RE: [Harp-L] Fireball and Impedance Matching Transformers

["John Balding" <John.Balding@xxxxxxxxx>]

In a nutshell, true. All true.
 
However, with regards to:

"With a high impedance mic (exactly: with it's huge output) you'll
overdrive the first amplification stage, and that's very significant for
a particular sound."
>>>I think what you meant here was "drive the first amplification stage
HARDER", not necessarily overdrive it. If your mic was 100K ohms and
your amp was 1M, you would not overdrive it, per se. If your mic was 5M,
you would certainly overdrive it. The amount of drive on the first
stage, as you said, is definitely significant for a particular sound.

And:

"You may get the same volume, but you will not get the same sound."
>>>Absolutely. I guess what I should have said was "the same volume
level with similar tone". The distortion in this scenario would be
coming from the power tubes more than the preamp tubes. When I first
posted, I was thinking in terms of getting the most texture out of a Low
Z mic without using an impedance transformer. Given that the SM57,
Fireball, etc. will inherently give a cleaner tone to the first gain
stage, the distortion, or tube tone, will certainly come from the later
preamp section(s) and the power tube section. The idea was to extract
the most grit out of an otherwise potentially clean setup. Since a lot
of harp players use low-gain tubes in the preamp section already, I
suggested using high-gain tubes with Low Z mics, as the high-gain tubes
would tend to drive each successive stage harder, creating a more
textured tone. The same concept comes into play with the traditional
vintage mic setup as well. Changing the preamp tubes to reduce
gain/feedback also alters the tone to some degree. But we live with that
because it is sometimes the only means to an end. My postulate was made
based on the idea that it was possible to play a Low Z mic into an amp
safely with acceptable results. Perhaps not the tone of an old bullet
mic, but certainly much more growl than running through a P.A.

After all is said and done, the Fireball seems that it offers a wide
range of tonal palettes to choose from; depending on the equipment it is
run through. Most traditional harp mics cannot offer that broad a range,
due to their inherent design characteristics. As a Blues player, I never
even gave the Fireball a second glance. But after all of the discussion
on the list, I'm beginning to get the feeling that I might like it...

Thank you for your gracious rebuttal,

John


-----Original Message-----
From: harp-l-bounces@xxxxxxxxxx [mailto:harp-l-bounces@xxxxxxxxxx] On
Behalf Of Ralf K. Buschner
Sent: Wednesday, August 23, 2006 8:34 PM
To: harp-l@xxxxxxxxxx
Subject: Re: [Harp-L] Fireball and Impedance Matching Transformers

John Balding wrote:

> Without the transformer, the amp would have to be played at 6 or 7 to 
> obtain the same volume level and tone.

Sorry, but i can't agree here. The usual guitar amp is build like that:

input jack   //    first tube system   //   volume pot   //  further
stages 
and tone stack //  phase inverter  //  final stage   //   speaker.

With a high impedance mic (exactly: with it's huge output) you'll
overdrive the first amplification stage, and that's very significant for
a particular sound. If a mic gives lower output to the 1st stage, you
can compensate the volume issue by cranking the amp up, but since that
low signal amplitude from that mic won't make the 1st tube system
distort, the signal "arriving" at the volume pot is much, much cleaner
than if you would use a high Z high output harp mic - and therefore is
the whole sound chain very different. You may get the same volume, but
you will not get the same sound.

Take a guitar, plug in, turn the volume knob on the guitar way back and
the volume on your amp up. Clean, loud. 
Now turn the vol on the guitar all the way up, and take the amps volume
back, so that you get the same volume over all. Distorted, loud.
With one exception: You have an amp, which stays clean at all.

cu,
Ralf
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