Bi-amping ADS L-1590 or L-1290

I have looked around everywhere trying to find out how to bi-amp the ADS L-1590's without having to use the impossible to find PA1 amps. Has anyone done this with an external crossover?
Abruceaudino, I have a pair of 1590's and had them biamped using an inexpensive rane crossover set at 350 hz.
Behind the low frequency connectors, move the switch to the left, for biamp operation. For what it's worth, I have a pair of pa1 amps. They do sound real good, but they are 25 year old technology and small. The speakers sound better with better amplification.
I have a spare pair of 1290s. I have bi-wired and bi-amped them without an external crossover. I used the internal bi-amp switch and I thought they sounded great. Maybe they could sound better with an external crossover but I never felt the need to try one. Even though I have the 1290s as a spare set, I will probably never get rid of these speakers. I would maybe trade them in for a nice pair of 1590s.
I may try bi-amping w/out the crossover just for the heck of it until I can pick up an external one. However, dont you risk damaging the speakers or at least ruining the sound by sending the full frequency to all the speakers? From what I gather, selecting the bi-amp switch in the back disables the internal crossover, which is why you need an external one to properly bi-amp them.
ADS actually made an electronic crossover for the 1230/1530/2030, called the C2000 Biamp Control. As per an ADS bulletin, it can also be modified quite easily to work with the 1290/1590. I have owned several of them over the years, as I own a pair of 1530's and 1590's. The main difference I noticed in biamping was additional bass output, and not much else. I now use Velodyne 1500R subs with each pair, and find this preferable to the added expense of an extra amp and cabling. Occasionally a C2000 will appear here on the 'Gon and on Ebay. If you should consider this, and want to know how to make the mods to work with your speaker, I have the info on how to do it.

There is also an electronic crossover that Bryston makes that could also work quite well. It has adjustable crossover points and should match up well.

A real must-do, tho, is to make sure you use identical amps-it will make balancing everything a much easier task. I also tried a pair of PA-1's, and wasn't impressed at all with them. The bass wasn't that great, and power seemed to be limited if you like to play them loud.

And last of all, good luck! You have a great speaker!!!
If you go without the crossover, the biamp switch gives you direct woofer input, but the midrange and tweeter are still protected by the crossover.
I had tried mine biwired, and the woofer does play some of the highs,sounding a little bright for me.
Mine are not being used at the moment either, but I have had them since '85, and when i hook them up they still sound great.( Still have the owners manual. for crossover info etc.)
Thanks for all the imput. I may experiment down the road when I replace my integrated amp with a seperate pre and amp as I cannot hook an external crossover network to that as of now. They are great sounding speakers nonetheless and mighty enough on their own without the bi-amp for my room for now.
I have had my L1290's bi-amped for the past two years. I'm using a Marchand active crossover upstream of a pair of Adcom 555's. It makes a big difference in soundstage and clarity, probably mostly due to allowing the amps to focus on a narrower band of frequencies. If you haven't noticed, these speakers love power. The more the better.

