[sbelyo]

Has anyone listened to both in the same circuit? I am getting ready to swap the op amp in my DVD963sa. The one in there is AD8032. LC Audio reccomends the 8066 and even includes it in their re-clocking kit. I just wasn't sure if the 8620 was newer or better, or both? And since it's soic I really only want to do it once.

 

[rickcr42]

you need to double check your voltages before attempting a swap.I am pretty sure the 8066 is a +/-12VDC MAX chip (as are many of the newer opamp chips) and using it with a +/-15VDC supply will wipe it out.Not positive but prettyy sure

 

[sbelyo]

I thought about that this morning... I'm safe with voltage because the current op amp get +/- 8v and the 8066 is rated 5 - 24 volts.

Here's a very interesting side note:
Philips is giving the 8032 +/- 8 volts and it's max rating is +/- 5 volts with it's spec'd voltage at 2.7 Talk about being over-worked

It's hard to believe that they'd do that, but it doesn't suprise me in the least. I got the same feeling when I figured out that the guages in my mustang only have three readings OFF, ON, and OH NO!

 

[motherone]

Quote:

Originally Posted by sbelyo I thought about that this morning... I'm safe with voltage because the current op amp get +/- 8v and the 8066 is rated 5 - 24 volts. Here's a very interesting side note: Philips is giving the 8032 +/- 8 volts and it's max rating is +/- 5 volts with it's spec'd voltage at 2.7 Talk about being over-worked It's hard to believe that they'd do that, but it doesn't suprise me in the least. I got the same feeling when I figured out that the guages in my mustang only have three readings OFF, ON, and OH NO!

I haven't looked at the datasheets in a while, but I seem to recall the 8066 being a much faster chip than the 8620. You may have more stability issues with the 8066 than the 8620 if the circuit isn't well decoupled.

 

[rickcr42]

Quote:

I thought about that this morning... I'm safe with voltage because the current op amp get +/- 8v and the 8066 is rated 5 - 24 volts.

That's cool.That 5-24 volts IS the minimum and maximum spec so good practice would be to go a bit higher than the 5 (+/- 2.5 volts) and a bit lower than the 24 (+/-12 Volts).the bottom range for voltage swinging under load and the upper figure to prevent a shortened life or noisy operation.common with opamps drivien right to the edge continuously.
some chips can have a "sweet spot" which isd a narrow band of voltages where they flat out sound right while they sound like pure crap outside that band.

Quote:

Philips is giving the 8032 +/- 8 volts and it's max rating is +/- 5 volts with it's spec'd voltage at 2.7 Talk about being over-worked

hard to beleive it is getting +/- 8 Volts right at the voltage pins without some form of voltage reduction.If not then expect a short and noisy life for that chip.There is another possibility and that is special "select" versions of that chip made for Phillips.not unheard of to have a special or MIL-spec chip be other than the data sheets say

Quote:

I got the same feeling when I figured out that the guages in my mustang only have three readings OFF, ON, and OH NO!

Older cars had it right-an actual "guage" for each function so you could not just monitor if somethng is a go or no-go but watch the performance curve in action.Modern "idiot" lights are no more than a "you are fine" and "totally screwed" indicator or like you put it ,an "uh oh" light

 

[morsel]

Quote:

Has anyone listened to both in the same circuit?

I did, and prefer the AD8620.

 

[blomquist]

I don't know if this isn't a little bit o.T. but if it should directly drive a headphone take the AD8397 - a real superb driver opamp - when powered +-12V this thing drives almost all from 16Ohms to 600Ohms. another excellent job done by Analog..

 

[sbelyo]

Quote:

Originally Posted by rickcr42 hard to beleive it is getting +/- 8 Volts right at the voltage pins without some form of voltage reduction.

From what the schematic says and what the other guys that have modded this player say is that it gets +/- 13 volts pre regulated. Then it goes through a regulator and other parts getting dropped to +/- 8 Volts.

I myself can't confim it as I have not taken the lid off the player yet, but there is a guy in the diyaudio forum that is a Philips Engineer and he confirmed it to the rest of the guys on the thread.

Some rock and roll genius actually made a seperate regulated linear power supply for the op amp. The stock unit is a switching power supply thus generating unwanted noise.

I just don't want to rip apart the board to isolate the power rails. I'll be happy with swapping the op amp and putting in some blackgates and a filtered IEC inlet.

 

[sbelyo]

Quote:

Originally Posted by morsel I did, and prefer the AD8620.

Thanks....

I have a 8066 laying around, and since my modding budget for this palyer is $100.00 + or - it looks like that's going to be it. It sounds like a good choice for me because I like musicality over analytical