The Manley Reference Preamplifier followed on from the Control Master Preamps, and was also available in both Line Onlyand Phono & Line versions. Here is some sales pitch text from the mid-1990's:
What sets this preamplifier apart is the separate vacuum tube regulated power supply (not shown). In the PHONO version, ahead of the MM RIAA circuitry, is found our superb 'Floating Symmetrical Mode' Moving Coil stage, which receives the fragile MC cartridge output as a fully differential signal offering excellent hum cancellation properties and wide spatial retrieval abilities. Gain of this stage is adjustable and is ideal for low impedance and medium to high output MC cartridges. Each of the two channels is on separate gold plated printed circuit boards and suspended on vibration-isolated rubber mounts. The BALANCE TRIM knobs on each channel change the amount of global feedback is applied to the line stage. This affects the slew rate, speed, and sound of the tube stage, besides changing how much it is amplifying. For more information about variable feedback, read Notes on Negative Feedback.
There was a separate outboard power supply in a 1 1/2U tall billet chassis shown in the photo below. A meter indicated your incoming mains voltage coming out of the wall. There were two vacuum tube regulated circuits for the B+ supply, one for left and one for right, and the good ol' 7812 linearly regulated lines for the heaters.
There were six inputs. Left and right input select were separate for ultimate channel-to-channel separation, built on super high quality ceramic switches. The LINE version offered an IC-coupled set of XLR balanced inputs and outputs. The volume control was a discrete resistor stepped switch jobbie for perfect L-R tracking.
The 24K GOLD faceplate version is pictured above. There were also some of these built with the "Manley Blue" faceplate color as shown below. See FAQ 124K related to this faceplate color thing.
These PHONO and LINE Manley Reference Preamplifier models were built at The Manley Labs factory from 1994 until 1999.
There was a previous version of "Manley Reference Preamplifier" which was built at the VTL factory from 1988 until 1993. It had a different power supply and different layout entirely, and it said "VTL" and "Vacuum Tube Logic" on the power supply and main unit. See below further down the page for more info.
In 2009 we re-issued the Manley Reference LINE Preamplifier for a limited production run exclusively for Korea. The original gold plated printed circuit boards were used for the 2009 production run.
The 2009 power supplies were improved with quieter transformers and better power connector and moved into our larger chassis.
- FSM stage: 2 x 6072A tubes
- MM stage: 2 x 12AX7 tubes
- Phono Output: 2 x 12AT7 tubes
- LINE Stage: 2 x 12AU7 tubes
- Buffered Record: uses 2 x 12AT7 tubes
- Main Output: 2 x 6414 tubes
- Separate Regulated PSU: 2 x 6GF7A, 2 x OA2
- All-Triode design
- Precision stepped Volume control
- Variable Feedback dual controls for balance function and sonic variation
- MUTE switch
- Buffered Record Output
- 24K Gold plated faceplate on some units, "Manley Blue" anoddise on others
- Power consumption Normal Operation: 106 watts
- Power Consumption during Soft-Start/Ever=Warm: 39 watts
- Balanced & Unbalanced outputs
- Power Supply Unit Factory set for 100V, 120V or 220-240VAC operation for original destination country's mains voltage.
- Operating Mains Voltage changeable with power transformer re-wiring, meterscale circuit modification, and fuse values changes.
- Mains Voltage Frequency:
- Mains Fuses: 1/2 Amp @ 120v; 1/4A @ 230v SLO-BLO 1 1/4" x 1/4" MDL or MDA 3AG
- Dimensions, Preamp: W=19", L= 12", H=5 1/4"
- Dimensions, Power Supply Unit: W=19", L=9 1/2". H=3 1/2" on Tiptoes
- Shipping weight: 17 Ibs. (Preamp) + 18 Ibs. (PSU) in a 22" x 22" x 16" BOX weighing 40 lbs.
Older Manley Reference Preamplifier (built at the VTL factory) 1988 - 1993
if you have one that looks like this, then it's an older VTL-built one, before Manley Labs existed.
The volume control situation was a stepped ElectroSwitch switch built with 1/4watt resistors for the big steps "COARSE" and then a blue Bourns dual pot for the "FINE" adjust. And since the blue Bourns pot didn't track left to right, in addition to the big switch there was a BALANCE control so you could get back to where you were supposed to be.
That's the rear view. See the VTL serial number sticker? Yes, that's another indication that it was built at the VTL factory before Manley Labs was formed.
A customer sent this in thinking his unit had been all modified by someone, but no, they were built this way - that's a bone-stock unit there.
Tube callout for this older version VTL-built unit is:
Rear board FSM MC stage: 2 x 12AX7 or 6072 if you want. Left and right.
Front boards, working inside out, per each board:
2 x 12AX7 for the MM/RIAA stage plus cathode follower output buffer for that stage.
1 x 12AU7 for the LINE gain cascade stage
1 x 12AT7 for the LINE and RECORD output cathode followers next to the two big WIMA caps.
The only Owner's Manual for these VTL-built ones was whatever was written up in The VTL Book. I do not have any specs on the older ones. I haven't seen one in a long time, sorry.