Re: [Harp-L] Re: Mission amp and Copper plug ins

[Rick Davis <bluesharpamps@xxxxxxxxx>]

That is exactly right.  There is a subtle yet noticeable difference between
the sounds of a GZ34 recto and a SS W34 recto.

It is a matter of taste, and I have said.  Some players prefer the crisper
tone of the SS recto.  It cleans up muddy amps a bit and makes them seem to
project.  Other people prefer the tube recto.  It provides more sag and a
tiny bit of compression.  It sounds more like the vintage tones from Little
Walter and others, since they used tube rectifiers.

I have tried the copper plug-in SS rectifiers in many amps, from barky
little Champs to vintage Mascos to powerful custom harp amps.  I love the
tone in smaller amps, but in amps that have sag the SS rectos lessen it a
bit and make the amp sound tighter.  As I say, some people prefer that
texture.

Judging from some of the discussion here, I'm not sure that everyone
understands what sag in a harp amp is.  The rectifier in a vintage style
tube amp converts AC power to DC, which the rest of the components in the
amp need.  In amps that were popular with harp players in the Fifties these
rectifiers would sometimes lag just a bit when supplying power for a big
note.  The affect is that the note was not "crisp"... the leading edge of
the note -- the attack -- was attenuated.  It made the tone warmer, darker.
This effect was not linear... It did not sound the same at all volumes and
all intensities.  The player could manipulate the effect with his playing
and mic technique.

Players thought the sound was so cool they started modifying their amps to
enhance it.  Early Bassman amps had two rectifier tubes, and it was common
for harp players to remove one of the tubes to increase sag.

Here is a website with lots of good info about tube vs solid state
rectifiers:

http://www.guitaramplifierblueprinting.com/rectifiers.html

It seems to be two different tonal philosophies.  I don't mean to suggest
that one philosophy is "right" and the other is "wrong."  But they are
different and the tonal distinctions are evident.  Here is a comparison
which I think illustrates that:

http://bluesharpamps.blogspot.com/2010/07/comparison-mission-chicago-amp-vs-sonny.html


-- 
-Rick Davis
The Blues Harp Amps Blog
http://www.bluesharpamps.blogspot.com/




On Sun, Dec 12, 2010 at 7:46 AM, Michael Easton <diachrome@xxxxxxxxxxx>wrote:

> Gary gives us Avenger owners both the copper plug in and the tube
> rectifier.
>
> I was amazed at the subtle yet noticeable underlining difference between
> the two.  The Avenger came with the Copper installed.
>
> I tried that for a few days then tried the tube rectifier.  I switched back
> to the copper because I could get cleaner separation of the eq's.
>
> I think the  noticeable difference to my ears is the cooper tube tends to
> keep the eq's separated more whereas the glass tube tends to allow some
> bottom to bleed into the mids and highs almost acting
> like a filter.  I guess it didn't matter much when the bass, treble and
> mids were controlled by one knob on vintage amps.
> Now that separating the tone controls are the norm adding the tube
> rectifier can allow you to dial in more like a single tone knob where there
> is always some
> bottom or "warmth"  in the mix.
>
> Mike
>
>
>
>