that gullible, maybe 30 to 12KHz since that's where I see an immediate shelf drop of 6 db that never moves even though I can crank up the 16KHz setting and hear it getting way louder but never changes on RTA screen).

As I was saying, I didn't even have it cranked up loud at all, I was at about 8 o'clock on the dial and have my amps at 50% so I have some room to move the volume knob without being scared to touch it fearing it will be at concert levels if I bump it, and my nextdoor neighbor is pounding on my front door! I'm not sure how long he was there but between songs I could hear something. Actually thought I heard it at the break in last song but dismissed it. He's screaming at me to turn it down like I'm his kid or something! That's not the correct way to handle this, he saw me working on building the test cabinets all week long and had to know I was going to use them! So now I hate him and I'm sure his big deal is all about his dog freaking out from the subs I added and the new 550W RMS @4 ohms x2 amp powering them. Seriously, if he thinks that his yelling at me is the end of hearing my stereo, he's going to have some raw knuckles as far as I concerned he handled it way wrong being my neighbor, he knows I'm not going anywhere? He inherited his house after his mom died, she was very nice and the 60 something year old son that's been sponging off her since I bought my place 17 years ago has to have a roommate to be able to pay bills, and Homeowners fees, part time at Walmart, plus a 12pack a day habit probably barely covers it but at least his bicycle he rides is in good shape!

The time alignment has put the finishing touches on my system, I do have a 2nd set of DIY electrostats with 10" subs as well.
Test cabinets are heavily modified and ultra strengthened technics and Jensen towers. I'm starting on my own cab design now that it's cooled down in Phoenix. Going to start a thread for suggestions. I also have hundreds of other drivers I can use for subs and low mids.

 

[DEAFASABAT]

I run a 4 speaker, 2 channel system without any delay of any kind and it works very well, but you have to have the right kind of speakers and one of the amps needs a volume control (to balance it). My rear speakers are the JBL S109 Aquarius IV and the mains are the JBL Studio 530s. Its like listening to headphones, only with the air of speakers.

Dynaco/Dynakit had a quad-adaptor that required only an amplifier with all negative speaker output terminals connected together (commonly called "common ground"), and it sent out of phase material embedded in the music to the rear speakers. In an ideal set-up, all the speakers should be the same, but most do not have that arrangement on hand, so watch the impedance, and they should have the same efficiency rating (example: 90db/m/w). That device also requires a "common ground" type of amplifier (which almost all of them are).

Having used a Dynaco Quadaptor with four AR-5's and the AR Receiver, I knew that even if you had rear speakers with the same efficiency as the fronts, the rear levels were not always high enough for the best effect. This varied with the nature of recordings.
I was able to overcome the shortfall by connecting the (-) conductors of the rear speaker cables together, and placing a 15 ohm rheostat between that point and the (-) (common) output terminals on an Advent 300 receiver. The setting of the rheostat was adjusted for the desired amount of "ambience" and the Advent's output power would make up for the loss in rear level caused by the impedance of the rheostat. The 15-20 watt/ch. of the Advent was more than sufficient to balance the rear sound with that of the front speakers, which were powered by a 125 w/ch. @8 ohms power amplifier. Sort of a "Super Quadaptor". It worked very well.