Description
The ST-MX3 is a compact 3-channel line-level mixer module designed to combine and control multiple line sources into a single line output. It provides three individually adjustable input gains and a line-level output capable of driving balanced or unbalanced loads. The module operates from ground-referenced or floating 24 Vdc and is part of RDL’s STICK-ON series for discreet placement.
Each input includes independent gain control allowing precise level matching between sources. The unit provides isolation between inputs to prevent cross-talk and accommodates signals of different level and impedance. Built for low-noise and low-distortion operation, it preserves audio integrity across a wide dynamic range.
Performance specifications include a 30 kO input impedance per channel, input gain range of -14 dB to +24 dB, and nominal output level of +4 dBu (adjustable). Measured THD+N is below 0.03% across 10 Hz to 20 kHz and frequency response is 10 Hz to 20 kHz within ± 0.5 dB. The mixer offers 18 dB of headroom and noise under -80 dB when inputs are set at 10 dB gain referenced to +4 dBu.
Connectivity is flexible: three bridging inputs accept balanced or unbalanced signals and the output is 400 O to drive low or high impedance balanced or unbalanced lines. The output’s unbalanced level is 6 dB below balanced line level, enabling easy integration into varied system topologies. Power uses RDL SupplyFlex compatible input allowing ground-referenced or floating 24 Vdc operation at 55 mA.
The ST-MX3 is ideal for adding additional line-level inputs to existing mixers or combining sources where level or impedance differs. Typical installations include small control rooms, paging interfaces, distributed audio nodes, and portable recording or playback setups. The small footprint and Stick-On form factor permit mounting in confined spaces or behind equipment panels.
Installation is straightforward with minimal configuration required and stable mechanical construction for long-term use. The compact package dimensions minimize rack or enclosure space requirements and the low current draw simplifies power distribution. The design emphasizes reliable audio performance and easy system integration for installers and audio technicians.
Free Ground Shipping
We offer free ground shipping on every purchase of $300 and more for US and US territory. Please choose "Free Ground Shipping (UPS/USPS)" option at checkout.
UPS Ground
UPS provides up-to-date tracking information. Ground service takes anywhere from 2-7 working days for delivery depending on destinations. UPS Ground does not deliver on Saturdays, Sundays or Holidays.
USPS Priority Mail/USPS Express Mail
For all shipments shipped via USPS, we offer 'DELIVERY CONFIRMATION' number with each package. Difference between tracking number provided by UPS vs USPS Delivery Confirmation number is: Delivery Confirmation status is updated when the delivery has been made or when the package has made it through major USPS stations.
Air Shipment
Air shipments, Overnight, 2nd day and 3 day select methods offer guaranteed delivery time for your shipment. If you are in hurry or in need for the items on schedule, select one of these methods. Up-to-date tracking information is provided with each Air Shipment. AVProSupply has the right to choose between Air shipments to meet or reduce delivery time. For guaranteed delivery of multiple items with expedited shipping, please contact our customer service representative for personalized assistance to get your items delivered to you when you need them.
International Customers
We offer shipping via USPS/UPS for our international customers. You can find different shipping options during checkout.
Most items ordered from AVProSupply will be shipped out from our California Warehouse. Will-Calls are only allowed with Appointment Only - Please call Customer Service to set one up between the hours of 9am to 6pm PST.
We Offer A 30-Day Money Back Guarantee:
Our main goal is to ensure your complete satisfaction with our service and products. If, for any reason, you are not 100% satisfied with your purchase, you can return it within 30 days of the purchase date for a full refund. Our 30-day money back guarantee applies to all of the products we sell, except for: TVs and monitors 20" and larger, Special Order merchandise, or any item indicated as non-returnable. Shipping is not refundable. Prior to returning your purchase, a Return Merchandise Authorization (RMA) number will be provided to you.
Refunds:
Refunds on returned items will be issued in the same payment form as received from the customer at the time of purchase. Once we receive the product and it passes inspection, we will credit your account. Please allow 3 - 6 business days for a credit to appear on your account.
Exchanges:
If the item was sent back to us for an exchange, please allow 3 - 5 business days for the replacement to be processed.
No Returns/Exchanges on the following:
- TVs and monitors 20" and larger
- Special Order merchandise
- Any item indicated on the website as non-returnable
For more information see our official Return Policy
