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I have found 2 sets of Specta speakers for sale in the Anaheim area I would like to purchase but the women who owns them (husband has passed) doesn't know how to take off the interface and base for shipping. Anyone in the area who could possibly help? Compensation available. Please pm me if interested. Thanks!
 
Thanks for the helpful comments. Fortunately, I found a pair of Spectra 6600's for sale and bought them this morning! I will be flying out to get them- will take them apart and ship back.


Really excited!

Curious as to why the serial number is blank on these??? How do I tell which is left and which is right?

Thanks!



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On the top plates green or red holes with dots on mine I have also put the side designation by masking tape on each of the interfaces. Can also note a designation on the wood on the very bottom of each panel P.S. I will be having to downsize over the next year or two at which time they will be available for sale along with a model 1+1 pair and a single model 1. The interfaces for the 6600 have been updated with all new old stock circuit boards and transformers 2 years ago
 
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I'm excited about your acquisition of a pair of Spectra 6600! I would estimate only about 25 pairs were made.

I don't know why the serial numbers are blanked out - I'm quite sure it didn't leave the factory that way. My only thought...and it's not a good one, is that the speakers were stolen and the thief blanked out the SNs to avoid identification. Let's hope that's not the case! (And this makes one ponder how one would steal a pair of speakers that big...not impossible, but challenging!) I also note that the box below the serial number has also been blocked out - this field on the label indicates whether the transformers are wired for 4 panels or 6 panels. Also, what are the white squares on the top surface of the interface? And finally, the power-on indicator appears to be a green or blue LED with a bezel around it - Acoustat always used a red LED here, without the bezel. Perhaps this was part of the "recent service".

There are physical ways to tell left from right, but over time, the colored dots may have fallen off, or the top plates may have gotten reversed. The best way to tell is by listening. The high frequencies will seem to be coming from near the inner edge of each speaker. That is, from the right edge of the left speaker, and from the left edge of the right speaker. This is easy to hear with music, and with your ear close to the speaker. Only the panels are left/right oriented. The bases and interfaces are identical.

I think I have a Spectra 2200/3300 manual in my archives - it has the procedure for assembly/disassembly, which is basically the same for the larger speakers. I will send it if I have it. Disassembly prior to shipping, or even moving the speaker (other than sliding it a short distance on the floor) is ESSENTIAL. The frame cannot withstand the twisting that would result from moving the speaker with base and interface attached. And when sliding the speaker on the floor, grip it by the base and/or interface. Do not handle it by the frame. I speak from experience on this last subject. I bought a pair of used Spectra 4400s that had, prior to my acquisition, been picked up with the interfaces and bases attached. I had to do a fair amount of repair to the frame as a result. The bases were also water-damaged, but that's another story. The speakers now look and sound great, and I will never part with them! I joke (?) with my wife that I want them playing at my funeral. Good Luck!
 
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From my manual for the 6600 "Spectra arrays are MIRROR IMAGE. Each is identified by a small hole located in the TOP METAL CAPTURE PLATE, as well as a coloured dot on the bottom surface of the bottom surface of the array. Red for right and Green for left. The hole is on the LEFT side of the Left Array and the Right side of the array when viewed from the listening side"
 
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Attached is the Spectra 22/33 owner's manual, which will help with assembly/disassembly. Also attached is a preliminary copy of the Spectra 4400/6600 owner's manual (text only, no diagrams). Also attached are some of the missing diagrams for that manual, schematic, board layout, etc. Have fun!
 

Attachments

  • MK2146 Schematic.pdf
    213.7 KB · Views: 16
  • MK2146 Board Layout.pdf
    171.6 KB · Views: 10
  • 6600 Impedance Plot.pdf
    33.5 KB · Views: 7
  • Spectra 6600 OM.pdf
    28 KB · Views: 12
  • Spectra 22-33 OM.pdf
    1.4 MB · Views: 10
  • Spectra sectors-color codes.pdf
    424.8 KB · Views: 8
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@AcoustatAnswerMan Thanks again for all the documentation- it will be very useful!

I have a general questions about amplifiers that may be of interest to others...

I have a pair of model 3 Acoustats I picked up a few weeks ago. They have the mk-121-c interfaces with the medallion transformers. My question regards amplifier power...

I have a class d Hypex nc1200 amp rated at 1200/700/400 watts into 2/4/8 ohms. This is peak, not rms power. When I used this amp with the model 3's, I was getting an average speaker level output of around 70dB with 85db peaks at about -20dB on my volume control. This is about as loud as I would normally listen, typically I would listen at around -25dB. I have been told that the transformers in the interfaces are rated at 200Wrms. The rms or continuous power output of the amp is probably about a third to a quarter of the peak power output values listed earlier. Further, the actual impedance of the model 3 only dips down to 1 ohm or so at high frequencies where there is little musical energy. Am I correct to assume that I will not be saturating the transformers at these listening levels? How would I know when the transformers are saturated?

Thanks for any input.