18 replies to this topic

[sean]

Hey all

Just wondering - my Nakamichi CD-700 has a digital output and I am going to be using a processor which doesn't have digital input (only analogue).

I do have a digital to anologue convertor which should be compatible with it.

Are they benefits which come from going digital - less intruduced noise etc?

90% sure I will go ahead with it but just wondered about any pros ond cons beforehand...

thankyou

[Revolution.]

from my knowledge of SPDIF in home thetre, for transfering audio from a cable (opticial/coxial)

you only recieve 96KHZ max but yet its also digital, analog inputs contain a transfer rate of 192khz.

so you kinda get the idea, so in saying so its really an option for people who have dolby digital/dts encoded

car thetre systems in the car to actually be bothered with it as it provides a 5.1+ environment, and digital would be the way to go for achieving it.

so yeah my opinon i wouldnt go for it unless you have movies playing in the car that have dobly digital encoded etc

btw: if your going to go digital, dont bother spending hours of dollars with cables.

digital is digital, it doesn't need the unncessary junk of 200 dollar cables for just some dipped gold connectors.

for example HDMI spending video, not necessary to buy a 100 dollar cable compared to a 5 dollar one, doesnt matter.

hope that helped abit .

but what would i know, i havent done it in my car... so yeah.

Edited by Revolution., 09 April 2009 - 11:51 PM.

[sean]

Thanks Revolution

[shiny_car]

i doubt you'll hear a difference. it depends what you are changing 'from'; in your case, the Nak is already a top quality CD HU, so its analogue outputs will be superb.

then consider the quality of your DAC. is it any better than the DAC inbuilt into the Nak? is it audibly different?

put it this way, i've tried analogue vs digital with my alpine gear. firstly, the CDA-7998R HU which was one of their best. i couldn't hear any difference between analogue and digital. then the F1 CDA-7990R...again, couldn't hear a difference. the analogue is so good, the digital is not significantly better. i think this can be applied broadly across most high-end gear.

however, if it's cheap and easy, do it. why not? and in some systems, it can save money or hassles with alternative cabling. a single fibreoptic digital cable could replace multiple sets of RCA cables; so it's neater and easier to install.

[sean]

I was actually thinking of using the DAC from the other Nak I have! (MB-100).

It's a separate box with all the input ranges etc built into it and the digital signal plugs straight into it.

Is there a reduced chance of noise going digital though? (with just one RCA going from HU to the DAC instead of the Twin RCA's).

The digital signal from the Nak is a single RCA (not optical in this case) so I don't know if that changes things!

[Fury♫]

Revolution., on Apr 9 2009, 11:50 PM, said:

from my knowledge of SPDIF in home thetre, for transfering audio from a cable (opticial/coxial)

you only recieve 96KHZ max but yet its also digital, analog inputs contain a transfer rate of 192khz.

so you kinda get the idea, so in saying so its really an option for people who have dolby digital/dts encoded

RBCD is 44.1khz

Why would anything else matter?

[shiny_car]

sean, on Apr 10 2009, 12:11 AM, said:

I was actually thinking of using the DAC from the other Nak I have! (MB-100).

the DAC is probably not going to be any better than the one inbuilt into the CD700, right? you may have specs or info on this.

i don't think you'll have any benefit, and possibly be worse off if the DAC isn't as good.

Quote

Is there a reduced chance of noise going digital though? (with just one RCA going from HU to the DAC instead of the Twin RCA's).

The digital signal from the Nak is a single RCA (not optical in this case) so I don't know if that changes things!

the RCA style is no issue.

with analogue, noise won't be an issue so long as you follow the usual principles of installation. if you end up with excessive hiss or whine, and you can't fix it any other way, then that's probably a case to change to digital, and mount the 'external' DAC as close to your processor as possible, which is presumably going to be in the boot?

[sean]

Thanks shiny and fury

Guess with every extra component in the signal chain there lies more chance for induced 'noise'.

So when I have the seats and everything else this weekend applying some 'barrier-type' sound deadening I will do some more work on my wiring! Got about 30 meters of Techflex (big enough for two runs of 0 gauge) so my RCA's can live inside that!

[Pulse-R]

if you want, I can test the DAC for you and give you a 'good or bad' report.

if it's using the co-axial input, there's no noise-cancelling advantages. that's only for optical, as it breaks the electrical signal path

[Marc ♫]

From my experience with my very sought after Precision Power DAC ...

This one actually has an analogue pass-through for radio etc. In a few of my setups I have had the ability to literally swap back to back between digital and analog. The difference is absolutely night and day. Detail, clarity, noise etc. Cyberpunky (and maybe a few others) might remember when I did the swap outs. The difference really was amazing.

That being said, I had a nakamichi dac, that I did some back to back tests against the PPI with and the difference was also night and day in the digital domain. The Nakamichi sounded lifeless and dull (similar to analog) when compared to the digital of the PPI. Go figure!

[fuddbutter]

thats cause the old skool PPI was the %hit!!

[Alfie]

if the processor is digital then it has to convert the analog back to digital to process it before converting it back to analog to go to the amp.

so it would be digital off the CD, then converted to analog then converted back to digital to be processed before being converted back to analog.

Whereas, digital its digital all the way out of the head unit, into the processor and only gets converted to analog after processing, and is immune from the noise that the unbalanced analog picks up.

Even if the converters in the head unit are superior to the converters in the processor, this is negated when you convert back to digital in the processor and then use the inferior converters to convert back to analog, as well as the jitter, artifacts, etc from 2 different master clocks whereas S/PDIF contains clock and greatly reduces jitter (dependant on master clock)

[Pulse-R]

S/PDIF is more susceptible to jitter due to the clock needing to be recovered.

if you can't sync. all the clocks, then they all have to be excellent.

most processors use 48 or 96kHz internal, so they have to re-clock the data anyways and usually have a sample rate converter on the input.

[Alfie]

Pulse-R, on Apr 11 2009, 04:07 PM, said:

S/PDIF is more susceptible to jitter due to the clock needing to be recovered.

if you can't sync. all the clocks, then they all have to be excellent.

most processors use 48 or 96kHz internal, so they have to re-clock the data anyways and usually have a sample rate converter on the input.

wouldnt it be better to be re-clocking the signal then converting it between A and D more than necessary? at least then its only maths and not signal conversion?

[sean]

I'm lost now! I thought being one RCA from the CD700 it was still 'digital' (obviously I don't know enough about these things yet!)/

Pulse-R, thanks, I'll be in touch