7-Band EQ Preamplifier & Headphone Amp | GUANDO EQ-7
7-Band EQ Preamplifier & Headphone Amp | GUANDO EQ-7
GUANDO EQ-7 | 7-Band Equalizer Preamplifier & Headphone Amplifier
Take full command of your listening experience with the GUANDO EQ-7 — a precision-engineered 7-band audio equalizer preamplifier with a built-in headphone amplifier. Whether you're fine-tuning music on your computer, gaming on a console, or enjoying audio from your phone, the EQ-7 delivers studio-grade tonal control in a compact, easy-to-use module. Made in Mainland China.
Key Features
- 7-Band Equalization (±12dB range): Shape your sound across seven dedicated frequency bands — 60Hz (deep bass), 150Hz (low bass), 400Hz (mid bass), 1kHz (midrange), 3kHz (mid-high), 6.5kHz (high), and 15kHz (ultra-high). Each knob uses a center-zero design: turn clockwise to boost, counterclockwise to attenuate.
- High-Quality Opamp Circuit: Built around the TI/ST TL074 original IC for clean, low-noise equalization across all bands.
- 14dB Preamplifier Gain: A classic 4580 operational amplifier provides 5× signal amplification (14dB), giving your audio source a powerful, transparent boost before it hits your speakers or headphones.
- Versatile Headphone Driver: Dual NE5532 opamps power a Type-47 headphone driver circuit, capable of driving virtually any headphone from 16Ω to 600Ω — from budget earbuds to audiophile-grade over-ears.
- Universal Input/Output: Dual interface support — 3.5mm (3-pole/4-pole) for phone, computer, and headset with mic compatibility, plus RCA Lotus interface for home audio setups. Note: 3.5mm input and RCA input cannot be used simultaneously — select one. Both 3.5mm and RCA outputs can operate at the same time.
- Wide Voltage Range: Operates on DC 5V–12V via a 5.5×2.1mm barrel connector. Compatible with power banks and quality USB charging adapters. Static current: ~390mA at 5V; ~140mA at 12V; total power consumption ~1.8W.
- Compact Form Factor: Dimensions: approximately 11.4 × 8.5 × 3.2 cm — easy to place on a desk or integrate into an audio rack.
Technical Specifications
| Model | EQ-7 |
| Brand | GUANDO |
| Supply Voltage | DC 5V – 12V |
| Power Connector | 5.5 × 2.1mm barrel jack |
| EQ Bands | 7 (60Hz / 150Hz / 400Hz / 1kHz / 3kHz / 6.5kHz / 15kHz) |
| EQ Adjustment Range | ±12dB per band |
| Preamp Gain | 5× / 14dB (4580 opamp) |
| Headphone Output | 16Ω – 600Ω compatible |
| Input Impedance | 20kΩ |
| Output Impedance | 600Ω |
| Audio Interface | 3.5mm (3-pole/4-pole) + RCA Lotus |
| Dimensions | 11.4 × 8.5 × 3.2 cm |
| Country of Origin | Mainland China |
What's in the Box?
- 1× EQ-7 Host Unit
- 1× Power Cord
Usage Tips
- Use a high-quality power adapter or power bank to avoid interference or background noise in the audio signal.
- Start with all EQ knobs in the center (flat) position and make gradual adjustments to dial in your preferred sound profile.
- For headset/mic use on a phone or PC, use a 4-pole 3.5mm plug to retain microphone functionality.
Learn more: ENERGY STAR product efficiency guidance
Frequently Asked Questions
Q: Can I use the EQ-7 with both a phone and a computer headphone?
A: Yes. The EQ-7's 3.5mm input/output supports both 3-pole and 4-pole plugs, making it compatible with standard headphones and headsets with a built-in microphone for use with phones, computers, and gaming devices.
Q: What power supply do I need for the GUANDO EQ-7 preamplifier?
A: The EQ-7 accepts DC 5V to 12V via a 5.5×2.1mm barrel connector. A quality USB power bank (5V) or a regulated DC power adapter works well. Avoid low-quality or noisy power supplies as they can introduce hum or interference into the audio signal.
Q: Can I use both the RCA (Lotus) and 3.5mm inputs at the same time?
A: No — you must choose one input at a time: either the 3.5mm input or the RCA Lotus input. However, on the output side, both the 3.5mm output and the RCA Lotus output can be used simultaneously, allowing you to drive headphones and a speaker system at the same time.
Q: What headphones are compatible with the EQ-7's headphone amplifier?
A: The built-in headphone amplifier uses a dual NE5532 Type-47 driver circuit, capable of powering headphones with impedances ranging from 16 ohms (standard consumer earbuds) all the way up to 600 ohms (high-impedance audiophile headphones), making it extremely versatile.
Production & Packaging Notice
To maintain high stock availability and fast shipping times, our items are sourced from multiple verified manufacturing facilities. While the core quality, materials, and product specifications remain identical, you may notice slight variations in the packaging design, manufacturing origin, or the wording of the printed instructions.