MT502 - Amplifier Bellari - Free user manual and instructions

Product Type	Stereo Tube Amplifier
Brand	Bellari
Model	MT502
Chassis	Black steel, rack-mount compatible
Tube Complement	2 x 12AX7 (preamp)
Inputs	2 x RCA (Line), 1 x XLR (Mic)
Outputs	1 x RCA (Line out), 1 x 1/4" Headphone
Frequency Response	20 Hz - 20 kHz ±0.5 dB
Signal-to-Noise Ratio	>90 dB (A-weighted)
Gain	40 dB (Line), 60 dB (Mic)
Power Requirements	120V/60Hz or 230V/50Hz (selectable), 30W
Dimensions (W x D x H)	19 x 8 x 2.5 inches (483 x 203 x 64 mm)
Weight	6.5 lbs (2.95 kg)
Operating Temperature	32°F to 104°F (0°C to 40°C)
Features	Volume control, Bass/Treble EQ, Phantom power (+48V)
Ventilation	Allow 4 inches clearance above and behind for airflow
Tube Replacement	Remove top cover, gently pull old tubes, insert new ones (consult manual)
Safety	Do not expose to moisture. Unplug before servicing. Use grounded outlet.
Certifications	CE, FCC, RoHS
Accessories Included	Power cord, rack mount ears, user manual

Frequently Asked Questions - MT502 Bellari

How do I connect speakers to the Bellari MT502?

Use the RCA Line Out jacks to connect to an external power amplifier, which then drives your speakers. The MT502 is a preamplifier and does not have speaker outputs.

What tubes are used in the MT502 and how often should they be replaced?

The MT502 uses two 12AX7 tubes in the preamp section. Typical tube life is 2000-5000 hours depending on usage. Replace them when you notice degraded sound quality or excessive noise.

How do I replace the tubes?

1. Turn off and unplug the unit. 2. Remove the top cover screws. 3. Gently rock the old tubes back and forth while pulling upward. 4. Insert new tubes aligning the pins with the socket. 5. Replace cover and power on. Avoid touching tube glass with bare hands; use a cloth.

Why is there a humming or buzzing sound from my MT502?

Hum can be caused by poor grounding, proximity to power transformers, or a bad tube. First, try relocating the unit away from other electronics. Ensure cables are shielded and connections are tight. If hum persists, try replacing the tubes one at a time.

How should I clean the MT502?

Use a soft, dry microfiber cloth to wipe the exterior. Do not use any liquid cleaners or aerosols. For the front panel, a slightly damp cloth (water only) can be used, but avoid getting moisture near vents.

What is the warranty on the Bellari MT502?

Bellari offers a 2-year limited warranty from the date of purchase covering defects in materials and workmanship. Retain your receipt for warranty claims.

Can I use headphones directly with the MT502?

Yes, the MT502 features a 1/4 inch headphone output on the front panel. Plug in headphones with an impedance of 32-600 ohms for best performance.

What are the power requirements for the MT502?

The unit can be configured for 120V/60Hz or 230V/50Hz via a voltage selector switch on the rear panel. It consumes approximately 30 watts. Use the supplied power cord.

Is the Bellari MT502 rack-mountable?

Yes, the MT502 comes with rack mount ears and fits a standard 19-inch rack. It occupies 2U of rack space. Ensure adequate ventilation when rack-mounted.

What is the gain of the microphone input?

The microphone input (XLR) provides approximately 60 dB of gain, suitable for dynamic and condenser microphones. Phantom power (+48V) can be enabled via a rear switch.

USER MANUAL MT502 Bellari

I/ O Connectors: RCA

Input Impedance: 30-300 ohms

Output Impedance: 30k ohms

THD: .02% @ 1KHz

Size: 4"w x 1.1"h x 4"d

Weight: 2 lb

DO NOT OPEN THE MT502. NO USER SERVICEABLE PARTS ARE INSIDE. ALL WARRANTIES ARE VOID IF ANY INTERNAL COMPONENTS ARE DAMAGED DUE TO USER ERROR.

CE

Salt Lake City, UT 01/19

MT502 μ

QUICK START GUIDE

Thank you for purchasing the MT502. We spent a considerable amount of time designing and developing the MT502. Hundreds of hours listening and improving the design. We hope you enjoy using the MT502, and that it makes listening to your music collection rewarding. We sincerely appreciate the opportunity to build a product for you and participate in your love of quality music and sound. We love what we do and we're happy to help. All Bellari products are hand built in Salt Lake City, Utah by people who care about high quality music.

The MT502 is a moving coil to moving magnet transformer. It converts low impedance output moving coil cartridges to a higher impedance output for use with moving magnet pre-amps.

The symbol stands for MU as that is the metal now encasing the MT502 MK2 transformers. MU Metal is one of the best shielding materials known. All step up transformers are of a similar design. They have two transformers inside to step up the low level signal from a moving coil cart. The transformers are very expensive to manufacture, that is the reason for the high prices of such items. Our transformers are hand wound, potted, encased in an all MU Metal chassis and then placed into a copper chassis that has been gold plated. This is all done one at a time, by hand.

What's in the box?

1 - Made in USA MT502
1 - This owners manual
1 - Love for great audio

CONNECTION:

INPUT: RCA's for connection to your turntable with moving coil cartridge.

OUTPUT: RCA's for connection to a phono preamp with RIAA equalization.

LIFT/GROUND SWITCH: This switch connects or disconnects the ground connection between the INPUT and OUTPUT RCA's. This might be useful for reducing ground loops. SET THE SWITCH IN THE POSITION THAT SOUNDS BEST.

TURNS RATIO SWITCH: This switch will allow you to select between a low output moving coil cart and a very low output moving coil cart. The 12:1 is designed to work with carts like the Denon DL103 or 103R or similar. The 30:1 is designed to work with carts that need more gain/level. The turns ratio switch can be set to wherever you feel it sounds best. If you have a higher output cart be careful not to confuse a level increase from the 30:1 setting with proper frequency response. The 30:1 will make your cart louder. The MT502 or any cart you connect to it will not ever be damaged by setting the ratio switch in either location.

GROUND POST: For connection of your turntables ground wire. In some cases the turntable ground wire might have better results if connected directly to you phono preamp bypassing the ground of the MT502. Try both ways and see what sounds better.