Professional 4 channel Riaa pick-up / Phone preamplifier
With the PMT 901 you connect not one but two turntables!
Most broadcast studios use not one but two turntables. That’s why we built not two, but four high-end Riaa amplifiers in one housing. It not only saves space in the studio, but also significantly reduces costs.
The PMT 901 is used as an interface between turntables and professional studio equipment. The PMT 901 provides solid amplification of the volume level & adjustment of the impedances so that it can be connected to a mixing console without any problems. The RIAA correction filter ensures that the frequency curves of the records are adjusted.
There are four cinch / tulip inputs and four specially designed high end balanced XLR outputs. The gain can be easily adjusted via the rear trimpots if needed.
Built like a tank, no compromise on quality
Making it the same quality as they did 35 years ago, and if possible even better. That was the aim, and it succeeded.
It became a well thought-out project, the best phono preamplifier with a super sound!
HOUSING
Complete metal housing (powder-coated top, bottom and sides) prevents interference (e.g. transmitter radiation) from the outside.
EXTERNAL POWER SUPPLY
Maximum protection against stray magnetic fields, which is why an external wound transformer was chosen. (So no much cheaper switched power supply)
(So no much cheaper switched power supply)
DOUBLE STABILIZED
A doubly stabilized internal rectifier that is also triple decoupled against high frequency signals.
This makes hum and radiation a thing of the past.
CONNECTORS
Gold plated input connectors and Gold plated rock solid Neutrik XLR for the output.
There is even a connector to connect the record player’s ground connection.
ADJUSTABLE INPUTS
Not every element has the same output. If necessary, the gain can be easily adjusted per channel at the rear.
100% DURABILITY
Thanks to the through-hole technology* and the Long life Rubycon capacitors, 24/7 use is no problem at all.
(* no small smd that damage faster).
RACK MOUNT
Thanks to the mounting eyes, the PMT 901 can easily be mounted in a 19 inch rack (1U).
RIAA correction
RIAA stands for Recording Industry Association of America. It is actually an adjustment of a technical problem that was encountered during the pressing the records.
Low tones need deep grooves, while high tones need thin grooves. To prevent the deep grooves from adversely affecting the thin grooves, a tone correction has been devised that is incorporated into the recording. Shortly, they weakened the low tones and amplified the high tones.
This correction must of course be canceled later because otherwise it would not sound. And that’s what we do in this preamp.
Balanced outputs
In professional (radio) studios, balanced inputs / outputs are always used. A big advantage is that it prevents hum and interference that can be incurred in the cables en route. This is a big plus, especially with longer cables.
The output voltage is also higher, namely 1.55v instead of 0.775 in consumer electronics.
That is why great care has been taken with the four output amplifiers, they are all calibrated and sealed in our technical department to guarantee 100% quality.
In addition, we have designed the output stage in such a way that if the signal is made unbalanced, the voltage automatically reaches consumer level. This means that the level of the preamplifier does not need to be adjusted.
Solid, good decoupling, repairable
Usually the point where major cuts are made is the power supply & decoupling. Understandable because this is the most expensive part, but it makes and breaks your project. You don’t want a power supply that hums, oscillates and is sensitive to radiation from the transmitter.
No expense has been spared here either! An external wound transformer has been chosen that has a rock-solid screw-bar connection.
Very expensive compared to today’s switching power supplies, but it is rock solid, does not oscillate and because it is not in the housing of the preamplifier, we are not bothered by magnetic stray fields. Thanks to the double stabilized and triple decoupling, it ensures a stable hum-free voltage.
Europe talks about “right to repair”, we are also at the forefront of that. Complete with easy-to-repair through-hole technology and Long life Rubycon capacitors that are virtually indestructible.
Housing
The gain required to connect a record player to a mixing console or amplifier is so high that it is important to keep interference outside the housing. The slightest irradiation is enough to be clearly audible (hum, etc.).
That is why no expense has been spared on the housing.
The frame has been chosen for solid powder-coated aluminum sides. The top and bottom are made of powder-coated sheet steel.
The front and back are made of dibond and provided with the correct recesses by means of a CNC. This is attached to the sides with 4 pieces of M4 screws.
Specifications
- 4 Neutrik XLR balanced outputs (male) 600 ohms
- 4 RCA/RCA inputs (female)
- 19 inch size + mounting ears
- Robust metal housing
- Ground connector
- Output unbalanced: 75 – 433mv at 5mv input
- Output balanced: 150 – 866mv at 5mv input
- Max output unbalanced: 12 volts
- Max output balanced: 24 volts