Manley TAPE HEAD PREAMPLIFIERS - Manual (Page 7)

ALIGNMENTS
Let us assume that the head has been properly mounted and the cables have been installed and the
preamps are solidly mounted.
Let us also assume you have access to an alignment tape or the reel to be played has well recorded tones
with 50Hz, 100Hz, 1KHz, 10Khz and 15Khz or 20Khz.
1)With the power off - Demag and clean the heads and tape path. Verify input, output and power cables
are correctly attached then turn the power on and wait 5 minutes for the preamp to be well warmed up.
The verniers should each be preset to "50" or a level you have determined through daily use.
The POLARITY toggle switch should be set to "0" not “180”. The INPUT toggle switch should be set
to "MANLEY" not “EXT”
The VLF rotary switch should be set to 12:00 or the middle position. Each step clock-wise adds 1 db at
50Hz. The setting that is generally "flattest" for the “EXT” position is fully counter-clockwise.
2)Play the 1Khz and adjust the vernier marked LEVEL for 0 VU on the meter.
Verify correct tape path, height, wrap, etc.
3) Play the 10Khz and adjust the vernier marked HF for 0 VU on the meter.
Verify correct azimuth and that the tape path is stable.
4) Play the 15Khz and adjust the vernier marked VHF for 0 VU on the meter.
Verify correct azimuth here too.
5) Play the 100hz and adjust the vernier marked LF for 0 VU on the meter.
6) Play the 50hz and adjust the switch marked VLF for the best setting.
7) Repeat steps 2 thru 7. If no adjustments are necessary then good - You have aligned and then checked
for any mistakes or drift.
8) If you are going to do a record alignment follow the procedure recommended by the machine
manufacturer. Start with bias, then 1Khz and 10Khz record adjustments. You may re-adjust the LF or
VLF particularly if you started with “Standard” alignment tape due to “fringing” with full track tapes.
9) Play music. You may want a towel to catch the drool.
If you are using the preamp in the “EXT” mode steps 3 thru 5 are not going to do anything. Follow your
usual procedure. Only the VLF and GAIN control will be active. Either use the Manley GAIN or original
REPR GAIN to adjust initial level or both if you intend to compare “sound”. In the EXT mode the
original preamp and EQ are used to drive the Manley Preamp’s vacuum tube output stage. This gives at
least an audiophile quality “Class A” line driver as opposed to a “Class B mini power amp” stage
feeding a questionable transformer, as is found in most machines. The resulting improvement is
substantial but not as complete as having 100% tubes in the chain. Having the option may allow some
tapes to be played - if for example, they are 1/4 track and you have 1/2 track HI-Z heads, or they are 3 1/
2 IPS, or the tape sounds weird enough to get you creatively experimenting with options.
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ALIGNMENTS