Altec Lancing ACS41

[budm]

These are pictures and spec sheets of the IC's

[Andrew F. Ali]

Re: Altec Lancing ACS41

I still have this system on my computer. It has worked quite well over the years and still sounds superb. Music is smooth and clear. Newer systems I tried don't give me that 'thump' I like to hear. Good one, budm.

[redwire]

Re: Altec Lancing ACS41

These are good systems and worth repair/recap. I have an ACS48 coming in for repair and it looks really well built.
You can change out the LM324 for a better op-amp with less cross-over distortion, which cleans it up.

[nomoresonys]

Re: Altec Lancing ACS41

Hello Redwire, can you tell me what to replace the KIA324P with and should I replace both, that's if I get them working again.

[redwire]

Re: Altec Lancing ACS41

I know the LM324 has a gritty sound/mid-range blare to it due to the cross-over distortion so I change them out. Quad op-amp alternates:
LM837 is older and drop in. OPA4134 is very good as well.
The LM833 and OPA2134 are the high performance duals, to ditch the NJM4560 but it is not as bad.

[nomoresonys]

Re: Altec Lancing ACS41

Thank you.

[budm]

Re: Altec Lancing ACS41

TA8248, TA8229. Notes: (***V) Voltage with headphone plugged in. When headphone is plugged in the VCC2 from the switched headphone jack is cutoff so there will no VCC2 on pin 8 of the TA chip.
Pin 1: N.C.
Pin 2: Bootstrap 2 =18.20V (0.56V)
Pin 3: Output 2 = 9.42V (0.51V)
Pin 4: VCC1 = 18.47V (18.47V)
Pin 5: Output 1 = 9.03V (1.00V)
Pin 6: Bootstrap 1 = 18.16V (0.52V)
Pin 7: PWR-GND
Pin 8: VCC2 = 18.47 (0.05V)
Pin 9: Ripple filter = 9.63V (0.51V)
Pin 10: NF1 (Negative Feedback 1) = 0.60V (0.95V)
Pin 11: Input 1 = 0.06V (0V)
Pin 12: Input 2 = 0.02V (0V)
Pin 13: NF2 (Negative Feedback 2) = 0.60V (0.56V)
Pin 14: Pre-Gnd 1
Pin 15: Pre-Gnd 2