how to harman/kardon hd 970 sounds better

[vujnovic zex]

Help please.What can i do to my player to sound stronger?If i make some changes in i/v conversion(for example change resistor in negative feedback of op amps op 275) or some other change in output differential stage, will that make some difference(or something else )thanks

 

[HornTube]

Put some Sowjet tubes (6N6P on high current - not in SRPP mode) after the i/v section. Get rid of the diamond buffer output stage and all the 1000 parts. Use K75-16(24) caps for the tube signal section and there you go.

 

[SoNic_real_one]

What can i do to my player to sound stronger?

Use a "stronger" power amplifier than the current one?

 

[HornTube]

Use a "stronger" power amplifier than the current one?

I think he means bolder/dynamics/body/drive/energy...

 

[SoNic_real_one]

First of all - look for the latest firmware update - V4.4. There are 2 different versions: one for the ones with the loader mechanism DSL710/720A and another for the loader mechanism DV345/HD65.
Second - the output stage is one of the best in this class of players. You can try different OpAmps instead of the original I/V (OP275), but that is already a very good OpAmp.
LM4562, AD8652 or even OPA1642.

PS: Using tubes as I/V stage will just cripple it.

 

[vujnovic zex]

thanks a lot

 

[eherle]

Harman Kardon HD 970 firmware

First of all - look for the latest firmware update - V4.4. There are 2 different versions: one for the ones with the loader mechanism DSL710/720A and another for the loader mechanism DV345/HD65.

I cannot find this firmware on the HK sites (NL & US). The service manual explains how to upload the firmware, but does not tell where to get it. Where can I find this firmware?