- MC331 Power Amplifier
- 24V 4.5A Power Adapter
- Remote Control
- User Manual
Trusted & Verified
Fosi Audio MC331 Tube Integrated Amplifier with DAC
- Combines DAC, amplifier, preamplifier, and headphone amplifier functions
- Supports Bluetooth, RCA, USB, optical, and coaxial input sources
- Drives passive speakers with up to 105W x 2 at 4 Ohm
- Includes 3.5mm headphone output for private listening
- Pre-out supports expansion with compatible powered audio gear
- JAN 5654W vacuum tubes add classic visual character
- Mini VU meter displays signal movement for a retro audio look
- Bass and treble controls help tune playback for room or speakers
- Remote control supports convenient listening position adjustments
The Fosi Audio MC331 brings multiple audio components into one compact desktop amplifier for listeners who want simple switching, speaker power, headphone output, and tube character without building a stack of separate gear. It combines a DAC, amplifier, preamplifier, and headphone amplifier in one chassis, making it a practical centerpiece for a computer desk, bookshelf speaker system, TV audio setup, or compact listening room.
Flexible Source Connections
The MC331 supports Bluetooth, RCA, USB, optical, and coaxial inputs, so it can connect with common digital and analog sources. Use Bluetooth for wireless playback from a phone or tablet, USB for a computer, optical or coaxial for compatible digital sources, or RCA for analog components such as a turntable with a built-in phono preamp. Input switching helps the amplifier serve as a convenient hub instead of forcing users to reconnect cables between listening sessions.
Speaker, Headphone, and Preamp Output
For passive bookshelf speakers, the MC331 provides speaker terminal output with a maximum power rating of 105W x 2 at 4 Ohm. A 3.5mm headphone output supports private listening, while the pre out gives users a way to expand into a 2.1-style setup with compatible powered equipment. This makes the amplifier useful for both nearfield desktop listening and compact room audio systems.
Tube Style with Everyday Control
The visible JAN 5654W vacuum tubes and mini VU meter give the MC331 a retro audio look while keeping the controls simple. Bass and treble adjustment let users shape the sound for their room, speakers, or headphones, and the included remote control allows adjustments from the listening position. The all-metal CNC integrated case helps the amplifier feel purpose-built for display on a desk, shelf, or media console.
Product Type
| Type | Tube-integrated Bluetooth amplifier with DAC |
| Model | MC331 |
| Brand | Fosi Audio |
Amplifier Performance
| Maximum Power Output | 105W x 2 at 4 Ohm |
| THD | 0.03 percent or lower |
| SNR | 100dB or higher |
| Speaker Impedance | 4 to 8 Ohm |
Inputs
| Input Modes | Bluetooth, RCA, USB, coaxial, optical |
Outputs
| Output Modes | Passive speaker output, pre-out, 3.5mm headphone output |
Tubes
| Included Tube Type | JAN 5654W vacuum tubes |
| Compatible Tube Types | 5654W, 6AK5, 6AK5W, 6Zh1P, 6J1, 6J1P, WE 403A, 403B, EF95, and other 7 pin tubes |
Controls
| Control Features | Bass adjustment, treble adjustment, volume control, remote control |
| Display Feature | Mini VU meter |
Power
| Power Supply | 24V 4.5A |
Dimensions
| Device Dimensions | 10 x 2 x 2.7 inches |
Starting at $10.83/mo
Estimated over 12 months with Affirm, subject to eligibility and approval.
Flexible payment options available
Interest-free installments and monthly financing may be available through Shop Pay on eligible purchases.
Starting at $32.50
No interest if paid in full by the promotional terms. Minimum monthly payments required and subject to credit approval.
Shipping Policy
Orders of $25 or more qualify for free standard shipping on eligible items.
Most in-stock orders placed before 1 PM EST Monday–Thursday ship the same business day. View Shipping Policy
Free Local Pickup
Please call for store stock availability. Requests made before 2:30 PM EST can be available for next-day pickup. Learn more
Tab: Frequently Asked Questions
How do I return an item?
How do I return an item?
Returns are incredibly simple. Please log into your account, find your item you wish to return and follow the prompts to make a return. If you do not have an account, click here to find your order and make a return.
Will I receive a full refund when I return an item?
Will I receive a full refund when I return an item?
You will receive a full refund when you return an item in its original manufacturer’s packaging, undamaged and unmarked. If the item you are returning is priced at less than $35, you will be charged a 15% restocking fee. Please note you will not be refunded any shipping charges.
How many days do I have to make a return?
How many days do I have to make a return?
You have 30 days to make a return. During the holiday season, from November 1 to December 31, we extend the return window to 60 days.
My item was damaged in transit. How do I place a return?
My item was damaged in transit. How do I place a return?
If your order has been noticeably damaged in transit, we strongly recommend that you refuse delivery and notify us immediately. Claims for missing items or items damaged in transit must be made within 48 hours of delivery. If there is carrier damage, please contact support@focuscamera.com with your order number and a description of the damage.
There’s an issue with my order, what should I do?
There’s an issue with my order, what should I do?
Oh no! Please contact our customer service team so we can resolve the issue immediately. You can call us on 1.800.221.0828, email us at support@focuscamera.com, or send us a message here.
Can I exchange an item?
Can I exchange an item?
We do not currently offer exchanges. Please return the item you purchased within 30 days and order what you’d like instead.
If I ordered a kit, do I have to return all the items?
If I ordered a kit, do I have to return all the items?
If you ordered a kit, you must return all components and accessories to receive a full refund.
I ordered a product that included a free item. I’d like to return it, do I need to return the free item as well?
I ordered a product that included a free item. I’d like to return it, do I need to return the free item as well?
If you ordered a product that included a free item, you must include the free item with your return. If not, your return will not be accepted and you will not receive a full refund.
Do you offer repairs?
Do you offer repairs?
We currently only offer camera repairs at our Brooklyn store. The item must be dropped off and collected in person as we do not accept shipped items for repair. For more information, please call our Brooklyn store on 1.718.431.7900.
What is your return policy?
What is your return policy?
Most items can be returned within 30 days for a full refund. Click here to read our full return policy.
