Nobsound NS-08E User manual

1. This is tube headphone amplifier that can greatly improve the sound quality for
headphones, but also can be used as tube preamp, its 3.5mm headphone jack
also can connect amplifier or active speakers.
2. Default 6J3 vacuum tubes, also can be directly replaced by the following models
6J1, 6ж1П, 6AK5, 6BC5, 403A/B, 5654, EF95, CV850, 6J2, 6ж2П, 6AS6, CV2522,
CV4011, 6J3, 6ж3П, EF94, CV848、6BC6, 6AG5, 6J4, 6ж4, 6136, 6BX6, 6AC7,
6AU6, 6J5, 6ж5П, CV2521, 6F36, 6AH6, 6AN5, 6K4, EF93, 6K5, 6K4П, 6BA6,
6DA6, 5749.
Warm Tips
NS-08E Mini Tube Headphone Amplifier
User Manual
How to Use
Nobsound
1. Connect audio source such as phone, MP3, TV, tablet, computer, CD player etc.
to 3.5mm AUX input of NS-08E, and connect headphone or power amplifier or
active speaker to its 3.5mm output. Recommend high-quality 3.5mm cable.
2. Connect power adapter to NS-08E and then connect power adapter to the socket.
3. Press the red button on the back panel to power it on and warm up for a while.
4. Play music on your audio device, and rotate the volume control to adjust the
volume until perfect and enjoy HiFi music.
Parameters
Audio input: 3.5mm AUX
Audio output: 3.5mm headphone jack
Max output power: ≥1100 mW (32 ohm)
Matched Headphone impedance: 18-600 ohm
Frequency Response: 20Hz - 30KHz
THD: <0.005%
SNR: ≥110 dB
Power supply: DC 6V /2A

Contact Information
Website: www.doukaudio.com
Email: [email protected]
WeChat/Whatsapp: [phone]
Address: Room 1329, Wang Cheng Building, Long Guan East Road,
Long Hua District, Shen Zhen, Guang Dong, China, 518000

1. Not inlcude power adapter, recommend to use original high-quality power adapter (DC5V/≥2A ).
U10 won't work normally if the current below 2A.
2. Inputs (3.5mm / RCA) and outputs (6.35mm/3.5mm jack) are connected in parallel, in other
words, all inputs and outputs work simultaneously. Don't connect 3.5mm and RCA inputs at
the same time, or else audio signals will be mixed.
3. Pluggable tube socket design, 6A2 can be replaced by the following models:
6J1、6ж1П、6AK5、6BC5、403A/B、5654、EF40、EF95、CV850、6J2、6ж2П、6AS6、
CV2522、EF11/732、CV4011、6J3、6ж3П、EF96、CV848、6BC6、6AG5、 6J4、6ж4、
6136、6BX6、6AC7、EF94、6AU6、6K4、6K5、6K4П、6BA6、6DA6、EF89/93、5749.
4. U10 can easily drive all headphones even with high-impedance such as HD580/HD600/
HD650/ K701/K702/Q701 / DT880/T70/T90 / SR225/SR325/RS1e etc.
Warm Tips
U10 Mini Tube Headphone Amplifier
User Manual
Introduction
U10 mini headphone amplifier, with stereo 3.5mm AUX and RCA inputs and dual headphone
jacks (3.5/6.35mm) output up to 1100mW, easily to drive all 18-600Ω headphones; Innovative
built-in voltage boost circuit, U10 always works at a high voltage of 24V even only powered by
DC 5V, 2PCS 6A2 tubes are adopted to soften and warm the audio, both tubes and op amps
use pluggable sockets, convenient for tube rolling, op amp upgrading and sound-shaping.
How to Use
1. Connect the power adapter and U10 via the default USB to DC cable firstly,then insert power
adapter to the socket.
2. Connect 3.5mm or 6.35mm headphone to the output of U10.
3. Correctly connect your audio source to the corresponding inputs of U10 amp with high-quality
3.5mm AUX cable or RCA cable.
4. Clockwise rotate the main knob to turn U10 on.
5. Play music on your audio source, you can turn up or down volume via volume knob.
6. After use, please anti-clockwise the knob to the leftmost end until U10 is turned off, then
disconnect the power adapter.

Contact Information
Parameters
Front and Back Panel
Brand: Douk Audio
Model: U10
Audio input: 3.5mm AUX / Stereo RCA
Audio output: 3.5mm / 6.35mm headphone jack
Frequency response: 20Hz-30KHz
Output power: ≥1100mW (32Ω)
Matched headphone impedance: 18-600Ω
Signal to noise ratio: ≥110DB
Input voltage: DC 5V (≥2A)
Working voltage inside: DC 24V
Dimensions (W*D*H): 95mm*69mm*30mm
/ 3.74in*2.72in*1.18in
Net weight: 200g / 0.44lb
Website: www.doukaudio.com
Email: [email protected]
WeChat/Whatsapp: [phone]
Address: Room 1329, Wang Cheng Building, Long Guan East Road,
Long Hua District, Shen Zhen, Guang Dong, China, 518000
6.35mm / 3.5mm output
Power switch /
Volume knob
DC 5V IN
RCA / 3.5mm AUX input