cd to cdr truncating?

[promesis]

i am new to pushing digital signals around thru s/pdif while monitoring analog signals. i am experiencing problems with this set-up to "pseudo-master" a pre-recorded CD to another CD:
CD Player S/PDIF Out ---> to
Finalizer Express S/PDIF In /Out ----> to
CD-Recorder S/PDIF In ---x

everything sounds fine while monitoring the pass - but upon listening to the final recorded CD - there are these intermittent quick nulls of silence.. thru my investigation - i believe this is "truncation". diagnosis sound correct so far?

i believe this is happening between the Finalizer and the CD-R. Because, the manual states that "When one of the dither LEDs are lit, [i set it to 16bit for CD] dither noise is applied to the digital outputs. However, the signal is not truncated as the Finalizer Express always outputs 24 bit data." This means (to me) that any truncation must be applied at the receiving device - in this case the Tascam CD-RW700. Which after studying their manual is mute on the subject other than "the digital direct mode bypasses some of the input circuitry (the freq. converter and the digital level control) .." i know that the dig. frequency is correct @ 44.1kHz because it inputs correctly to the receiving device - which would not if there is a frequency mis-match and will alert me to this thru an error message.

my somewhat ignorant analysis is:
i think that the original CD is 16 bit / 44.1kHz ---> then when it hits the Finalizer it gets converted to 24bits ---> then because it states clearly that despite the dither setting (@ 16bit) the unit ALWAYS outputs all 24bits of info --> the Tascam (i am inferring) simply accepts the bit rate sent thru the S/PDIF. Alas .. that funky glitch from the poor little Tascam truncating the signal.

Like i said - i don't know diddly about this.. strictly dealt with pushing the analog signal around. Any suggestions or analysis - am i correct in my theory?

The only possible work-around i have imagined would be to bypass all that wonderful digital nice-nice and push all that signal through all the A/D D/A converters on all of the units.. or .. i have several outboard units - one is the Kurzweil Rumour (or the TCE M-One) which i could add between the Finalizer and the CD-R. This unit will give me the option to reduce the digital output signal to 16bits - then pass that out thru its S/PDIF to the Tascam.. is this a sound approach?

Now, i am not looking for an "easy pill" i plan to experiment - but i want to be aware of what is going on here and if i am demonstrating some level of understanding while identifying the limitations of the gear.

TIA.

 

[Massive Master]

Sounds like a clocking problem - Definitely not truncation.

In most cases, the effects of truncation aren't even audible. But the effects of clocking issues (clicks, pops, gaps) are usually glaring.

 

[promesis]

clocking?
i have tried setting the Finalizer's "Sync From" toggle to the "Internal 44.1" as recommended by the manual - and then to "Digital Direct" - forcing the Finalizer to accept any external clock info from the S/PDIF.. same results.
The Tascam's manual is mute on the subject. It describes that different sample rates will cause digital "clicks" .. not sure if they are describing an audible "click" - but what is happening would, to me, be the opposite of an "audible click" - but a super quick blank "null".

crap.. could it be that the CD player and CDR are just not robust enough to handle these digital connections - thus rendering a prognosis of all analog funness? why would these devices even have these digital connection options and be so impotent?

i do have a MOTU 896 just sitting in the box - i could use that as an external clock.. but if my previous statement of lack of robustness is the culprit- i suppose it is meaningless.

i'm going to ride up there now and mess around with this stuff.. should be getting my adapters tomorrow to down-shift to fully analog utilization of these pieces of gear. "using stone knives and bearskins" - spock

thanks john.

 

[mshilarious]

crap.. could it be that the CD player and CDR are just not robust enough to handle these digital connections - thus rendering a prognosis of all analog funness? why would these devices even have these digital connection options and be so impotent?

No, it's a just a clocking issue, perhaps combined with latency, although I would think latency would be taken care of. Anyway. The Finalizer manual says its clock source is automatically set to a digital input when that input is selected. So your input selector should be S/PDIF, and the Sync From control should be as well. Your CD player should presumably run off its own clock, but I would check that.

One very suspicious statement is that the silence only occurs on the burned CD, but not when monitoring? I presume you mean monitoring on the CD burner? That means there could be some sort of buffer problem when burning the CD. Reading the Tascam manual, it could have something to do with its Sync Record feature, or maybe try the Digital Direct feature? What happens when you plug the CD player straight into the Tascam, bypassing the Finalizer?

 

[Massive Master]

You *must* sync *FROM* and external source if the external source is the clock.

Unless you're running a common clock to all piece in the chain (which I'm assuming you're not) you need to allow the TCF to be clocked by the piece before it. Hopefully, the recorder will know enough to allow it to be clocked by the chain also. I can't remember if the TCF has a digital "through" or what not or if it's screwing things up at the output...

