Hiss from surround channels?

Jason Nugent · « **on:** 21 May 2006, 04:44 am »

James,

Finally put the SP2 and the 9B/4B into their respective places and watched a couple of movies. I was wondering how much background hiss was normal with a standard movie sound track. There seems to be certain modes with the SP2 that generate a lot of hiss in my rear surround channels. For instance, watching a movie tonight with a Dolby Digital soundtrack generated enough hiss in my rear left surround channel that I could hear it over the dialogue in the film. When I switched to listening to a CD in PLII+THX, which put information in that same speaker, there was no issue. The wierd thing is that it doesn't happen all the time. Just before writing this, I was able to make it hiss-free by restarting the SP2 and my DVD player.

I've never had hiss in any of my surround channels with my old receiver.

Have there been any firmware updates for the SP2 that might relate to this sort of thing? I'm running the original Dec 1, 2005 firmware version.

Thanks,

Jason

Levi · « **Reply #1 on:** 21 May 2006, 05:08 am »

Something does not sound right with your SP2. The reason I switched to Bryston ultimately to it's low background noise. Definitely, there is the need to identify the source of the noise as this can be very distracting. Sorry to hear about the problem as I don't think a firmware upgrade can fix that.

Jason Nugent · « **Reply #2 on:** 21 May 2006, 03:36 pm »

Here's another bit of weirdness. I have two back surround channels, configured to run off of the same 9B channel (so, a 6.1 config with two identical rear channels). Works great. I'm using the back left surround RCA output to do this, since I have my back speakers configured as SMALL1. But, when the SP2 is on and my 9B is on, but my DVD player is off, I get a very quiet "beep beep beep beep" from those two speakers. When the DVD player is turned on, even if it's not playing anything, the noise goes away, and it sounds fine during movies.

Really strange.

Jason Nugent · « **Reply #3 on:** 21 May 2006, 04:59 pm »

Quote from: Levi

Something does not sound right with your SP2. The reason I switched to Bryston ultimately to it's low background noise. Definitely, there is the need to identify the source of the noise as this can be very distracting. Sorry to hear about the problem as I don't think a firmware upgrade can fix that.

Yeah, it's really bizarre. There are a few things I want to try to narrow it down. I doubt it's a physical connection because I can make the hiss go away at will by just switching my source to CD or changing the mode I'm listening to. If I get hiss again, I'm going to try swapping the XLR inputs for my surround channels to see if I can move the hiss to another speaker. If it stays in the same speaker, it's probably the channel on the 9B. If it moves to the new one, it's probably the SP2.

Jason Nugent · « **Reply #4 on:** 22 May 2006, 03:06 am »

An update. My wife wanted to watch a movie tonight (Harry Potter and the Goblet of Fire), so we popped it in. I ended up with hiss from both left and right surround channels (but no hiss from the back). I tried tweaking the mode from the SP2 front panel, and I managed to eliminate the hiss two ways:

1. I swapped in my really old Panasonic A110 DVD player. No hiss.
2. With my current player, I cycled through the Bypass modes. Switched to 2 channel bypass, then to the 5.1 analogue bypass, and then off again. When it switched off, I got back to the movie soundtrack with no hiss.

Jason Nugent · « **Reply #5 on:** 22 May 2006, 04:31 pm »

I can now confirm that cycling through the bypass modes removes the hiss from my surround channels. This morning, I was doing some CD listening and when I switched to the CD (via analog inputs), I had hiss in all of my channels. Cycling through the bypass modes removed it.

I can live with this, but I'm not sure if it's "normal".

Mike Pickett · « **Reply #6 on:** 25 May 2006, 05:57 pm »

Hi Jason;

This sounds like an issue that would be solved by updating the main control software. A version that will correct this may be downloaded from our website, although we've finished beta testing a newer version, and should have that posted within a couple of days.

Thanks,

Mike

Levi · « **Reply #7 on:** 25 May 2006, 06:18 pm »

I hope the it works. Let us know the result.

Jason Nugent · « **Reply #8 on:** 26 May 2006, 11:39 am »

Thanks, Mike, I'll give it a shot.

Jason Nugent · « **Reply #9 on:** 20 Jun 2006, 11:59 am »

Quote from: Mike Pickett

Hi Jason;

This sounds like an issue that would be solved by updating the main control software. A version that will correct this may be downloaded from our website, although we've finished beta testing a newer version, and should have that posted within a couple of days.

Thanks,

Mike

Mike, just curious if the new version was ready to go. I've been periodically checking the website over the last few weeks and the version on the website is still at version 19.

No big deal or anything - cycling through the bypass modes always removes the hiss if there is any.

One other thing - for the first time, the SP2 didn't initialize all the way the other night. I turned it on, it started it's boot process, and never made it to the "DSP Ok" stage. It eventually said "DSP Err" or something like that, and I had to cycle the power again. Came up fine the second time.

Seeing as how I'm still using the original firmware, I suspect that this may also be something that goes away if I upgrade.

sikoniko · « **Reply #10 on:** 20 Jun 2006, 01:12 pm »

I dont see a "downloads" section on the bryston website. where would one go to download this when it does become available?

Jason Nugent · « **Reply #11 on:** 20 Jun 2006, 01:40 pm »

If you go to the technical page there's a drop down box for the SP2. One of the items is called "Firmware Update" and the downloadable PDF has the firmware update attached to it.