• Welcome to the Pipe Organ Forum! This is a part of the open community Magle International Music Forums focused on pipe organs (also known as "church organs"), organists, organ music and related topics.

    This forum is intended to be a friendly place where technically advanced organists and beginners (or even non-organists) can feel comfortable having discussions and asking questions. We learn by reading and asking questions, and it is hoped that the beginners (or non-organists) will feel free to ask even the simplest questions, and that the more advanced organists will patiently answer these questions. On the other hand, we encourage complex, technical discussions of technique, music, organ-building, etc. The opinions and observations of a diverse group of people from around the world should prove to be interesting and stimulating to all of us.

    As pipe organ discussions can sometimes become lively, it should be pointed out that this is an open forum. Statements made here are the opinion of the poster, and not necessarily that of the forum itself, its administrator, or its moderators.

    In order to post a new topic - or reply to existing ones - you may join and become a member by clicking on Register New User. It's completely free and only requires a working email address (in order to confirm your registration - it will never be given away!). We strive to make this a friendly and informative forum for anyone interested in pipe organs and organ music.

    (Note: If you wish to link to and promote your own website please read this thread first.)

    Many kind regards
    smile.gif

    Frederik Magle
    Administrator

    Krummhorn
    Co-Administrator

GO and reverb

erikds

New member
I have experienced a relatively large latency with reverb when first starting GrandOrgue, but this can be fixed by changing the audio settings in (seemingly) any way. Once reverb has been turned off and back on again, a new IR file has been chosen, dirac pulse adjusted, pressing the "panic" button etc. the latency problem is solved.
Click to expand...

wehtam721 said:
I'm attaching a pdf document here to show the audio settings panes in GrandOrgue. I took screen shots of the panes.

I have downloaded and installed the latest build for windows (rev 1178) and can confirm that the same problem occurs when first launching this new version of GrandOrgue as well. I have been able to replicate it many times. As I mentioned in my previous post about this, changing any of the audio settings (including settings other than those on the reverb panel) will solve this problem until GrandOrgue is closed completely and opened again.

Matt
Click to expand...

I have the same or at least a similar experience.

Attached are the screen shots of my settings.

What i have is:

About half a second delay between pressing a key and sound.
Very distorded sound but only from notes played on middle keyboard, not on other ones.
This happens only immediately after loading a disposition; pressing e.g. panic button removes any problem.

This is on Windows 7 64 bit system, 8Gb Ram, Q6600 quadcore, Focusrite Saffire sound card using its WDMKS/WASAPI driver.

Anything in addition helpfull to pinpoint cause of the problem?

All the best.

Erik.

View attachment GO-latency.zip
 

wehtam721

New member
To compare with what Erik described:

I also experience a delay of about a half of a second, but I'm not experiencing the distorted sound that he describes. The output sounds correct over the entire scope of the keyboard and pedalboard, just delayed.

I am also running 64 bit windows 7 system with 8Gb of ram. Intel cork i5 processor. Sound card info can be seen in the screenshots posted above.

Take care,
Matt

P.S. After some further experimentation, I can also say the following. After loading GrandOrgue and pressing the panic button to correct the sound, I have exported a settings file. Then closing GrandOrgue completely, reloading the organ (testing to be sure that the delay is still happening), then importing the settings file for the organ will also fix the latency issue, so it would seem that the value which is causing the problem is stored in the .cmb file. That, or loading the settings from a .cmb file causes the same audio reset as pressing the panic button or changing any of the other settings. If the latter is true, this probably isn't too helpful, but if the former is true, I figure this may be very helpful.

P.P.S. After creating a settings file before pressing panic and settings file after pressing panic and running them through an online compare test to find any differences, they files are shown to be identical, so it looks like importing settings is just resetting the audio and that the value causing the problem wouldn't be stored in the .cmb file.
 
Last edited:

e9925248

New member
@erikds:
Your setup is totally different. You are using the multi-soundcard support - this feature is currently not supported, as there are still synchronization issues, that you notice.

@wehtam712:
In my option, it is most likely a sound driver issue: Panic or (re-)loading closes the sound interface and reopens it. The parameters stay exactly the same - unless you changed something in to GO audio config. Therefore I would first look for a sound driver update.
To eliminate a portaudio wdk-ks bug as cause, you could try the other sound output methods in GO, if they show a similar behaviour.
 

erikds

New member
e9925248 said:
@erikds:
Your setup is totally different. You are using the multi-soundcard support - this feature is currently not supported, as there are still synchronization issues, that you notice.
Click to expand...

