Cornford hurricane Blown Mains TX 2nd time

[J M Fahey]

Well, it *does* have a lot of gain with its 3 almost full throttle gain stages cascaded before the effects loop , plus a full gain stage after, , all of them before the tone control, so having hiss there and it being controled by the treble pot is not surprising.

Trying to filter it out would probably turn sound into mud.

[Mick Bailey]

If the customer likes the amp the way it is, then I'd be tempted to leave it alone. Reducing the gain of those stages may alter the dynamics of the amp to an unacceptable degree. At a push you could audition different makes/NOS tubes in V1 - sometimes you can drop on one that makes a difference to hiss, though in general it will be because it happens to be slightly lower gain.

Using a 12AT7 will give lower gain/lower hiss, thought I'd be tempted to also try this in V2 position. Removing the bypass cap on V1 will also reduce the gain. You can easily try them without materially changing the amp.

It all comes down to the expectation and playing style of the person using the amp.

[blindboybenton]

Hi all

Just had a email from the customer

He said the amp has never sounded so good !!

He has had it for about 1 week now. Im please its out of the workshop

I did in the end leave the amps hiss. It sounded alittle too much and i didnt remember hearing it when i first assessed it

Job closed!!

John

[Roosville]

As a future precaution, an amplifier like this needs to have a scope attached to see if it is oscillating at a very high frequency (>>20kHz).