Interesting comments. My L1290/2 speakers were hooked into a Rotel RMB-1066, switched for bi-amp mode, wired appropriately and I wasn't happy. On first try, it sounded pretty clean and had good low range depth but after loading up some CCR (Suzie Q) I noticed garbled output where Johns guitar seemed to dissappear on some notes. I pulled off the double cables (for amp A and amp C) and went with a single amp using the internal cross-over. Clearner but less depth of field. Currently looking for solutions to get the most of the ADS....a great little speaker
I have recently acquired a pair of L1290/2 speakers and was wondering about biamping myself. My only reservation is that I can't find anything anywhere about the proper frequency to set an external low-pass crossover. I would think a/d/s would have included this info in their owner's manual for the 1290/2's but no such luck. Anyone have any ideas? Thanks
I just found myself a pair of ADS L-1590/2 with the org boxes in mint condition.
I have an 300 wpc mcintosh power amp. My question is can they be bi-wired?
Each speaker has 4 post 2 are ued for bi-amping. i know there are two switches on the bottom one for turning of the tweeter but what about the other?
Ooops I was wrong- the L1290s' woofers are crossed over at 500Hz and below, the L1590s' woofers are crossed over at 350Hz and below (even though both speaks use the same midrange.) ADS did provide this info in the manual- I just didn't look hard enough.
Jhorsh- you cannot biwire these ADS models the way you can biwire a typical speaker with 2 sets of terminals today. Biamping is the only possibility because of the internal crossover circuitry configuration, and to do this you must have some sort of external crossover mechanism (I'll get to that in a sec.)
The right hand set of speaker terminals on the back of your 1590s are for complete full-range driving of the speakers. If you are running each speaker full range off one amp or receiver channel, you connect the speaker wires to this set of terminals only, and the biamp switch (the bottom switch on the back panel) is set to the right for full range operation. However, if you choose to biamp, you set this switch to the left, and connect the low frequency speaker cable to the left set of terminals and the mid/high frequency to the right set. BUT (and here's the problem)- setting that biamp switch to the left deactivates the internal low-pass crossover for the woofers. (The tweeter and mid are still protected by the internal mid and high pass crossovers, so you can run them full range off any amp, but the low frequency signal MUST be crossed over externally somehow.) If you try to biamp or biwire without an external crossover somewhere, you'll end up running the woofers full range, which will not only sound wrong but may damage the drivers.
Back when they made these speakers, ADS also made an optional complementary amp/crossover component called the PA1, that was specifically designed to fit in the back cavity of the 1290 and 1590 speakers (This is what the first post was referring to) that allowed biamping. They also put out an external crossover unit called the C2000 that you could use in conjunction with your own amps. But both these units were only made for a couple of years and are extremely hard to find- so the only option for most of us to get the most out of these speakers is to use external amps and crossovers. If you choose to try this, you shouldn't have too much trouble finding a suitable amp with a low pass crossover setting of 350Hz (where your 1590 woofers are crossed over) but I'm having a heck of a time finding one that will allow a 500Hz crossover point for my 1290s!
To be honest, driving those 1590s full range off that Mac would probably give you about the fullest potential the speakers have to offer!
Sblagg you can build or buy a line level passive crossover which you would place between the pre and the power amp. I believe you'll want a second order for that ADS. There are a few sites that will give you the formula to build them. Which in turn allows you to use better quality components. Car audio guys use Fmod's which will work also if you aren't a DIY type.

Either way should work well for you. were correct on not biwiring, it sounded like crap and found a few sites on damaging to the speakers. Single wiring sounds the best. I was thinking of just adding a small sub to my system i think it may help.
i was going to upgrade my speakers but most of the speakers are described as smooth and warm sounding. My music taste is stones to Van Halen.

Thanks Ausjoe, I actually found an active crossover that looks to be perfect to use with these, it is the TDM 24CX-2, 2-way with a 24 db/octave Linkwitz-Riley slope. Has crossover settings all the way up to 750Hz with an exact 500Hz setting so should be ideal.

Jhorsh, the early-mid 80s ADS towers are often classified as a great speaker to listen to rock music through because of a lack of subtlety or politeness, but IMO they can still sound great, smooth and detailed, with all types of music. I think the "in your face" classification these get stems more from their ability to be driven hard (they do require decent power to sound their best) and play at ridiculously loud listening levels with no distortion, than a true sound characteristic of the speaker itself. (I tend to view speakers such as Cerwin-Vegas and the larger Klipsch Heritage models as more of typical "rock" speakers-- those just weren't made to be subtle.) It has also been my experience that vocals can sound just a bit repressed through these speakers if you have them too far apart or tight against walls, but if you have them situated in your room correctly and are right in the middle of the soundstage you can achieve fine detailed sound through the entire audio spectrum.
Can I use an ADS C2000 bi-amplifier system controller with ADS L1590/2's. or does it need to be modified?
Well i can't find a ADS crossover or pa1. Should i sell them and give up.
what i'm worried about is what to replace them with. how much do i have to spend. does anyone have a crossover so i can get more base. are they worth keeping? whats better than them under 2000...need help soon.
I have a pair of PA-1's that need some repair. Does anyone know any vintage repair shops that would have experience with the PA 1's? These puppies were hard to find I want to get them repaired correctly.
Try Richard So in Arizona, He should be able to help you, as he deals in a lot of stuff for a/d/s and repairs speakers.
Jhorsh, if you need info on biamping the 1290's or 1590's, I can help you. Contact me at:
Alan (sid42)
Mkaz13, do you have the manual for the PA-1? I need to locate one, or a copy of it.