[techguy0192]

I've got a new 2.5B3 that after existing the startup delay, the moment the LEDs go green there's a slight audible pop/snap sound through the speakers.  I thought all the new circuits would totally eliminate anything like this?

Yes, I know proper startup/shutdown sequences.  I have also tested turning on the amp without the preamp already on for testing, and get the same results.  My old SST2 amp would give an audible zip sound at turn off as the DC discharges, which was normal.  I assume this "new" sound with my cubed amp is OK, but just wanted to check in here.

[James Tanner]

I've got a new 2.5B3 that after existing the startup delay, the moment the LEDs go green there's a slight audible pop/snap sound through the speakers.  I thought all the new circuits would totally eliminate anything like this?

Yes, I know proper startup/shutdown sequences.  I have also tested turning on the amp without the preamp already on for testing, and get the same results.  My old SST2 amp would give an audible zip sound at turn off as the DC discharges, which was normal.  I assume this "new" sound with my cubed amp is OK, but just wanted to check in here.

Hi

I think Mike may be able to help with this.
mpickett@bryston.com

james

[schmidtmike76]

My 2.5 cubed does the same thing perfectly normal.  I was worried at first and Mike P calmed me

[techguy0192]

Thanks for the quick response, James. 

My 2.5 cubed does the same thing perfectly normal.  I was worried at first and Mike P calmed me

Thanks schmidtmike76, that's all I needed to know.  Did Mike provide any additional details?  I assume there's no ill effect on the speaker drivers; I assume you also had a similar concern.

[schmidtmike76]

No he didn't provide other than it should be silent.  I've heard two 2.5 cubed power on and they both do the same thing lights goes red...zzzzzz....little pop.  Nice description hey haha but that's how it goes down. 

[Will_PWR]

It might be speaker cable-related....

I have 2 sets of speaker cables that I've tried with my 4B Cubed.  Canare 4S11 bi-wired at the speaker end and a single-wire Belden 10 gauge, both from BlueJeansCable.

When using the Canare, I get the "pop" sound from my speakers on turn-on.
When using the Belden, silence.

I use the Belden.     It sounds better to me anyways.

[techguy0192]

It might be speaker cable-related....

I have 2 sets of speaker cables that I've tried with my 4B Cubed.  Canare 4S11 bi-wired at the speaker end and a single-wire Belden 10 gauge, both from BlueJeansCable.

When using the Canare, I get the "pop" sound from my speakers on turn-on.
When using the Belden, silence.

I use the Belden.     It sounds better to me anyways.

Very interesting as I'm also using the same Canare cable. 

I swapped in a really crappy pair of ultra cheap 14awg zip cord.  The turn on sound is still there; however, it is a little less dramatic in nature.  So, maybe this is in fact cable related.  The Belden is cheap enough to give it a try.
 

[srb]

It might have something to do with cable capacitance.  Given the three speaker cables discussed, the lower conductor to conductor capacitance does seem to follow the witnessed reduction in pop noise behavior on startup:

Canare 4S11             ~ 45pF/ft
14 AWG zipcord         ~ 34pF/ft
Belden 5T00UP          ~ 26pF/ft

Steve

[techguy0192]

Yes, there does appear to be a connection with the capacitance of the cables.  I also tried 10 awg zip cord and Anti-Cables, both in a shotgun configuration.  So far the Canare has been the worst offender.

This is odd because out of the many many amps I have owned, this has never come up.   Hopefully, I'll hear back from Mike when he returns from holiday. 

[techguy0192]

I tried a supper short run (~4ft) of 16AWG zip cord.  Still get the pop.  Oh well...I'll live with it and stop chasing cables to make it go away.     I sum it up as just being the opposite of the SST2 that did a similar thing at power off as the caps discharged.