- Fosi Audio ZA3 Balanced Stereo Amplifier
- Power Adapter
- User Manual
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Fosi Audio ZA3 Balanced Stereo Amplifier
- Compact Class D stereo amplifier for passive speaker systems
- Supports stereo mode and mono mode for scalable audio setups
- RCA, XLR, and 1/4 inch TRS inputs for flexible source connection
- Active subwoofer output supports powered subwoofer integration
- 12V trigger input works with compatible system components
- Texas Instruments TPA3255 amplifier chip
- Supports 2 to 8Ω speaker impedance
- Swappable DIP8 dual op amps for advanced sound tuning
The Fosi Audio ZA3 Balanced Stereo Amplifier gives compact audio systems a flexible power center for passive speakers, powered subwoofer integration, and balanced source connections. Its dual mode design lets the amplifier work as a stereo amplifier for a two-channel setup or as a mono amplifier when paired into a scalable left and right configuration.
Balanced Input Flexibility
ZA3 supports RCA, XLR, and 1/4 inch TRS input options, giving listeners multiple ways to connect DACs, preamps, streamers, and other line-level audio sources. The balanced input path is useful for systems where lower interference and cleaner signal routing matter, especially on desks, shelves, and compact component racks.
Power for Stereo or Mono Systems
With a Texas Instruments TPA3255 Class D amplifier chip, the ZA3 supports 2 to 8Ω speakers and rated output up to 155W x2 at 4Ω with a 48V/5A power supply in stereo mode. In mono mode, it delivers rated output up to 235W x1 at 4Ω, letting users pair two ZA3 amplifiers for a dedicated left and right speaker setup.
Subwoofer Output and System Control
An active subwoofer output makes it easier to build a 2.1 channel listening system with passive speakers and a powered subwoofer. The 12V trigger input allows synchronized power control with compatible devices, reducing the need to turn each component on or off separately.
The aluminum alloy chassis, side ventilation, dust covers, and whole-body heatsink support stable operation in compact spaces. Swappable DIP8 dual op amp support also gives advanced users room to tune the amplifier to their preferred sound profile.
Product
| Brand | Fosi Audio |
| Model | ZA3 |
| Product Type | Balanced Stereo Amplifier |
| Channel | 2.0 |
Amplification
| Amplifier Chip | Texas Instruments TPA3255 |
| Amplifier Type | Class D |
| Rated Output Power with 48V/5A | Stereo 155W x2 at 4Ω, Mono 235W x1 at 4Ω |
| Rated Output Power with 32V/5A | Stereo 95W x2 at 4Ω, Mono 110W x1 at 4Ω |
| Supported Speaker Impedance | 2 to 8Ω |
Audio Performance
| Frequency Response | 20Hz to 20kHz, plus or minus 0.1dB |
| SINAD | 89dB |
| SNR | At least 106dB |
| Dynamic Range | At least 106dB |
| THD | Below 0.006 percent |
Inputs and Outputs
| Input Mode | RCA, XLR, 1/4 inch TRS |
| Output Mode | Speaker Output, Active Subwoofer Output |
| Speaker Connection | Banana Plug or Bare Wire |
| Trigger Input | 12V Trigger |
Power and Build
| DC Input Range | 24 to 48V |
| Power Supply Support | 32V/5A, 48V/5A |
| Device Dimensions | 15.49 x 18.39 x 5.08 cm |
| Weight | 1.78 kg |
| Chassis | Aluminum Alloy |
Starting at $12.49/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 $37.50
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.
