Owner`s manual

Almost all phonograph cartridges are balanced sources. Thus the MP-1 allows you to set up your turntable as a fully-balanced source, with considerable
sonic advantage. For best results, follow the connection scheme outlined below:
1) Use a cable that has two signal conductors PLUS a shield for each channel. The two conductors are for the plus and minus outputs of the cartridge, and
the shield connection becomes the tone arm/turntable ground connection and is common to BOTH channels.
2) Pin number one of any XLR connection should always be ground as per industry standard.
3) Pin two of the XLR phono input corresponds to the "+" or non-inverting output of the cartridge, and pin three is the "-" or inverting output of the cartridge.
Absolute system phase can be corrected from the front panel.
4) There is no need for an independent ground wire from the arm to the preamp.
If you set up the cable correctly, there will be NO hum whatsoever, even if the cartridge output is too low for the preamp. Many tone arms use a five pin
connector that plugs into the bottom of the arm. If this is the case in your system, you may order a tone arm cable with the right connections from almost any
cable manufacturer. If your arm has RCA connectors at the output, an adaptor cable can be made that will work. The shield connection of the RCA must
become the connection to pin 3 of the XLR connector, and the tone arm ground connection should be made as described above. ON NO ACCOUNT should
you allow the shield connection of the RCA to become the shield for the cable, as this will result in a loud hum.
The cartridge loading is achieved by installing resistors on the loading terminal on the rear panel. A screwdriver is all that is needed for attachment. You will
have to experiment to obtain the correct value. One hundred ohms is common with many low output cartidges since the early 1990's.
RF problems may be encountered if the tone arm tube is not grounded. RF beads installed in the interconnect cable can sometimes alleviate this problem.
The trick is to eliminate the RF before it gets into the preamplifier, so treat the ground connection with RF beads also. For best results, the phono cable
should be shielded.
High-Level Hookup
The auxiliary inputs are high impedance. Thus you may use any input as a source for the MP-1. If you are using a low impedance source, a low impedance
termination is recommended for better sound. A single-ended source can also be used, by applying the signal between either pin two or pin three of the input
XLR, and ground. The unused input (pin three or pin two, respectively), may have to be shorted out to prevent noise. Pin two of all the XLR inputs is the
noninverting input, per industry standard.
The tape outputs are high impedance. Use a high-quality cable for best results, and keep the cable as short as possible. The minimum drive impedance is
10K-ohms.
The tape monitors are a single-ended, non-inverting, high impedance input.
NOTE: the INVERT switch will not function in one position if a single-ended input is used (and does not work in the 'invert' position with the tape monitors).
NOTE: Use of NOS tubes may result in inferior performance. There are many counterfeit tubes on teh market, and many that are advertised as NOS tubes
when in reality they are used. Only buy from a reputable vendor, with proper assurance that the tubes can be returned if they are unsatisfactory! We advise
that you do not go overboard with NOS tube types, as the prices paid for the results can be high compared to other changes you can make, fleeting or both.
Of course there are exceptions, but especially in the case of the phono tubes, the investment is often not worthwhile.