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Piece Of The Week #7 - Uncle Spot 3-Knob Stand-alone Spring Reverb 

Uncle Spot 3 Knob Stand-alone Spring Reverb 

Ok, up to bat is a 3-knob reverb, but this one happens to be batting cleanup! I
have a good deal of experience with spring reverb. Spring reverbs that I've
owned include the Matchless, Kendrick, Diaz, Fender, Hoffman, Accutronics
Stereo Spring, Furman, Orban, and Clark. One of my all time favorite
stand-alone reverbs was my Maz 38 converted to a 1-12 reverb generator
(patterned after the Holland Stand Alone Reverb Amp with speaker)....100%
pure wet reverb and no dry signal! I would set it up on an A/B/Both box and
when I needed verb I'd activate the Maz 38 which would generate gobs of
reverb and put it into the room via it own 12" speaker. Full EQ controls, and
even a master volume and presence to adjust how dirty or crisp I wanted it!
Totally overboard, but cool. I converted it back to a regular amp and I can tell
the amp is much happier. 

Anyway, I hope that info sets the stage as far as what I've heard, used and
tried. I love reverb as an effect. I like hearing a healthy dose on a clean strat
for that Magic Sam sound. I like a little to add a little ambience in a real dry
setting. And I like the sound of spring reverb... digital doesn't do it for me on
live guitar sounds. 

The first thing I do with any reverb is first test the dry signal. The dry signal
has to pass through with excellent quality and a pristine and faithfull output
when compared to the input. This is absolutely paramount IMO and
unfortunately this is where they all fail. Every one of them roll off too much
top end IMO. I don't like that, I know some say "That warmth is whats so
cool", but me I just say its hi end roll off..... I prefer to keep my sparkle thanx.
Now keep in mind that these tube reverb heads process the dry signal through
tube stages.... so maintaining transparency is no easy task. Just changing the
tube can effect the sound with just as much effect as changing the tube in V1
of your favorite amp. So complete transparency may be near unachievable.... I
mean perfection would be transparent + the character of the tube you have in
the hole. Understand? 

Prior to the Uncle Spot, the closest stand-alone to having a good top is the
Clark. Clark has a very killer reverb and uses a bit of a circuit tweak to improve
the top on the dry side and it works... pretty much. Not perfect and its
somewhat effected by the Mix Control, but it works and the unit is my second
favorite verb. 

Enter Uncle Spot Amplifiers, (, owned and operated by
Ron Veil. I would really like to thank PRS Forumite Mountainblues for the
referal! Ron (Uncle Spot) builds amps and the only thing I know about Ron is
what I have heard from Mountainblues. So with just a tick of info I ordered a
reverb chassis. In conversation with Ron its easy to tell he knows his stuff and
has a tremendous amount of experience. His 3-knob reverb is designed to be a
faithfull IMPROVEMENT on the original and suitable for Studio console use as
well. I am not sure how it varies from the original, but I would say parts
quality, filtering, and a few tweaks here and there. Whatever he does, it
worked cause this thing sounds great! 

Build Quality and parts is top shelf. Ron has picked transformers and
components for sound quality and reliability. Mallory coupling caps and filter
capacitors, 1 watt carbon comp resistors and plenty of those expensive, blue
5watt resistors doing power supply duty. Nice job Ron! It has a modern
3-prong plug, which may add a ground loop, but of course a 2-prong adapter
will correct that. The reverb tank is a 3-spring, and it looks like it may be a
little different than the standard Fender choice. Its an Accutronics, but the
number is a little different than the norm.... and maybe for good reason, cause
it seems to fit the amp perfectly. 

Sound Quality... First test is the dry signal tone quality. I noticed that the
Uncle Spot doesn't do what Clark did to improve the top, but what ever Uncle
Spot has done it worked even better! The dry tone is the best I've heard. Now
the tube in V1 was hissy so I sub'd in a Tungsram (very clear and even
sounding tube with nice top), all other tubes stock. My top gets through with
just a slight rolloff. When A/Bing the reverb unit against a straight cord you
can ear a little loss in the top, and maybe just a touch snug in the bottom, but
very even through the Mids. Every reverb unit I have ever had imparts its own
signature on the dry tone, and the Uncle Spot has the least character of them
all ..... which is good thing! I mean, I bought the unit to add reverb. And the
Character that the Uncle Spot does impart is as pristine and clean as I've
heard with just a touch of warmth. The Dry signal is very clean and high
quality with plenty of headroom. Very Nice! 

The throughput level of the Uncle Spot is almost unity. In most standalones
there is a noticable loss of volume when used, unless they have a volume
control. But I prefer a fixed output, one that can't be adjusted and as close to
unity as possible. The Uncle Spot is right there and I noticed a very slight
variance to unity. Nice. Its all tube and hi headroom so it takes pedals very
well and of course interfaces very well with Guitar amplifiers... as the original
design intended. 

The Reverb effect is controlled by Dwell (drives the tank), Mix (mixes wet with
dry) and Tone (color of the wet signal). First thing that I usually notice with
most Stand Alones is the on-off switch nature of the Dwell and Mix. Minor
adjustments yield huge results and there is very little fine tuning or finness
available. The Uncle Spot has a wonderful range in both the Mix and Dwell. I
think this is where Uncle Spots tank choice comes to play. You can get a
variety of subtle verbs, or you can get the all out bright surf. By using hi mix,
low tone and low dwell, you can get a juicy tonality and let the reverb unit
color your tone. Or in the same settings by brightening the tone you can get a
very wet and lush verb. By running a low mix and a higher dwell you can get
more of an added effect, with a very prominent dry signal. Great for just
adding a bit. The versatility and variety you'd hope to hear in a reverb head. 

For Spring Reverb afficianado's, the Uncle Spot Stand-alone Spring Reverb is
most certainly worthy of an audition. Its very quiet, its very clean, and it adds
a variety of subtle to lush, long decay verbs to your dry original signal. The
lack of dry signal character, and highly usable and toneful controls is what
puts the Uncle Spot on the top for me. I put the Uncle Spot in my signal chain
and could hardly tell its there....until I turned up the verb anyway. And the
verb on this baby is fun to turn up, great tones and variety. A great sounding
Stand Alone Reverb and definitely the best I have used.

(for more photos click HERE)
Perry Roper 
Dr Z Amplification 
Internet Relations Specialist 
Dr Z Amplification 
Dr Z Route 66 Sounds!