I use only a single sound card, the Focusrite Saffire.

Is using a (single) multichannel sound card (8 analog and 2 digital channels in my case) not supported?

If so, what is the meaning of providing the possibility under Midi & Audio Settings / Audio Output to "Add" devices?

All the best.

Erik.
 

e9925248

New member
erikds said:
Is using a (single) multichannel sound card (8 analog and 2 digital channels in my case) not supported?

If so, what is the meaning of providing the possibility under Midi & Audio Settings / Audio Output to "Add" devices?
Click to expand...

In your setup, your sound card driver provides three distinct sound outputs a 2 channels instead of one with 6 channels [Maybe this is configureable in your sound driver?]

Initial code for such setups is present in GO - it may work (with some problems) or not. It is not a well supported, stable feature.

GO officially supports only one sound output with any number of channels (like Lars screencasts showed). This is even supported by the cheapest onboard sound cards.
 

JLD

New member
not directly related to post
I use only a single sound card, the Focusrite Saffire.
Click to expand...
I was looking at the Saffire interfaces mainly for recording since I have heard the preamps are very good. Have you done any recording?

Thanks,
JL
 

wehtam721

New member
e9925248 said:
To eliminate a portaudio wdk-ks bug as cause, you could try the other sound output methods in GO, if they show a similar behaviour.
Click to expand...

I have tried the other sound output methods available to the sound card and all options experience the same problem, so it doesn't seem to be a portaudio wdm-ks bug. I tried, however, turning off reverb, closing GrandOrgue and reloading it (so that reverb would be disabled at start up). Sound plays back instantaneously without the latency issue I've been describing. Re-enable reverb, close GrandOrgue, open again, latency is back. It seems that the problem I'm experiencing is, in some way, related to the reverb functionality.

@erikds: Have you tried reloading GrandOrgue without reverb? If so, do you still have the latency issue when GrandOrgue is loaded without reverb?


Additionally, (and I don't know if this is related or not but) switching between sound outputs is now causing GrandOrgue to crash. I haven't had this problem with previous revisions, and this is happening regardless of whether reverb is on or off. After the crash, opening GrandOrgue works fine and it loads the output that I had selected before the crash without a problem. The crash happens when pushing the "OK" button on the settings window. GrandOrgue is hanging there. The settings window doesn't close before the crash.

Lastly, searching for updated drivers yields that the most recent drivers are already installed, but I'll continue to look into this.

I hope that this helps,
Matt
 
Last edited:

e9925248

New member
wehtam721 said:
I tried, however, turning off reverb, closing GrandOrgue and reloading it (so that reverb would be disabled at start up). Sound plays back instantaneously without the latency issue I've been describing. Re-enable reverb, close GrandOrgue, open again, latency is back. It seems that the problem I'm experiencing is, in some way, related to the reverb functionality.
Click to expand...

Strange. I'll try to reproduce it.

wehtam721 said:
Additionally, (and I don't know if this is related or not but) switching between sound outputs is now causing GrandOrgue to crash. I haven't had this problem with previous revisions, and this is happening regardless of whether reverb is on or off. After the crash, opening GrandOrgue works fine and it loads the output that I had selected before the crash without a problem. The crash happens when pushing the "OK" button on the settings window. GrandOrgue is hanging there. The settings window doesn't close before the crash.
Click to expand...

Is this related to switchting between specific audio output entries?
 

erikds

New member
JLD said:
not directly related to post

I was looking at the Saffire interfaces mainly for recording since I have heard the preamps are very good. Have you done any recording?

Thanks,
JL
Click to expand...

I know that the Focusrite Saffire's preamps have a good reputation, but i am not into recording and therefore have no personal experience about it.

The Focusrite Saffire model is now "a discontinued product" as they call it at Focusrite.
I asked them if it would work under Windows 8.

This was their aswer:

The orignal Saffire's are not currently part of our testing plan as they are a discontinued product, but there is no reason why they would not work. However, if there were any issues there will not be any software updates to resolve them.

All the best.

Erik.
 
Last edited:

erikds

New member
e9925248 said:
In your setup, your sound card driver provides three distinct sound outputs a 2 channels instead of one with 6 channels [Maybe this is configureable in your sound driver?]

