Power requirement for ADS L-1290?

Here's my weird question of the day:

I got a set of hand-me-down ADS L-1290s...(I know, I know, quite a nice gift. It's true. I'm very fortunate).

Everyone says they love power, saying things like 'the more power you give them, the more they sing,' and other nice but imprecise stuff like that.

They're rated at 300 watts maximum, and they're not terribly efficient; coming in at 90db at 8 ohms. Exactly how big does my amp need to be to get "decent enough" sound out of them? I fully realize that the very notion of "decent enough" is anathema around here, but I'm not wealthy, by any means, and look to the vintage audio market for my stuff.

Would 65 wpc be enough to get them to sound good enough? 80 wpc? 100?
If you have an amp that is within the range who've brought up, they should play fine.
I'm using a Yamaha DSP-AI Integrated Amp(100 wpc)with mine, and that's plenty of power. I've used them with my McIntosh 7200 Amp (200 wpc) and it's interesting to note that the meters never register over 20 wpc. You have good speakers!
I had the slightly smaller L-1090. I got by with 60 wpc for awhile, but when I fed 'em a high current 200 wpc amp they really came alive. They're not 90 dB efficient, not even in-room. They're more like 86. How much power you need partially depends on the room size, and current delivery is *at least* as important as final wattage. I strongly suggest a minimum *high current* 150 wpc. Even better would be to biamp at 150 to 200 for the woofers and 100-150 for the mid/tweet.

And get some outriggers and spikes for them as well. Back when I had mine I was able to get a pair of pedestals that ADS made for them. Then I set some spikes into them as well. Since those pedestals are pretty scarce these days and the L1290s are tall with a small footprint, the outriggers are a good idea to stabilize the setting of the speaker.
I owned a pair of these for quite a while and liked them. I had a stash of new/old replacement drivers just in case espcially since the fluid in the tweeter can go bad with time.

To answer your question, they do like power, and bi-wiring if possbile, but also an amp capable of driving low impedances/ohms.

I used a Rotel RB-1090 with them and then a Spectron MKII all of which exceeded the power max recommendations and both sounded good with the better sonics going to the Spectron.

They will 'play' with less power etc but not up to the capabilities of the speaker and low power inexpensive amp may not be able to handle the low impedences and thereby produce clipping.
I am running these with a McIntosh MC-275 amp and they seem to do fine. DO NOT BIWIRE these speakers. They can only be actively bi-amped (with an external crossover). The bi-amp switch in the back disables the crossover network between the woofers and the mids/highs. The passive network will remain intact on the mid/high. If you try and bi-wire, you will be sending the full frequency to the woofers and it will not sound good. The passive protection remains on the mids. If you want to attempt to bi-amp, you need to get an electronic crossover (DBX, Rane, Bryston, Marchand, etc.) and set the slope to 12db/octave. The highpass and lowpass cutoff is 350hz. The results will be some better bass extension. I didnt care for it to be honest. The extra noise of adding a crossover between my pre-amp and amp wasnt worth the bass upgrade. They are powerful enough as is.


What improvements were brought about with the spikes? I have been thinking about adding these as mine are just sitting on the floor.

90db @ 8ohms is actually quite efficient. But I agree that they would do better with at least 100wpc or more. I dont know about the impedance dips as I have never seen them measured. Perhaps someone else can comment.
I can answer this pretty well since I have the same speakers and I started out powering them with a 60 wpc Denon receiver. They were OK, but then I purchased a separate Denon Power Amp POA-5200 (125 wpc) and the sound difference was very significant. Much deeper and richer bass and mids. Much more dynamic in terms of the clarity and volume of different instruments in the music. I think you'd be much better off with more power for those great speakers.
A pair of the L-1290/2 speakers were just given to me and they are in good shape. The oak cabinets are in excellent shape, but one midrange was pushed in and has what looks like shag carpet fibers on it. Perhaps it had fallen down on some carpet. I wasn't able to remove the midrange metal piece from the cabinet to try and push it out from behind, but was able to restore most of the shape of the dome by pulling with some masking tape.

