Altec Lansing Solid State Amps 1590B, 1590E, 771B, 771BX and "SYSTEM CABINET"

[tiefbassuebertr]

Altec Lansing Solid State Amps 1590B, 1590E, 771B, 771BX and "SYSTEM CABINET"

About this devices from Altec Lansing schematic diagrams wanted, additional the first date of release of all models.

Very interesting was the fact that the IM distortion are below detection limit - see data sheet - and thus less than the THD values.

I have found this URLs:

Altec Lansing's first solid state amp (?): "SYSTEM CABINET" -
Simplex XL Transistor Sound System
http://www.diyaudio.com/forums/multi-way/91372-altec-lansing-32.html (Post #312)
more informations here:
Yet Another Altec Page
and
Altec Amplifiers & Tube Amps | Vintage Electronics
but no exact informations about Simplex XL Transistor Sound System

Altec 1590B/1590E
Altec Lansing Professional Amplifiers Specification List
Altec Lansing Professional Amplifiers Specification List

Altec Lansing 771B and 771BX Electronic Crossover Bi-Amplifiers:
http://www.greatplainsaudio.com/vintage_altec/771B_BX_biamplifier_spec_sheet.pdf
http://www.greatplainsaudio.com/vintage_altec/Two Amps Are Better Than One 1970's_saleslit_ALL.pdf
ALTEC LANSING ELECTRONIC CROSSOVER BIAMP MODEL 770

 

[tiefbassuebertr]

Altec 1590 cont.

more pics from SS amp device 1590

 

[djk]

The 1590 and the 771 were kind of lame products from Altec.

The Molex connector on the heatsink of the 1590 always failed, it couldn't handle the current.

The 771 had weak outputs, and the main supply filter cap was run at higher voltage than it was rated for.

 

[mickeymoose]

What info do you want. I may be able to get my hands on it. No promisses though! E

 

[tiefbassuebertr]

What info do you want. I may be able to get my hands on it. No promisses though! E

the schematics I want to have.

 

[Soundude]

I have a few 1590e's too, but they are kinda distorted when playing...can't figure out why, voltages check but think has to do with the caps and there is a 50ohm pot thats wire wound and i think they burn up...kinda crusty feeling when turning..
Like to get these working, as soon as I finish my other amp project those are on the bench...
I have schematics and manual for the 1590e and the 15xx 50watter version.

 

[brianshep]

1590E with good sound

hello all well i researched the 1590 E transistor issue and found that the sd 424 transistors are a nice replacement .so i decided to give the one 1590 a nice test drive! hooked it up to a 8 ohm panasonic oldie but goody speaker 4 way with 12 inch sub. since there are no 8 ohm options on the outputs i opted for the 4.5 ohm tap. and ..suprising!!! nice ,smooth ,clean highs, tight bass,dead silent without signal, driving a 8 ohm load, seems people have given this tank of an amp a bad rap!! this amp sounds smoother and not as crisp as my adcom555. i think you would say warmer....more like tubes. as for your amp sounding badly i would look at the pre board on mine i found several resistors out of specs.

 

[Soundude]

get that sound because of the output transformer...
still trying to diagnose the distortion...any ideas anyone?

 

[brianshep]

the manual mentions adjustments on the pre board to control distortion caused by high transistor pre load voltage.its says these should be adjusted if the transistors have been replaced!.i didnt touch the pots on my pre board.and i changed 6 of the original 8 motorola 5878 transistors. and the amp sounds nice! i also change 2 resistors on the rail check them mine were way out of spec the big 22 ohm ones!

 

[djk]

http://alteclansingunofficial.nlenet.net/proelectronics/proamplifiers/1590E-Manual.pdf

 

[MonarkeIV]

I know this is a very old thread, but what were the differences between the 1590A and the 1590E besides the obvious difference in the switch and other cosmetics.