op amp/dac data sheet help

[Smiffy]

Hi All
looked all over.Can anyone point me to datasheets for the following
Burr Brown PCM1700U dac chips(18 bit i think)
NEC C4570C op amps
All in a Pioneer SP-99D dolby AC3 decoder.
Any help greatly appreciated.
Smiffy

 

[Netlist]

Hi, Smiffy

The PCM1700U idatasheet is here:
http://manuales.elo.utfsm.cl/datasheet/burr-brown/PDFFILES/DATASHTS/PCM1700.PDFs

The UPC4570C datasheet is here:
http://www.necel.com/nesdis/image/G10528EJ6V0DS00.pdf

/Hugo

 

[Smiffy]

Hi Hugo
Many thanks.Much obliged
Smiffy

 

[jean-paul]

Replacing the C4570 will be worth the trouble. They sound awful compared to even NE5532. Last time I saw them in a DCD2700 I replaced them for OPA2604 which was a big improvement.

 

[Smiffy]

Hi Jean Paul
Exactly what I was thinking
OPA2604s or similiar(AD8620?).But always have liked the OPA2604.nice sounding little op amp for very little money.Got about 10 lying around.Looking for a workshop manual but as Im in the UK and the SP99D was only released in the US im finding it difficult.First priority is getting rid of the fan that cools the vreg heatsink.driving me nuts.need to find out which ones are the hot ones.Thanks for advice.Smiffy

 

[XTAL]

Hi Jean Paul
OP2604 is pin to pin compitable with NEC C4570C?

Thanks

 

[XTAL]

And can I use 2 piece OPA627 to instead a NEC C4570C?

 

[jean-paul]

Hi Jean Paul
OP2604 is pin to pin compitable with NEC C4570C?

Thanks

Yes.

 

[jean-paul]

And can I use 2 piece OPA627 to instead a NEC C4570C?

Yes, but it'll be an expensive solution and you can have problems finding/designing adapters. Besides that other things can come up because of longer wires, proper decoupling etc. I would go for a good dual opamp.

 

[XTAL]

Thanks a lot.
As your experience. OPA2134 & OPA2604 which one is better to instead?

 

[klitgt]

Replacing the C4570 will be worth the trouble. They sound awful compared to even NE5532. Last time I saw them in a DCD2700 I replaced them for OPA2604 which was a big improvement.

I want to do something to a Denon DCD3560 which is a great transport but with some low-end opamps in the analog part.
I have attached a simplified schematic diagram for reference.
The DAC chips are BB PCM58K followed by uPC4570C opamps for I/V conversion, NE5532 for low pass filtering and NE5534 for output buffering.

I have read in some Danish forums that the uPC4570C should definitely be replaced by NE5532 and NOT by ANY jet based opamps. Maybe those people are religious about bipolar opamps since they hate fets so much!?

The OPA2604 datasheet mentions among the applications "PCM DAC I/V conversion". And you have used and recommended the OPA2604!

I am confused about these apparent contradictions.
Any ideas to replacements of the 4570, 5532 and 5534s?
Thank's in advance

 

[klitgt]

Replacing the C4570 will be worth the trouble. They sound awful compared to even NE5532. Last time I saw them in a DCD2700 I replaced them for OPA2604 which was a big improvement.

Sorry if this appears more than once, but something seems to have gone wrong for my PC.

Do you Jean-Paul mean that OPA2604 is better than NE5532 as I/V converter? I have seen in another forum that NE5532 gives a lot of slam in the bass while OPA2604 gives a more sweet and liquid sound with less slam in the bass as I/V converters. Do you agree?
I have even seen that OPA627 as I/V converters are for those who want a direct and "right into the face" CD sound that discloses the difference between CD and vinyl?

What about OPA2604 as I/V converters and OPA627 as buffers?