Alesis Xt Or Xt20?

[Mastabeta 57]

:CONFUSED:

Well, I have done some research and cannot find much of the specs on the "Alesis XT" model adat. I know the XT20 is a newer model but I can score the XT for a reasonable price used.

So heres what I gather from the XT20, it has balanced I/O provided threw the elco adapter... does the XT have this?

The XT20 records at 24bits uncompressed... does the XT record at this rate as well?


Any other info would be greatly appreciated about the XT model.
(ie. a webpage or replies)

[Wireneck]

The xt records at 16 bits, i believe this is the main difference between the xt and xt-20. Im sure there are a few other improvements as well.

[eh91311]

The primary difference between the XT and XT20 is the bit rate for the A/D and D/A converters. The XT records at 16 bit, 44.1 or 48khz, the XT20 at 16 bit, 20 bit,. 44.1 or 48khz. The original blackface ADAT records at 16 bit, 48 khz only. The original, XT and XT20 all have balanced I/O via the elco.
It's your decision whether or not the XT20's higher bit resolution converters are worth the extra $.

[Blue Bear Sound]

Not only that -- the converters are not only expanded resolution, the sound quality is significantly smoother on the XT20s........

The other big benefits are a more robust transport with faster lock-up/sync times.....

[foreverain4]

the xt20 also has a mode that you can record up to 24 bit. but you loose 2 tracks, making a total of 6 per unit. i have never recorded this way, but i read that somewhere.

[Mastabeta 57]

i'll hold of until i can get an XT20. I read another benefit for having the 20bits as opposed to 16. since most cds are produced at 16bits, recording at a 20bits leaves you with more headroom for when you master down to a cd. say depending on the dynamics, if you record on a 16bit, you may only actually be using 14-15bits. so when you master to cd at 16bits you are only increasing the volume/distortion.

maybe i am confusing this but heres where i found what i read...
UNDER THE, "Why 20 bits?" section
http://www.sospubs.co.uk/sos/may98/a.../adatxt20.html

thanks,
Blue Bear Sound
eh91311 &
Wireneck

[Mastabeta 57]

Originally posted by foreverain4
the xt20 also has a mode that you can record up to 24 bit. but you loose 2 tracks, making a total of 6 per unit. i have never recorded this way, but i read that somewhere.

WOW! 24 bits hmm, an even better reason to choose the XT20!

thanks foreverain4

[Blue Bear Sound]

Originally posted by foreverain4
the xt20 also has a mode that you can record up to 24 bit. but you loose 2 tracks, making a total of 6 per unit. i have never recorded this way, but i read that somewhere.

This I have never heard........ (doesn't mean it's not true, but it's news to me!)

[foreverain4]

i think you have to have external converters that are connected to the adat via lightpipe, as the converters on the adat itself are only 20 bit. i will have to check the manual when i get home.




lynn

[foreverain4]

here it is, straight from the manual of the xt20. on pg 113, in the digital recording concepts section.





"If your application is extremely critical, it is possible to record at 24-bit
resolution on your ADAT-XT20 using external adapters (i.e., the Rane
PAQRAT or the Yamaha 02R). This method takes the “extra” bits and
records them on higher tracks, so you won’t get eight tracks without
using more recorders and adapters."


lynn

[Stefan Elmblad]

Originally posted by Blue Bear Sound
Not only that -- the converters are not only expanded resolution, the sound quality is significantly smoother on the XT20s........

The other big benefits are a more robust transport with faster lock-up/sync times.....

My understanding is that the ADAT XT has the most reliable transport system of them all. The LX20 and XT20 is somewhat flimsier constructed.

[foreverain4]

i have an xt and (2) xt20s. i had the xt last in the chain but i have switch it to the master because the thing sometimes just would not chase the xt20's. didnt happen all the time, but enough to tic me off! lol i put it to master, and, in my opinion, the 20's do a tremendously better job of chasing.




lynn

[Blue Bear Sound]

Originally posted by Stefan Elmblad
My understanding is that the ADAT XT has the most reliable transport system of them all. The LX20 and XT20 is somewhat flimsier constructed.

No so... the XT20 and the XT have the same more-robust transport - the only difference is the converters...

[Blue Bear Sound]

Originally posted by foreverain4
here it is, straight from the manual of the xt20. on pg 113, in the digital recording concepts section.





"If your application is extremely critical, it is possible to record at 24-bit
resolution on your ADAT-XT20 using external adapters (i.e., the Rane
PAQRAT or the Yamaha 02R). This method takes the “extra” bits and
records them on higher tracks, so you won’t get eight tracks without
using more recorders and adapters."


lynn

Well there ya go!

I wonder how many use it this way, though - I don't think it's too common!

[foreverain4]

i know, i havent even messed with it. i would rather have 8 tracks at 20 bit than 6 at 24. i, personally, think the difference between 20bit and 24bit is somewhat trivial. i know there is a difference. but not much to the human ear. there is, however, a dramaticly noticeable difference between 16 and 20 bit.



lynn

[Stefan Elmblad]

Originally posted by eh91311
The primary difference between the XT and XT20 is the bit rate for the A/D and D/A converters. The XT records at 16 bit, 44.1 or 48khz, the XT20 at 16 bit, 20 bit,. 44.1 or 48khz. The original blackface ADAT records at 16 bit, 48 khz only. The original, XT and XT20 all have balanced I/O via the elco.
It's your decision whether or not the XT20's higher bit resolution converters are worth the extra $.

My ADAT XT's got 18bit A/D and 20bit D/A.

[foreverain4]

where did you get this info?

[Blue Bear Sound]

Originally posted by Stefan Elmblad
My ADAT XT's got 18bit A/D and 20bit D/A.

Yes - that's the spec of the converters, but it is functionally only 16-bit....

[Stefan Elmblad]

Originally posted by foreverain4
where did you get this info?

The specs are in the manual.

[Stefan Elmblad]

Originally posted by Blue Bear Sound
Yes - that's the spec of the converters, but it is functionally only 16-bit....

What you are saying is that Alesis is wrong about their own converters they developed. Could you please explain this a bit further ?

[foreverain4]

the converters are as you say, but it only records 16bit to tape.

[Blue Bear Sound]

Originally posted by Stefan Elmblad
What you are saying is that Alesis is wrong about their own converters they developed. Could you please explain this a bit further ?

I'm saying that while the A/D chips are spec'd higher, the XT unit is designed and records at 16-bit with either a 44.1kHz or 48Khz sampling rate.

They did not implement a design to match the maximum spec on the chips they used........

Ged'dit???

PS - if you don't believe me, then run a digital signal from tape into a bit-check tool - you will see it is a 16-bit digital signal.........

[Stefan Elmblad]

Is this a effect that happens when it goes to tape or in the converter itself? In other words, if I record I get 16, but what do I get if I only use the A/D's and route a signal from line in to optical out ?

[Blue Bear Sound]

I know that when I routed a 24-bit signal thru the the XT20s, it was truncated to 20-bit (even though the signal didn't pass thru the A/D converters), so I suspect it would be the same for the older XTs............