My father-in-law was a meteorologist in the RAF back in the 50s. One day they were all sat around drinking tea because the RADAR equipment was out of action. An NCO got uppity with them and demanded to know what was wrong with it, and they told him they were waiting for a new magnetotron. He didn't believe there was such a thing, got angry with them for trying to make him look stupid and went off to report them to the CO. The CO told him that, no, there was a component called a magnetotron, and they were, indeed, waiting for a new one and he'd told the men to stand down until it arrived. After that they could tell him what they bloody well liked, because he wasn't about to make an idiot of himself by checking up on them again.
This is how I feel about the Gyrator.
I was playing my DSL40CR at home today, at low volume, and as I bent down to fiddle with the knobs, I heard a low rushing sound which sounded like the wind. I got on the floor and listened closely and it was, indeed, coming out of the amp. I hadn't heard this before so I decided to contact Marshall.
First of all, it's not as easy as it used to be. You used to call the switchboard and they'd put you through to the technical help guys, good solid guys with names like Mike and Gerry, who were only too happy to advise you about your amp, chat about the design philosopy and tell you yarns of rock star Marshall users of long ago.
Now you get a chat bot on the website.
Who promises to put you through to someone in technical support. Probably even if you ask it for an egg sandwich.
Me being me, I had the Marshall switchboard number saved in my phone, so I called them. They seemed confused that there was an actual person on the phone wanting to actually talk to someone and said I should email. I said that was sad, as I used to phone up and talk to the technical support line. I was told, "Oh, yes, he retired". After some more chat they did put me through to a guy in the service dpartment, who was very helpful and sent me an email to give him all the details, and I did get an email response quite quickly, to be fair. This is what it said (I've cut and pasted it out of the email, so any spelling mistakes are theirs, especially as I suspect they mean, "Gyrator," not, "Gryator.")
"Thank you for reaching out to us, with regards to your DSL40CR, the amplifier has a built in gryator to give a better bass response, this creates the low wind noise you can hear when the amplifier is sat idle, as long as it cannot be heard whilst playing then the unit isn`t faulty."
Now I feel like that RAF NCO. I feel like I'm being told there's something in my amp that I've never heard of and it sounds made up.
So, what is a gyrator (gryator?) please? And why is it a good thing?
Thanks, chaps
Comments
https://en.m.wikipedia.org/wiki/Gyrator
Often referred to as a 'Fan'...
https://youtu.be/L4MGG3kt5pY?si=OlTBf6qlGTCWZf0h
Didn't some overdrive/distortion pedals use a gyrator for an active bass control? Some of the Digitech ones, maybe the Hardwire OD/Distortion? Or the MXR Super Badass OD?
There was a batch of Chinese-made ECC83s about two/three years ago that were incredibly noisy because of poor manufacturing and zero audio QC checking at the factory. Whilst they were returned for destruction/credit by most of the major wholesalers/manufacturers, its highly likely that at least some will end up with the sales channel through another route. They'd probably be fine in a non-audio application, to be fair, but were unacceptably noisy in a guitar pre-amp.
Thanks
I suspect it probably is a dodgy valve, as @impmann said. Bit annoying as mine was brand new!