 

[promesis]

bingo!

clocking it was. apparently i was in error when i stated that i had tried both the "Internal Sync 44.1kHz" and the "Digital Direct" on the TCF.. maybe late @ nite/too many heinekens - undoubtedly frustration being a factor.. but tonight i set up some controlled experiments - jockeying between the two settings. this revealed the 'hiccup" in the "Digital Direct" mode only.

part of figuring out and understanding a problem is the ability to replicate and fix the problem at will - i'm such an Aristotelean dork. i could monitor the CDR through headphones and was able to create the "glitches" and fix it. then recorded several passes in the different modes with the same consistencies.

One very suspicious statement is that the silence only occurs on the burned CD, but not when monitoring? I presume you mean monitoring on the CD burner?

yeah.. i knew this was coming as soon as i wrote it. but no, i was only able to monitor through the TCF analog outputs to the monitors the other nite - then subsequently listened to what was recorded. i could only empirically confirm that the signal from the "parent" CD passed unmolested to the TCF then to the monitors - i should have specified this in my OP. this lead me to believe that the problem was between the TCF and the Tascam as the recorded CDs revealed the glitch. tonight i was prepared to set up a more precise monitoring scheme making for a more efficient process.

thanks to both for your help and guidance.

hey mshilarious.. i noticed you are in the OBX.. i'm right "up the street" in norfolk ... sure is dang cold 'round here. at least no snow, eh?

 

[mshilarious]

hey mshilarious.. i noticed you are in the OBX.. i'm right "up the street" in norfolk ... sure is dang cold 'round here. at least no snow, eh?

No way, man, I've got TWO INCHES! And it's not even going to melt until tomorrow! I want my money back!

The kids enjoyed it though--the younger ones hadn't ever really seen snow (we moved from Fairfax in 2005).

Massive is laughing at us right now--hey Massive, one time I was in farview's town on a business trip, it's like 15F and snowing, and the fire alarm goes off in our building. Outside were a group of Nigerians. Naturally, they did not own coats

 

[SouthSIDE Glen]

Lightweights!

Never trust someone from a part of the country that uses sand to polish icy roads to a Zamboni-like finish.



G.

 

[mshilarious]

Lightweights!

Never trust someone from a part of the country that uses sand to polish icy roads to a Zamboni-like finish.



G.

Oh, it's worse than that here. There is no sand, no salt, no snow removal equipment, period. It hardly ever accumulates for more than one hour, so there is no budget for it. I think the last measurable snow was in 2003.

On the other hand, we do have plenty of sand removal equipment, as Rt. 12 gets overwashed all the time . . . and I'd like to see you sissy boys take a hurricane!

 

[promesis]

No way, man, I've got TWO INCHES! And it's not even going to melt until tomorrow! I want my money back!

ouch! must say i am kind of surprised.. like y'all we'll see maybe a flurry or two every couple of years - that's of course only in the air!

i do miss it sometimes - grew up in southern maryland - lots of accumulations .. and mom lives up on the northern neck va .. driving up sometimes on rt17 i could see the "freeze line"... one year i swear it was so distinct that even on car hoods, parking lots and fields - one side: ice and snow the other side just wet.. was sort of creepy .. like driving into the twilight zone (and not just cause i was going to my folks')

cheers - and stay warm!

 

[SouthSIDE Glen]

I'd like to see you sissy boys take a hurricane!

We're too busy laughing at tornadoes, thank you very much. And that's just our little sisters... we chase after them, just for the sport of it. [pounding fist in the air: "whoof whoof whoof!"]

Then again, I guess we can't go by natural disasters; those Californicators can throw mudslides, widfires and earthquakes in our faces, ye we all know what girly men they are . [Excuse me while I run and hide from Sonic Al before he throws a couple of summing boxes at my head , Just kidding, West coasties! ]



G.

 

[mshilarious]

You're comparing a tornado to a hurricane? A hurricane can spit off a dozen tornadoes without even noticing

Oh, and we have wildfires, too. Last summer, 40,000 acres burned 100 miles west of my house. Sounds far away, but the smoke and even ash hung over the whole area for nearly a month

Y'all need a good ol' fashioned prairie fire!

 

[SouthSIDE Glen]

Y'all need a good ol' fashioned prairie fire!

We have a new invention around here; it's called a fire department!

We don't get much of that because we're surrounded mostly by corn fields. Yeah I know, very boring. The Chicago are is surrounded by pretty solid ring of forest preserves, but usually the only fires that get started around there is when the county sheriff finds a renegade hidden field of pot plants hidden deep in the woods somewhere and start their own bonfires to destroy them.

G.