My Ultimate Harp Amp (very long)

[wmharps@xxxxxxxxx]

Some who have been around this list for a while may recall that some years ago 
I embarked on a mission to build my ultimate harp amp.  After more than six 
years and much on-again/off-again working on it, I finally have it "finished".  
I am very pleased with the results, just thought I'd share my experience.  

The idea was to build a combo amp that consisted of rack components mounted in 
a cabinet housing the speakers.  I chose a PAiA TubeHead tube preamp (built 
from a kit), an Alesis Midiverb 4 effects processor, and a Rolls RA235 power 
amplifier.  All this stuff is housed in a finger-jointed pine cabinet 
containing two WeberVST P10Qs.  

The preamp has both solid state and tube input stages, with a dialable "Blend" 
control to set the amount of tube compression, allowing settings from 
completely clean to totally compressed and crunchy.  The two-channels are 
independently configurable, and outputs feed the Midiverb.  Some suggested that 
I feed the signal first into the midiverb and then into the preamp, but I have 
found that the signal is cleaner this way.  I speculate that the digital 
effects unit is better able to handle the frequency range of the preamp than 
vice-versa.  

The Midiverb offers a huge spectrum of digital effects, though I use it mostly 
for reverb (I have been known to use the octaver!).  There are 128 presets and 
another 128 user configurations, so I can customize the effects I want for harp 
(which usually amounts to turning them down!) and store them permanently.  The 
Midiverb also has input and output level controls, and I added a footswitch for 
on-stage bypass of the effects.  

The Rolls amplifier is 35 watts per side, stereo, solid state, with volume 
controls for each channel.  It is bridgable to mono, which is the way I 
normally run it, though it would be possible to set the amplifier up for two 
completely discrete signal paths, so one could be configured, say, for vocals, 
the other for harp.  My original Rolls amplifier overheated and burned out, 
taking out one of the Webers in the process, but the new one has much better 
heat sinking (the channel volume controls are also new).  Weber made me a great 
deal on reconing my burned out P10Q.

The cabinet houses the two Webers below the rack mount area in about the same 
size as a Fender Vibrolux.  Inside the cabinet as well is a surge protected 
power strip for the components, and a Sennheiser E604 drum mic mounted on a 
gooseneck and wired to an XLR connector in the side, so remicing the amp 
through a PA means running a standard mic cable from the amp and plugging it 
in.  I also mounted the handle on the side to leave the top clear, and put the 
casters on the opposite side.  

The result is wonderful.  I can set tone and effects and volume all 
independently from each other.  Using a combination of preamp solid state/tube 
blend and overdrive I can get a huge range of tonal colorations, and even more 
by selecting different microphones.  I can use the Midiverb to add reverb, 
echo, chorus, flange, and pitch effects, and can even split the two sides into 
dual mono to run separate effects for each channel.  And then I can set the 
volume level where I want it, I don't have to crank it to a certain volume to 
get the tone I want, or swap power tubes to get the right amount of compression 
in the amplifier.  

I'm going to try to record and post some sound samples and also post some 
pictures of the amp in the near future.  In the end it wasn't cheap -- I 
probably could have bought a nice vintage tube amp for less -- but it is all 
the amps I will ever need from the studio to the stage, and I couldn't be 
happier with it!

- -tim