Can someone please recommend the correct battery to operate this product

I purchased a 24Vdc@10 amps power supply. A lithium battery supply from parts Express using 5 18650's cells is 21Vdc and would work just fine.

Will it be useful to install a crossover? or is it not necessary?

I have tree of these running Speakers and sub-woofers with no crossover.

does the main volume affect the sub volume or are they completely independent?

The sub volume is not completely independent . I guess it’s kinda like having a gain adjustment on a car stereo amp ..

What is the output wattage using a 12v input at 8 ohms?

12 watts or so. To get 50W you need 24V at about 3.5 amps at 4 ohms.

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ZK-MT21

Product ID: 368986425

Details

Item dimensions L x W x H
4.37 x 4.05 x
Manufacturer
DAJUNGUO
Maximum Supply Voltage
24 volts
Minimum Supply Voltage
12
Voltage
20 volts

🔊50W×2 + 100W subwoofer power

🔋12-24V wide voltage input

🎚️Adjustable treble & bass controls

R$267

Duties & taxes included

In stock

Sold byAmazon BrazilDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

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Description

🎵 Elevate your sound game—power, control, and clarity in one sleek board!

RELIABLE 24 7 SUPPORT - Dedicated customer service ensures your amplifier stays in top shape, anytime you need.
PRECISION AUDIO TUNING - Customize your soundscape with dedicated treble and bass knobs for rich, layered audio.
ROBUST SAFETY FEATURES - Built-in short-circuit, over-current, over-heat, and reverse polarity protection for worry-free performance.
UNIVERSAL CONNECTIVITY - Seamlessly connect via Bluetooth, AUX, or USB—compatible with all your devices, from phones to laptops.
IMMERSIVE 2 1 CHANNEL POWER - Experience crystal-clear stereo with booming 100W subwoofer punch for next-level sound.

The ZK-MT21 Bluetooth Power Amplifier Board delivers a powerful 2.1 channel output with 50W per stereo channel plus a 100W subwoofer, operating efficiently on a wide 12-24V input range. Featuring the high-fidelity TPA3116D2 chip, it offers ultra-low distortion (THD ≤0.1%) and versatile connectivity options including Bluetooth, AUX, and USB. With adjustable treble and bass controls, plus comprehensive protection mechanisms, this compact 4.37x4.05 inch module ensures premium sound quality and reliable, safe operation for all your audio projects.

Specifications

ASIN	B09HKB44JQ
Best Sellers Rank	#19,283 in Electronics ( See Top 100 in Electronics ) #82 in Audio Component Amplifiers
Brand Name	DAJUNGUO
Customer Reviews	4.4 4.4 out of 5 stars (449)
Included Components	amplifier board
Item Dimensions	4.37 x 4.05 x 1.02 inches
Item Weight	130 g
Manufacturer	DAJUNGUO
Maximum Supply Voltage	24 volts
Minimum Supply Voltage	12 volts_of_direct_current
Model	ZK-MT21
Mounting Type	Surface Mount
Number of Channels	2
Package Type Name	Hard Case
Part Number	ZK-MT21
Supply Current	5 A
UPC	194852390669
Voltage	20 volts

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R$267

Duties & taxes included

In stock

Sold byAmazon BrazilDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to Brazil.

Secure transaction

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TrustScore 4.5 | 7,300+ reviews

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