Zinky Superfly blog - Part 22: Full Costs At Last?

Finally some costs for the amp shell...

However there's a little doubt there as to whether there is one available quite as easily as I'd expected, considering that the Superfly was/is still advertised as being in production.

Also, I shouldn't need another reverb pan - I've already got two which work as well as each other!

Finally some thoughts on biasing that rather went over my head. $60 for a new set of power tubes should sort things out though. I hastened to respond - see part 23.

From: zinky@zinky.com
Subject: Re: Shipping Superfly chassis
Date: 16 April 2008 18:53:21 BST
To: david@dave.st

Hello David;

It's going to be $100 for the reverb fix, plus power supply and other updates. No tubes necessary there, but
if in doubt, you should have a spare set of output tubes. That way, if there's ever a question, you just replace the
tubes, give it a listen, and if the sound improves, buy a new set of spares.

What I was wondering was the price quoted on the cabinet. I may still have one new one in black, but what I might have to do would be to uncover a silver cabinet and re-cover it in black...That's a whole lot of work to clean off the old glue. You have to rid yourself of the old glue if you want the vinyl to sit flat on the cabinet, without lumps. That would run $250 for the raw cabinet, and $290 assembled (with new reverb pan, logo, your choice of Black or Cream grille cloth), as the transformers get braced against the pan and the cabinet to reduce chassis damage in shipping.

Tubes- We sell burned in, tested, graded and matched sets for $60. No biasing necessary, just plug them in and go. We found that carefully selecting the tubes yields much better reliability and consistency. Another benefit is that you can just plug in the new tubes without worrying about bias.

Truthfully, bias refers to the idle current of a tube, no signal. You can do it yourself with a voltmeter and your EARS more accurately than anyone using a 'scope (Testing the response of a sine wave on a guitar amplifier is meaningless) or other paraphernalia.