Bi-amping ADS L1290 speakers

[dscalderon]

I recall reading a long ago thread about modification(s) to the ADS C2000 bi-amplification unit to be compatible with ADS L1290 speakers and perhaps L1590 speakers as well. Can anyone tell me the modification(s) needed to the ADS C2000 to run the ADS L1290 speakers in bi-amp mode? Can anyone comment on using the C2000 without the modification and the impact on the L1290s performance? Thanks in advance for any information.

 

[jdurbin1]

These notes are from the factory schematic for the C2000:

C-2000 is not designed to work with L1590 speakers.

As per ADS memo, remove capacitors 38 and 39 (dark red in middle of right side).

Use program switches all down (300 Hz, 0.68 Q).

C-2000 will work well now with L1590.
​

They left out to set the crossover switch on the front panel to the Prog. setting.

Given the L1290 shares a similar dome mid, the settings for the L1590 should work for it as well. Can experiment easily enough though; the owner's manual covers changing the crossover frequency (300, 400, 500, or 600 Hz) and Q (0.68, 0.58, 0.44, 0.33).

John


P.S. Haven't had a chance to set mine up yet so can't comment on the stock or modified performance. I'm planning to try it stock first on L1230's, then mod and try on my L1290/2.

 

[Liefloff]

These notes are from the factory schematic for the C2000:

C-2000 is not designed to work with L1590 speakers.

As per ADS memo, remove capacitors 38 and 39 (dark red in middle of right side).

Use program switches all down (300 Hz, 0.68 Q).

C-2000 will work well now with L1590.
​

They left out to set the crossover switch on the front panel to the Prog. setting.

Given the L1290 shares a similar dome mid, the settings for the L1590 should work for it as well. Can experiment easily enough though; the owner's manual covers changing the crossover frequency (300, 400, 500, or 600 Hz) and Q (0.68, 0.58, 0.44, 0.33).

John


P.S. Haven't had a chance to set mine up yet so can't comment on the stock or modified performance. I'm planning to try it stock first on L1230's, then mod and try on my L1290/2.

Hi John, thanks for posting these details. I have a question. Once you remove Capacitors 38 and 39 do you just leave the circuit open where the capacitors were?

 

[jdurbin1]

I'll have to check the notes on my copy of the manual... don't recall offhand.

John

 

[jdurbin1]

Notes just say to remove them, so I would say yes.

John

 

[Porkloin]

On/Off switch......what's that?

 

[Liefloff]

Notes just say to remove them, so I would say yes.

John

Thanks John.