Errata – Manley The WAVE DAC/Preamp 24/96 Version Serial Code WAVE016-present 2002 - present User Manual

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The WAVE's DAC uses Burr-Brown PCM1704 D-A converters operating at 96 KHz at all times. All inputs below
96 KHz are upsampled to 96 KHz before conversion. The upsampled output is clocked out via a Low Phase Noise/
Low Jitter precision crystal oscillator to eliminate any interface jitter or timing problems with the incoming datastream.
Multiple power supplies are used, with additional regulation and filtering located near critical components.
Differential Passive LC filtering is used on the voltage output of the DAC PCB. High Speed JFET Current to Voltage
Conversion with differential output is used to drive the Passive LC Filter before the DAC output joins up with the
analog input select buss.

Analog switching is accomplished with gold contact sealed relays. Left and right relays are well separated and single
relays switch both halves of a balanced signal. Virtually all of the logic involved for the front panel buttons and LEDS
is taken care of on the front panel board which uses standard TTL logic (no clock) for all functions. The only oscillator
involved is enabled only while a button is pushed. In STANDBY mode one small power transformer keeps the logic
circuitry alive while the big power transformer (which runs all of the other power supply rails) is disconnected from
the AC mains power. The pushbutton switches are super reliable made by EAO. The Volume Control is a custom-made
4 deck precision conductive plastic motor driven 50K attenuator made by ALPS. Left/right tracking is exceptional.
We use an ultra-low capacitance, well-shielded, balanced silver-core wire provided to us by Synergistic Research for
point-to-point audio connections.

The first stage of the line amp acts to cancel noise and distortion through high common mode rejection. The input to
this line amp is arranged to accept both balanced or unbalanced signals. The output stage is our tried and true fave,
the direct-coupled White Follower. We expect most folks to get five to ten years tube life from the factory supplied
tubes. Sometimes this is optimistic. If replacing one or all tubes do not attempt to use any but the same type tube as
removed. The 7044 or 5687 output tube has an unusual pin-out and most other tubes will not work here without cutting
up the board to swap some pins. We select the 12AX7 input tubes for best fidelity, lowest noise and low microphonics.
Picky selection is critical due to the fact that the volume control is ahead of the tube line amplifiers and it will not
attenuate any tube "issues". Any problems such as excessive hiss or microphonics will be hanging out there all the time.
This is why good tube selection is important. Manley Labs always has good tested tubes in stock if needed. If you need
spare tubes you can order them from us and we will select them for best performance in a WAVE.

OUTPUT 1 receives its signal directly from the plate-cathode White Follower output junction through an expensive
MultiCap made by RelCap. On its way to OUTPUT 3, the signal passes through a custom 1:1 Manley transformer,
the 9811, made right here at the Manley Labs factory. The 9811 has a special tertiary feedback winding that goes back
to the front end of the tube preamp stage. In the professional world where balanced lines are standard, transformers
are acknowledged as the absolute best (and most expensive) technique. Not only does a transformer provide a true
balanced output, but it can also be "floating" which isolates grounds between equipment if needed. However, adding
a transformer will impart something to the sound, however benign that might be.

The external power supply utilizes overkill ripple 'pi' filtering for the B+ voltage supplies with each channel filtered
separately. The tube heaters are DC regulated to 12 volts. The Logic and LED 5V rail is regulated in two stages: first
to 12V in the supply and then to several individual 5V points for the DACs, panel, relays, and LEDs. There are also
plus and minus 15 volt regulators for the DAC (plus the Insert Send and Return balanced to unbalanced converter ICs).
The power supply depends on a return signal from the WAVE audio chassis in order to operate and so thus it should
not be tested in isolation. The multi-pin connector has 4 extra-heavy duty pins for the filament and logic power and
12 heavy duty pins for the remaining power systems. The supply cable is a combination of 16 wires in 14 and 20 guage.
The plastic connector shell rattles less than the alternative metal version.

The WAVE uses a .375" thick anodised billet aluminum panel mounted to a steel chassis. There are removable panels
on the chassis bottom for easy access during servicing and ventilation slots in the front, bottom and top of the chassis
to keep everything cool to extend life of the components, especially the power supply electrolytic capacitors. Heat is
the ultimate enemy for those puppies! All connectors are gold plated including the power supply to provide minimal
oxidation resulting in highest integrity connections and long reliable life.

ERRATA