Audio Database

PM-55
Commentary

A peak meter unit developed for more accurate use of audio equipment.

An acceleration circuit is installed together with a linear detector and a logarithmic compressor to drive a high-speed meter. It detects the instantaneous peak of the signal, gives instructions, and responds quickly.
Response speed is 100 μ sec and accurate indication is possible without missing even if one wave of 10 kHz input signal comes in.

It is possible to switch the range of 5 levels by matching the voltage level and power level.
Three voltage levels of -20dB, 0 db and + 20 db can be used to check the output of cartridges, pre-out terminals and recording terminals.
In addition, the power level can be adjusted in two steps of 1 x and 10 x, and the output that appears at the speaker terminal of the power amplifier can be read.

Wide scale type of -50dB to + 5 db is used for the meter.
It can be read in a wide range of voltage from 300 mv (-20dB) to 17.7 v (+ 20 db) and power from 300 mw to 300W.

Two input lines for voltage level and one input line for power level are provided.
The input for voltage level is a US pin to connect a pre-out or RECOUT.
Since the two systems are connected in parallel, even when a preamp with only one pre-out is connected, the signal path will not be blocked by connecting the power amplifier to the terminal of the other system.

By mounting the separately sold Carrying Handle TO-1 (¥ 3,000), 480 mm width standard rack mounting is possible.

Model Rating
Type Peak meter unit
Input Sensitivity / Impedance LEVEL Input : 10 v, 1 v, 0.1V/50k Ω
POWER Input : 10W, 100W (4, 6, 8 Ω) / 10k Ω
Sensitivity switching LEVEL : + 20, 0, -20dB
POWER : x1, x10
Meter range -50dB to + 5 dB
Rise time 100 μ sec
Recovery time 750 msec (0 → -20dB)
Frequency characteristic 40 Hz ~ 50 kHz + 1.5 dB
Instruction system 0 dB ± 1.5 dB
Pwer 100 VAC, 50Hz/60Hz
Power consumption 4W
External dimensions Width 450x Height 93x Depth 375 mm
Weight 7.5kg
Sold Separately Carrying Handle TO-1 (¥ 3,000)