Manley Labs STEREO EQ - Manual (Page 28)

GETTING DISTORTION WHEN WE BOOST A LOT. No doubt. The Mini Massive by itself should have enough
headroom so that mega-boosts won't cause clipping in it, however, it can push out about +30dBv, 6 or 8 dB more than most
gear can accept without clipping. You're gonna have to turn something down, whether it is the signal feeding the EQ, the "Gain
Trims" on the EQ's front panel or the input levels of the next piece. That last option may not help if there is any op-amps before
its own volume control and unfortunately that is pretty common.
THE GAIN SEEMS OUT OF CALIBRATION - Wait a bit and see if it just needs to warm up. There are only two trimmers
inside and they are for adjusting the gain of the two channels up or down a few dB. More than that and you either have a bad
cable or the back panel I/O switch needs to be in another position.
Once in a while we get a call from a client with a "digital studio" with confusion about levels. They usually start out by using
the digital oscillator from their workstation and finding pegged VU meters the first place they look and they know it can't be
the workstation. Even a -6 level from their system pegs the meters. Some of you know already what 's going on. That -6 level
is referenced to "digital full scale" and the computer might have 18 or 18.5 or 20 dB of headroom built in. That -6 level on
the oscillator is actually a real world analog +12 or +14 and those VU meters don't really go much further than +3. There are
a few standards and plenty of exceptions. One standard is that normal (non-broadcast) VU meters are calibrated for 0VU =
+4 dBm =1.228 volts into 600 ohms (broadcast is sometimes +8dBm). Another standard is that CDs have a zero analog
reference that is -14 dB from digital full scale or maximum. This allows sufficient peak headroom for mixed material but would
be a bad standard for individual tracks because they would likely distort frequently. This is why digital workstations use higher
references like 18 and 20 - to allow for peaks on individual sounds. It may be too much in some cases and too little in others.
Add two other sources of confusion. Peak meters and VU meters will almost never agree - they are not supposed to. A peak
meter is intended to show the maximum level that can be recorded to a given medium. VU meters were designed to show how
loud we will likely hear a sound and help set record levels to analog tape. By help, we mean that they can be only used as a
guide combined with experience. They are kinda slow. Bright percussion may want to be recorded at - 10 on a VU for analog
tape to be clean but a digital recording using a good peak meter should make the meter read as high as possible without an
"over". Here is the second confusion: There aren't many good peak meters. Almost all DATs have strange peak meters that
do not agree with another company's DAT. One cannot trust them to truly indicate peaks or overs. Outboard digital peak meters
(with switchable peak hold) that indicate overs as 3 or 4 consecutive samples at either Full Scale Digital (FSD) are the best.
They won't agree with VU meters or Average meters or BBC Peak Programme (PPM) meters either. Each is a different animal
for different uses. When in doubt, use the recorder's meters when recording - they "should" be set up and proper for that
medium. Also important - if your DAC has gain trims, and these trims are "out" it can cause distortion, confusion, and a variety
of mis-matches. If you don't have calibration tapes or sources - get them, and if you do have them - learn how to use them, and
definately use them. Don't guess, especially if you suspect a significant problem. This is not the type of thing "phone support"
is usually good at finding. We have seen guys spend thousands on new gear only to find out a little screwdriver trim would
have solved their problems.
We also expect to get calls from people who can't hear any difference when they change the "Transformer Switch" or the
"Input Output Level Switch" on the back panel. Unlike plug-ins, real analog equipment may have switches that do very subtle
things, especially if those switches happen to be on the back panel. Of course, many people these days expect switching in
a transformer "SHOULD" be a major effect, because after all, several companies offer 4 products that are really one product
with 4 different transformers available. Maybe 3 of those transformers are questionable, maybe all 4. A good transformer
properly used should be near inaudible and maybe just and expensive and weighty component to accomplish a particular
function. Contrary to a lot of marketing hype, it really isn't all that challenging to design or purchase a flawed transformer
or mis-use it. The "big secret" for vintage warmth is low permeability laminations (like steel or other commonly available
materials) which forces bigger transformers. The downside is that the more obvious and identifyible a sonic color becomes
the more it becomes a one trick pony, and less universally useful. We should keep in mind that designers of vintage gear were
not aiming for funky colors to warm up digital - they were trying to build good sounding gear that did minimal damage. So
the back panel switches are in the tradition of vintage pro gear, meant to be subtle and not obvious in-your-face audio-damage.
OK, so if your Mini Massive is not heating up your cold digital tracks while bands are bypassed, not sounding like a vintage
warmth generator or some functions seem more subtle than you expected, it is not broken. On the other hand, if you can't find
any setting that doesn't make the sound you are working on at least a bit better, then it may be broken. In fact, the usual problem
is not finding one setting but finding several good possibilities and needing to choose just one. If you are having that problem,
the Mini Massive is probably not broken.
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