Initial code for such setups is present in GO - it may work (with some problems) or not. It is not a well supported, stable feature.

GO officially supports only one sound output with any number of channels (like Lars screencasts showed). This is even supported by the cheapest onboard sound cards.
Click to expand...


Saffire audio outputs.PNG

As you can see in the picture, the Focusrite Saffire can be configured any way you want. In essence it gives 8 independant analogue mono channels an 2 digital ones.
It offers a choice of drivers as you can see.
What i did, using the Pitea disposition as example, was:
- define 3 audio groups namely Front, Side, Bass
- direct audio ouput of windchest 1 (pedal) to Bass, winchest 2 and 4 (great and brustwerk) to Front and windchest 3 (swell) to Side using each time a Left and a Right channel.

With your remark above, do you mean that using more than 2 mono channels in total is not well supported at the moment?

If so, does this mean that the features Create audio groups and the possibility to allocate per rank its belonging to an audio group is "experimental"?

All the best.

Erik.
 

erikds

New member
wehtam721 said:
I tried, however, turning off reverb, closing GrandOrgue and reloading it (so that reverb would be disabled at start up). Sound plays back instantaneously without the latency issue I've been describing. Re-enable reverb, close GrandOrgue, open again, latency is back. It seems that the problem I'm experiencing is, in some way, related to the reverb functionality.

@erikds: Have you tried reloading GrandOrgue without reverb? If so, do you still have the latency issue when GrandOrgue is loaded without reverb?

Matt
Click to expand...

Hello Matt,

I confirm your findings; when loading GrandOrgue with reverb disabled and then loading a disposition (Pitea in my case) there is no latency problem.
When loading GrandOrgue with reverb enabled and then loading the same disposition, the latency problem comes back.

All the best.

Erik.
 

scush

New member
This problem is affected by the length of the impulse file.
I started with a file of approx 3 seconds long, this gave an initial latency of 200ms
I then added 10 seconds of silence to this file in a wave editor, the same file now loads correctly.
After this I added 2 more seconds to confirm things, there is still low latency however some artifacts can now be heard
So for now it looks as if the I.R. files have to be adjusted to be compatible with GO.
 

scush

New member
yes

I haven't tried playing with it yet, but it seems ok on the laptop.

10 seconds was just something to try, many things will have to be tried out to understand this


john
 
Last edited:

e9925248

New member
@erikds:
Have you watched Lars screen cast about multi channel audio?
GO would support a configuration with one sound card entry with 6 output channels (similar to the config, Lars showed). Anything with more than one sond card entry is experimental, so eg: 3 sound card entries a 2 channels as you configured.

PS: During further research I noticed some strange reverb behaviour. Need to do further research, which will take some time.
 

erikds

New member
e9925248 said:
@erikds:
Have you watched Lars screen cast about multi channel audio?
GO would support a configuration with one sound card entry with 6 output channels (similar to the config, Lars showed). Anything with more than one sond card entry is experimental, so eg: 3 sound card entries a 2 channels as you configured.

PS: During further research I noticed some strange reverb behaviour. Need to do further research, which will take some time.
Click to expand...

I have finally understood that using the WDMKS driver each pair of sound channels is seen as a separate device.
Using a ASIO driver this is avoided.
I modified my setup accordingly. See picture below.

I reconfirm that immediately after startup of GO and loading of Pitea dispo there is quite some latency.
Clicking the panic button eliminates this, as in previous tests. From then on GO plays very nicely.
Reverb works without problem if buffer size is equal to 2^n. Otherwise an error is shown and it is disabled, but the mark "enabled" in the reverb pane remains set.

All the best.

Erik.

GO-latency-1div-6ch.PNG
 
Last edited:

scush

New member
The Epinette Harpsichord is a good set to test with it loads fast, and any latency easy to detect.
It also sounds great with reverb, even the key actions.
 
Last edited:

scush

New member
Hi.
The samplerate of the I.R.file has a big influence here.
I first made the impulse file to 131072 samples long. (^2)
Then converted it to different sample rates.
I then discovered the ratio between the samples per buffer setting and the sample rate of the of the I.R file, effect the latency after loading.
With a Samples per buffer setting of 512 And a samplerate of 192000 for the I.R file or 1024/96000
GO then loads without much latency, hardly any when reloaded.
 
Last edited:
You must log in or register to reply here.
Top