KGUSS Topping L70 Fully Balanced NFCA Headphone AmpManuale utente lifier

1. Introduzione

The KGUSS Topping L70 is a high-performance fully balanced NFCA headphone amplifier e preamplifier designed for audio enthusiasts. It incorporates advanced NFCA (Nested Feedback Composite Amplifier) modules, offering exceptional audio fidelity with ultra-low distortion and a wide dynamic range. The L70 supports various headphone connections, including 4-pin XLR balanced, 4.4mm balanced, 6.35mm single-ended, and 3.5mm single-ended outputs, making it compatible with a broad range of headphones and in-ear monitors (IEMs).

This manual provides detailed instructions for setting up, operating, maintaining, and troubleshooting your Topping L70 amppiù vivace.

Immagine 1.1: anteriore view of the Topping L70 Headphone Amplifier, displaying its minimalist design with a volume knob, input selection button, and headphone jacks.

2. Caratteristiche principali

• Ultra-High Performance NFCA Modules: Utilizes NFCA (Nested Feedback Composite Amplifier) technology for excellent DC and AC performance, ultra-low THD+N, and a dynamic range of 146dB.
• Fully Balanced Output: Compatible with 4-pin XLR balanced, 4.4mm balanced, 6.35mm single-ended, and 3.5mm single-ended headphone jacks.
• Wide Headphone Compatibility: Volume ad alto rendimentotage and current drive high impedance and low impedance headphones, while low output noise ensures clear sound for sensitive IEMs.
• Cuffia Amplifier e preamplifier Functionality: Functions as both a powerful headphone amplifier and a high-performance preamplifier with suitable output impedance for various power amplificatori.
• R2R Volume Control: Features a precise R2R volume control composed of relays and resistor networks, offering longevity and complete channel balance.
• Ground Loop Noise Terminator: Includes a GND/LIFT switch to address ground loop noise when multiple devices are connected.
• 12V Trigger Interface: Allows synchronized power on/off with other compatible devices, such as the Topping E70 DAC.

Image 2.1: Rear panel of the Topping L70, showing various input and output connections including XLR, RCA, and the 12V trigger interface.

3. Istruzioni per l'installazione

3.1 Contenuto della confezione

Prima di procedere, assicurati che tutti gli articoli siano presenti nella confezione:

• Topping L70 Unit
• Telecomando
• Cavo di alimentazione
• Adattatore da 6.35 mm a 3.5 mm
• Manuale d'uso
• Scheda di garanzia

Image 3.1: Illustration of the Topping L70 package contents, showing the main unit, remote control, power cable, adapter, and documentation.

3.2 Connecting the L70

1. Collegamento elettrico: Connect the provided power cable to the L70's power input and then to a suitable AC power outlet. Ensure the power switch on the rear panel is in the OFF position before connecting.
2. Ingresso audio: Connect your audio source (e.g., DAC, CD player) to the L70's input ports. The L70 supports XLR and RCA inputs. Use high-quality cables for optimal performance.
3. Uscita cuffie: Connect your headphones to the desired output jack on the front panel (4-pin XLR, 4.4mm balanced, 6.35mm SE, or 3.5mm SE).
4. Preamplifier Output (Optional): If using the L70 as a preamplifier, connect its XLR or RCA outputs to your power ampdiffusori acustici o attivi.
5. Trigger 12V (opzionale): If you have a compatible device (e.g., Topping E70) with a 12V trigger, connect it to the L70's 12V Trigger IN/OUT ports for synchronized power control.

Image 3.2: Close-up of the L70's rear panel inputs (XLR and RCA) and various cable types for connection.

4. Istruzioni per l'uso

4.1 Accensione/Spegnimento

After all connections are made, flip the power switch on the rear panel to the ON position. The L70 will power on. To power off, flip the switch back to OFF.

4.2 Selezione dell'ingresso

Press the "SEL" button on the front panel or use the remote control to cycle through available input sources (XLR, RCA).

4.3 Controllo del volume

The L70 features an R2R volume control for precise adjustment. Rotate the large knob on the front panel or use the volume buttons on the remote control to adjust the listening level. The display will show the current volume level in dB.

Immagine 4.1: Interno view of the L70's R2R volume control and a diagram showing volume memory settings for different outputs.

4.4 Impostazioni di guadagno

The L70 offers two gain settings to accommodate various headphones and IEMs:

• Uscita bilanciata: Low Gain 6.0dB, High Gain 19.8dB
• SE Output: Low Gain 0dB, High Gain 13.8dB

Adjust the gain setting via the menu to match your headphones' sensitivity and desired listening level. Lower gain is suitable for sensitive IEMs to prevent background hiss, while higher gain provides ample power for demanding headphones.

Image 4.2: The L70 connected to different types of headphones, illustrating its versatility and the available gain settings.

4.5 preampModalità lifier

The L70 can function as a high-performance preamplifier. When in preamp mode, it delivers the same audio quality as the headphone amplifier mode. The 20ohm SE and 40ohm balanced output impedances are suitable for various power amplificatori.

Image 4.3: The L70 positioned with a pair of active speakers, highlighting its use as a preamppiù vivace.

4.6 Ground Loop Noise Terminator

If you experience ground loop noise when connecting multiple devices, use the GND/LIFT switch on the rear panel. In normal use, set it to GND. If noise occurs, switch it to LIFT to terminate the ground loop.

Image 4.4: Close-up of the L70's rear panel, indicating the GND/LIFT switch for ground loop noise termination and the 12V trigger ports.

4.7 12V Trigger Interface

The 12V Trigger IN and OUT ports allow the L70 to synchronize power on/off with other compatible audio devices. Connect a 3.5mm cable between the L70 and the other device's 12V trigger ports.

Image 4.5: Close-up of the L70's rear panel, indicating the GND/LIFT switch for ground loop noise termination and the 12V trigger ports.

Image 4.6: The L70 stacked with a Topping E70 DAC, demonstrating the 12V trigger connection for synchronized power control.

4.8 Screen Brightness and Output Mode Settings

The L70 allows adjustment of screen brightness and selection of output modes (Headphone Amp, preamp, or both). These settings can typically be accessed and adjusted via the unit's menu system, often by pressing and holding the input selection button or using the remote control.

5. Manutenzione

• Pulizia: Use a soft, dry cloth to clean the exterior of the L70. Avoid using liquid cleaners or abrasive materials, as they may damage the finish.
• Posizionamento: Place the unit on a stable, level surface with adequate ventilation to prevent overheating. Avoid direct sunlight, heat sources, and excessive moisture.
• Gestione dei cavi: Ensure all cables are securely connected and not under undue strain. Avoid sharp bends or kinks in cables.
• Magazzinaggio: Se si conserva l'unità per un periodo prolungato, scollegarla dall'alimentazione e conservarla in un luogo fresco e asciutto.

6. Risoluzione Dei Problemi

This section addresses common issues you might encounter with your Topping L70. For more detailed troubleshooting, refer to the official support resources.

7. Specifiche

Image 7.1: A comparison table highlighting key specifications of the L70 against other Topping models, including amplifier type, inputs, outputs, and power.

8. Garanzia e supporto

This product is sold by HIFI College, an authorized distributor. They offer the following:

• Garanzia di rimborso di 30 giorni per qualsiasi motivo.
• Garanzia di oltre 12 mesi su tutti i difetti di qualità.
• Supporti Garanzia di prezzo entro 30 giorni.
• Responsible for repair and shipping costs for more than 1 year quality restoration.

For any questions or support, please contact HIFI College directly via email at HIFICOLLEGE@gmail.com.