I have a pair of DCM QED 1A speakers that I bought in 1985 driven by a Denon AVR-1910 receiver (90 watt x 7). My QEDs are not terribly efficient, being transmission-line technology, perhaps 86-88 db SPL, but the sound quality and dispersion continues to impress me even after shopping for a second room modern bookshelf/sub setup last year. The L-1290s are almost the same vintage as my QEDs, but cost 50% more back in the day. I was thinking of using these as rear surround speakers, but a Stereo Review of them from 1984 measured them as 4 ohm and 90 db SPL. I worry that my receiver will be able to drive them with their low impedance along with my QEDs and volume matching them since they are more efficient. I'll have to go through my receiver settings and hopefully I can adjust the rear volume separately.
I swapped cables with my QEDs and they sound awesome even with the slightly deformed midrange and the tweeter above also had some fibers on it. I listened to my favorite reference CD, Dire Straights - Brothers & Arms 1985, mostly track #4 Your Latest Trick. There is more detail and clarity than my QEDs - I can separate the symbols from the other high frequency sound which blends in and is less transient on my QEDs. The saxaphone can get a bit tiresome harsh at reference levels on my QEDs, but not the slightest on the ADS. The bass is also fuller and contributes to a larger overall stage presence. These speakers impressed me enough that I decided to replace my QEDs with them as my mains and I've ordered 50 foot 12 gauge cables to hook up my QEDs as surrounds. They are pretty closely volume matched to my QEDs so I think the SPL db is close even if they are lower impedance. My receiver does have separate volume levels for each speaker.
I've had a pair for years
Originally with mono blocked NAD 2155's ( 125 wpc )
Then Emotiva UPA-1's ( 200 wpc )
This week I changed to high current Emotiva XPA-1's ( 500 wpc )
Each increase in power made a pretty startling inprovement
Br56's experience matches mine. The L1290s may have tested at 90dB in-room at 1w input (there's about a 3dB boost from room reflections on average), but these sealed-box speakers can use all the power, current, and damping factor you can come up with. I had the L-1090s as I mentioned 11 mos. ago in this thread. Going from a 60/90 wpc (relatively) high current receiver to a true 55-lb. high current 200 wpc power amp was like, "Whoa! No way is this amp leaving the house!" It seemed to add 1/2 octave of bass extension, plus increased clarity, speed, and dynamics, plus a more liquid sounding presentation. It wasn't just powerful, it was simply better in every way--natural-sounding mids and highs like a tube amp while maintaining that SS-style tight grip on the bottom end.

Anyway, it doesn't surprise me that 500wpc would open such a speaker up even more.
I've owned a pair of L-1090/1 speakers since new and have always enjoyed them. I picked up a pair of L1290/2 speakers recently and have been enjoying the extended bass of the larger LF drivers. Similar sound to the L1090s but much fuller sounding. They do seem to like my rebuilt Yamaha M-2 amp at 200+ WPC.
Now after all the raves about the 1290's, try out the 1590'2's. Now there's an awesome speaker! I own them both and will never part with them. Even better, the 1530's, although huge in size comparison, put out the best sound of any of them. I only sold mine as I am retired now and had to downsize for a smaller home. ADS was great in their day, and still are!
Nice speaker! With mine I've used 1) a 25 watt HK430 receiver; 2) a 100 watt Outlaw RR2150 receiver; and 3) a 100 watt pure class A, high current boutique amp. They sounded 1) ok; 2) really good; 3)damned near great, respectively. Bottom line: the more power and higher quality you feed them, the better they'll sound.
I am considering a pair...would a single NAD 2600 (recently recapped etc, rated at 150 per channel) be able to reproduce the bass response folks are describing? How would it handle the low impedance characteristics? or would my efforts tracking down a second 2600 ( 2700, 2400) and set 'em up mono for each channel be worth while? based on the thread, it certainly sounds like More Is Better!

Thanks for the feedback.
Don't know the amp offhand but from your description it should be fine. I also ran a pair of ADS L-880 with a 45-watt NAD receiver for a few years in the '80s and they sounded very good, especially in the bass.
Thanks WRM57, I have my eyes on a pair of the L1290s we'll see if I can land them... If I do, I'll report back with some experiences.
So, I did buy a beautiful set of L1290s, original series, w/ dual fuses, removable back plates, bi-wireable, etc. they are Sweet! The NAD seems to be functioning beautifully as well, which is a relief.

Happy Listener over here!