Manley Enhanced Pultec Mid Frequency Equalizer, Руководство пользователя

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IT MAKES NOISES WHEN THE FRONT PANEL IS TAPPED - An easy one. Some tubes become microphonic over
time. That means they start acting like a bad microphone. Vibration has caused the supports for the little parts in the tube to
loosen and now the tube is sensitive to vibration. Easy - Replace the tube. Which one? The one that makes the most noise
when you tap it (usually the 5814). It will have to be on , connected and speakers up but not too loud (save the speakers).
IT GOT HISSY - Also easy. This is again a common tube symptom. You could swap tubes to find the culprit but an educated
guess is OK too. Generally the first tube in the path is the one with the most gain and dealing with the softest signals. The
usual suspect is the tube that is usually located closest to the front panel volume pot or the 5814. You may find that you need
to choose the quietest tube out of several of that type. We do this at the factory.
DISTORTION - This might be a tube. Swapping is a good way to find out. It may be a wiring thing or mismatch as well.
Wiring problems usually accompany the distortion with a major loss of signal. Mismatches are a bit tougher. Without even
explaining the term "impedance" it is enough to say that a lot of gear is simply not capable of driving pro levels and low
impedances. It will sound like lost headroom, early clipping, distortion on peaks. Often changing the order of processors will
do the trick. Another not so rare place to look is the patchbay, your settings, the meter levels - it happens. This unit has high
input impedances, low ouput impedances and more headroom than most gear but will lose some of that headroom into 600
ohm inputs found in vintage gear. You can usually remove that 600 ohm (termination) and be better off.
DC OR SOMETHING AT THE OUTPUT THAT IS INAUDIBLE - This might happen and it might be accompanied with
a strange hum or little whistles as it warms up. It only seems to occur with long cables. It happens on an older unit but not
on the newer one. Years ago we found a problem with our line driver section when it fed very long or cheap wire. The output
would tend to oscillate in the inaudible ultrasonic frequencies ( 200 kHz to 500 kHz) into high capacitance like a long cable.
We cured it by adding a simple 47 to 100 ohm resistor at the XLR. Newer units should not have a problem but if you have
an old one, we can FAX you a 25¢ fix. Real DC at the output would be such a rare find that we would be pretty surprised.
We use a $30 output cap to block DC. Most manufactures use a 30¢ electrolytic cap but we don't like the sound or reliability
of these. We also had some low level, low frequency output caused by AC mains fluxuations. We cured that with a unique
high voltage shunt regulator. Older units may can get this fitted if needed.
THE KNOBS "FEEL" LOOSE - This is a complaint that we get. We use Bourns conductive plastic pots. They are the best
sounding, most reliable pot that we know of. David showed us that they have less coloration than Penny & Giles faders on
big consoles. Unfortunately they "feel" loose. We could use cheap unsealed pots like most other companies but then we would
not "feel" so good about putting the Manley name on the panel. The only better solution we can offer is the detented Grayhill
11 position gold contact rotary switches that we use for the mastering versions. This will cost you. You may notice that we
are proud to share the name of the makers of the parts we use. A lot of research and listening goes into our choices. The name
on the front panel is also the name on the desk of the parts buyer.
WHAT CAN BE DONE TO MAKE A TUBE PROCESSOR LESS FRAGILE - There is a strange and false rumor about
tube gear being unreliable and fragile. They seem to forget about all those original Pultecs and LA-2As still in daily operation
after 30 or 40 years. Many of them have been abused beyond belief. At least 95% of the ones made are in full daily operation.
What about all those old tube guitar amplifiers still working hard after the all the miles in the back of a truck. Tube mics,
like all condensor mics, are a bit fragile but it has usually been the mic capsule or cables and not the tubes. Now how much
solid state gear from the 70's and 80's still works (or is worth using)? It would seem that 40 year old tube gear is more reliable
than 20 year old solid state and more useful. On the other hand, we expect much of the the new cheap gear to have a short
life whether it uses tubes or solid state. "Fragility" is a question of "build quality" far more than the technology used.
The only tried and true way to increase the reliabilty factor in tube or solid state gear is to buy the well made stuff and then
carry back-up units like every touring company. If you can't have a "spare" unit at least have a few spare tubes. Do
manufacturers of solid state say "carry a few transistors or IC's or do they say "send the unit back with an approved RMA"?
We respect and use the some of the "old" techniques of manufacturing - using solid, thick metal chassis, hand
soldering, fewest possible connectors and "over-engineered" designs. We also get to use better parts than were available back
then. We can use conductive plastic sealed pots, gold contact jacks and switches, high temperature capacitors and more stable
1% tolerance parts. We can also use solid state where it is best used - in the power supply. Silicon diodes have some advantages
in some of our designs and we often use HexFets for regulators, with zeners.
We do all we can to make this unit not only reliable but also a unit you will enjoy for decades. We rarely get gear
back for repair and very, very rarely charge for anything except tubes. We used to give a "lifetime" free repair guarantee
(except tubes) which was expained as your lifetime and/or the person you may have sold the gear to. Pretty gutsy but it shows
how we feel the gear is gonna last. We officially modified our policy when more gear was becoming rentals and used live,
and almost industrially however we do believe in supporting our customers to every practical extent.
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