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Radial J+4 2-channel Signal Level Driver

Signal Driver with Level Matching from -10dB to +4dB
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Item ID: JPlus4Stereo
Radial J+4 2-channel Signal Level Driver
Price:$289 and 99 cents
$49.00 suggested monthly payments with 6 month financing‡ 36 month financing available* with $399.00 minimum purchase on one invoice.

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Radial J+4 2-channel Signal Level Driver
In Stock!
Price:$289 and 99 cents
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Your Swiss Army Knife for Level Matching

If you interface pro audio with low-level devices - instruments, MP3 players, computers, etc. - you need the Radial J+4. The J+4 takes incoming signals as low as 10dB and boosts them up to +4 for use in professional audio environments such as recording and broadcast studios or live touring. The J+4's 100% discrete circuitry ensures optimal signal integrity, while its active signal buffering and transformer isolation virtually eliminate noise. The simple control set includes a stereo gain control, a highpass filter, and a ground lift. For flexibility, J+4 is fitted with dual 1/4" and RCA jacks, and an 1/8" stereo TRS input.

Built Radial tough

Like every Radial product, the J+4 is designed tour-tough. At Sweetwater, we expect nothing less from Radial. Its roadworthy 14-gauge steel I-beam inner frame protects the vulnerable PC board, while the unique book-end outside shell puts the controls, switches, and connectors in a protective zone. The bottom is covered in a non-slip pad for superior electrical and mechanical isolation. With its high headroom, ultra-low-noise performance, rock-solid dependability, and amazing versatility, you'll find the Radial J+4 to be indispensable.

Radial J+4 Balanced -10dB to +4dB Signal Driver Features:
  • Increases gain of low-output instruments, computers, and music players
  • Onboard stereo preamp boosts low-level signals to +4dB line level
  • Transformer isolation eliminates noise due to ground loops
  • Generous connectivity:
    • 2 x 1/4" jacks
    • 2 RCA jacks
    • 1/8" stereo TRS
  • S/N ratio: greater than 95dB
Solve your level-matching problems with the Radial J+4!

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Tech Specs

  • Type: Stereo Preamplifier
  • Channels: 2
  • Ground Lift: Yes
  • Outputs: 2 x XLR
  • Analog Inputs: 2 x 1/4", 2 x RCA, 1 x 1/8"
  • Power Supply: 15V DC power supply (included)
  • Height: 2"
  • Width: 3.3"
  • Depth: 5"
  • Weight: 1.55 lbs.
  • Manufacturer Part Number: R800 8015

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Reviews

Radial J+4 2-channel Signal Level Driver
It gives a good signal boost to the speakers. It can be used with phono connectors, 1/4 inch, and XLR connectors. It can be used with balanced or unbalanced lines. I use this on my speakers. I recommend this product.
Radial J+4 2-channel Signal Level Driver
This signal driver gave me a clean sound. There wasn't any hum noise. It boosted my audio signal and did not have to drive the audio signal on the mixer above a normal operating level. I had plenty of signal gain without ring and feedback. This unit doesn't take up much space. This I like. I appreciate this recommendation.
Radial J+4 2-channel signal level driver
I needed to boost a -10dB signal up to +4dB to match a TASCAM product to my Alesis 9600 input. Also, the output from the TASCAM was Hi Z unbalanced and the Alesis had Lo Z balanced inputs. The Radial J+4 worked perfectly. And, like all Radial products, it is built like a tank, rugged, well designed and practical. I can recommend this and all the other Radial products without reservation.
It worked
It did what I wanted. I was able to boost weak signals coming from built DI/line outs on two amps and bring them in to a mixing board as balanced signals. Adds a lot of wires to our set up but makes sound check go a lot faster.
Yes!
I am running a yamaha P515 piano into a set of studio monitors and the output on the piano is unbalanced. So the J4 changes the unbalanced signal to a balanced signal plus gives me plenty of gain to crank up the volume! A regular passive DI box would not work for me...