IS this JITTER??

  • Thread starter Thread starter johnfindlay
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quote - "Just got off the phone with a FOSTEX tech in Canada here-
he says you cannot get true phaze lock on a PC
when dumping over 8 tracks at a time via litepipe-he says its
because of inconsistencies in [a] the PC!"


You cant get a true phase lock on a PC? It has nothing to do with the PC but the clock being used. All clocks have imperfections which is why you do get jitter. Which is also why people spend thousands of dollars to buy nicer ones. So to say that it is a PC based problem i bull when its fully dependable on the clock of the sound card. Also, the number of tracks is really irrelevant. If it has clocking problems in the first place the clocking is going to be just as bad with 2 tracks as with 8. Although it might be more noticeable with 8. And overall, to be getting the effect that he is getting because of a bad clock, he must be using one horrible clock. A vibrato on the snare? Thats needs to be delayed by at least 40 milliseconds on some of those tracks at least. And pops and clicks from the clocks trying to sync would also be very very audible.

Which is why my theory is it is not clock related but monitor or loop related. It is something ive never even seen even when i dont have my computer and my HD24 sync locked together and pulling in 24 tracks.

Do you have any tracks armed so its picking up the snare twice maybe? Also, is this problem actually being recording or is it just on playback?

If it sounds like im dismissing a "pro" (or even possibly someone highered to read out of a notebook) thats not what im doing. His answer about the clock not being able to fully sync up is true. But what im questioning is whether he understand what the problem really is, which will be completely dependent on how john approached and communicated the problem to the tech. If he started the conversation with "Im having problems syncing my Fostex to my computer." Obviously the tech is going to reply with answers related to syncing problems. So a lack of communication could have been present. Not anyone fault just everyone has the wrong idea.

Danny

Danny
 
By the way Darnold -I think that warbly gurgly snare tale off I mentioned was someting to do with a stress on the ASIO -because I took out my 2nd graphics
card before my session yesterday[ just to be safe ]-and after doing some transfers I dont notice ant 'analmoties"...

if i can reproduce that wierd sound I will...just so you guys dont think Im nuts!

JF
 
No im convinced as long as you have fixed the problem. So i take it all went well then with it?

That would have been an IRQ conflict most likely. I forgot to explain what those were. IRQs are basically the addresses of your hardware. It is how your computer regcognizes where they are at. Everything including motherboard, harddrives, video cards, sound cards, network cards, keyboard, mouse is assigned an IRQ. The problem is your computer only has so many so it starts to share IRQ. Most things can share by taking turns because they dont need a full stream of data but audio is one thing that cannot. Most likely that extra video card had disrupted the IRQ table or it had been directly shared an IRQ with it. Both a sound card and a video card need a pretty constant stream so it could definately mess things up. Ive never heard about it doing something that strong but i guess if it loaded the system enough it would.

It would definately effect if the second card was PCI which im guessing it was. PCI is very effected by CPU and memory load in general, which is why they made AGP for video cards. It could have been general CPU load stress from the video card also.

Danny
 
Ya Dan-it was PCI and a real old ATI Mach 64 I had lying around.
However Im gonna try the Matrox G550 w/32 meg onboard RAM.
I need the extra moniters-hope that works.

I layed down claps/rim/spikes - whatever people prefer , on the FOSTEX 24 track-rite across all the tracks-so its gonna be easy for me to "sample align"
all the MTC drifted tracks-or at least calculate the offset.

However I dont feel quite as confident about getting a stand-alone
if I cant get the lock thing happening.Sometime im doing vey demamnding TV stuff .

Still considering going to more I/O soundcard kinda set-up.
{there is a certain confidence I get tho from the stand-alone-and there's
no "tweaky-tweaky...}

Any of you guys happy with the Ethernet option on the HD24?

JF
 
Im starting to get really confused with this whole thread :D.

I have been very happy with the HD24, but i havnt even used the Ethernet transfer yet, its always been too slow and the optical always works fine for me.

I just realized that Xstatic uses the Fostex 24 and uses it with the optical. Maybe you can shoot him an email or give him a call on the phone explaining the problem. Hes one those technical experts that i call whenever i need help (which probably bugs the hell out of him because i call him all the time :D) . I would just shoot him an email.

I guess im just confused as to what the problem is now. Is there a problem?

Danny
 
No- no problem.
I transfered 16 tracks - 8 at a time from the FOSTEX via 'optical'
into Logic Audio, I then sample aligned everything.

If it sounds like I'm complaining or himming & hawing its only because -
aligning everything in the computer "after" can be time consuming-a bit tricky...

SO..... I'd like to know that at least one of these stand alones recorders can transfer "wave" files painlessly thru Ethernet. [And im researching that point cuz i may buy the Alesis.]

anyhow thats regarding my last post when i said "how do yoe/anybody find the Ethernet transfer...etc."


Thanx for your patience.

JF
 
Oh i see. i was just starting to get confused on what we were discussing.

The Alesis has been one of the best things i have ever bought. The Converters in them are well worth it. And being able to do 24 channels portably is amazing also. Supposedly the converters in the HD24 are better than the Fostex 24 track also.

Like i said i dont really know about the Ethernet because i normally do all my recordings straight through the HD24 into the computer. Its basically used as a front end converter.

Danny
 
rite on track:
I suppose the thread title about jitter ties into whethter i should use optical-reliability-etc.-using stand-alone vs. PC -or both-ya know that whole
discusion.....on....on & on..... :)


thanx for the alesis review-hadnt heard any convertor comparisons till now.


jf
 
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