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Loopback Test - Printable Version

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Loopback Test - RichardRKenyon@msn.com - 05-11-2020

I'm a JB newbie trying to make the initial latency test using a Behringer UM2 interface. To make the loopback test do I need to plug a cable between the headphone jack and the Inst2 jack? I'm using a condenser mic input. Behringer suggests an ASIO4ALL driver for their UM2.


RE: Loopback Test - Ian (France) - 05-12-2020

newbie too, and I'm where you are !
yes, I believe that is how to set up the loopback test.... I have found that the loopback test won't start, or when it starts (once) it won't stop !
I've noticed I've got some blinking indicators on the behringer which I don't like and which seem to be caused by my rattling hard disk (internet background noise I suppose).... I'm going to try this again on another computer.... but I'll be interested in any replies in the meantime Wink

(05-12-2020, 04:32 PM)IanĀ (France) Wrote: newbie too, and I'm where you are !
yes, I believe that is how to set up the loopback test.... I have found that the loopback test won't start, or when it starts (once) it won't stop !
I've noticed I've got some blinking indicators on the behringer which I don't like and which seem to be caused by my rattling hard disk (internet background noise I suppose).... I'm going to try this again on another computer.... but I'll be interested in any replies in the meantime Wink
In fact, you don't have a problem? you just want confirmation?
If you do have a problem another thread has indicated that the driver can be problematic, and also that the loopback test can be temperamental, if I understand aright.


RE: Loopback Test - Ian (France) - 05-12-2020

more on the loopback test......

I'm trying to get the audio gear settings right using the test and it seems to me that the "device settings" in jkz don't help much, most are "recommended" anyway, so I'm resorting to twiddling the knobs on the audio interface box itself, and in very random fa$on, which seems to alter the results but difficult to see any logic .....
in any case, the results (latency and i/o) seem to want to vary of their own accord !
all of which is difficult to discuss, so here is a specific question:

why do a get 1000ms latency (no sound) having immediately before (no twiddling) obtained some sort of meaningful result? I think I would at least like to fix that - or I should fix that if I'm going to get anywhere !

supplementary question: when I did manage to get a double "fair" result (latency and i/o) and then tried a solo session, my latency showed up a good deal worse - normal?

if anyone has had any sort of experience of these two events then any pointers would be welcome, many thanks.


RE: Loopback Test - Ian (France) - 05-13-2020

I think what Richard is referring to is shown in the demonstration video for the loopback test and we see the jack is clearly taken off the guitar and inserted into the socket from which the headphone jack had just previously been removed - result, instrument input socket connected to mic output socket, hence loop....

but what I am taking away from your remarks is that the loopback test is probably more trouble than it is worth and the only testing worth doing is in a personal test session - which reassures me for one as I have struggled mightly with the loopback test, getting inpredicable/unuseable results which don't correspond with the results of the test session.

can you give us some detail on the WDM driver? this seems to be a generic term, thanks

(05-13-2020, 08:04 AM)IanĀ (France) Wrote: I think what Richard is referring to is shown in the demonstration video for the loopback test and we see the jack is clearly taken off the guitar and inserted into the socket from which the headphone jack had just previously been removed - result, instrument input socket connected to mic output socket, hence loop....

but what I am taking away from your remarks is that the loopback test is probably more trouble than it is worth and the only testing worth doing is in a personal test session - which reassures me for one as I have struggled mightly with the loopback test, getting inpredicable/unuseable results which don't correspond with the results of the test session.

can you give us some detail on the WDM driver? this seems to be a generic term, thanks

... and regarding testing when not in a session, this may explain my (occasional but frequent) 1000ms latency result in the looptest ("no sound") ! but that is quite puzzling, why give demonstrations/explanations which have no sense?

and as for the ping test, this is to test network latency isn't it? here we are interested in audio gear latency.... I think


RE: Loopback Test - bullmoon - 05-13-2020

The best way to get low latency is to 1) set your audio interface buffers as low as will work - 48 samples or lower if you can, and 2) set your Audio FrameSize to 2.5ms - do this in JK Manage/Audio Settings/Audio Booster. You'll have to be in a session to do this - Quick Start Solo session is handy for that stuff.

For the UM2 setup check these videos which also show where to get ASIO drivers.

https://youtu.be/xWirJwKyFx0
https://youtu.be/S3QHbhtknH8