DC Speaker Protection - Guardian 86

[John Berard]

Just curious if anyone has implemented these boards into their amp builds.

Guardian-86

The Guardian-86 is a high-end solid state speaker protection circuit board module for use in audiophile audio amplifiers. The Guardian-86 uses MOSFETs instead of relays to protect your speakers resulting in better performance and better protection of your speakers.

neurochrome.com

 

[peterh]

Just curious if anyone has implemented these boards into their amp builds.

Guardian-86

The Guardian-86 is a high-end solid state speaker protection circuit board module for use in audiophile audio amplifiers. The Guardian-86 uses MOSFETs instead of relays to protect your speakers resulting in better performance and better protection of your speakers.

neurochrome.com

Breaking output on a tubeamp might cause damage to the amp. The above device seems unsuitable for use with a tubeamp.

 

[John Berard]

Breaking output on a tubeamp might cause damage to the amp. The above device seems unsuitable for use with a tubeamp.

The OPT would have already failed for excess DC current to flow, right? I could see additional damage to tubes however. What came first, the blown amp or the blown speakers? I would at least try to save my expensive speakers. Any other approach for a good solution is welcome.

 

[gadget73]

yeah, the output transformer would have to short, and even then it wouldn't typically dump any significant DC to the speakers if its a feedback amp, or just one built in a normal way. One end of the speaker secondary is grounded, so a short from the high voltage to the speaker secondary just dumps that voltage to ground until something blows and cuts the power. Hopefully the fuse, but it could be a transformer winding or a resistor. Unlikely to be a speaker secondary winding though, those are much heavier wire than the primary.

so just to rephrase what peterh said, I don't really think this is a solution to any problem you are likely to encounter.

Unless you're talking about an output transformerless amplifier. I could possibly see justification there. Or on an amp where the speaker side is not tied to ground, but I'd probably just fix that by adding a ground connection.

 

[maxhifi]

Normal tube amps are incapable of putting DC on the output due to the transformer coupling. That device is intended for solid state amps.

Actually one of the things I like about moderately sized tube amplifiers is they are much less likely to damage speakers than a big solid state amp.

 

[John Berard]

Thanks everyone for your input!