General

Will Leckerton model X work with my headphones/earphones?

All Leckerton amps are designed to drive a wide range of headphones and earphones. They can handle headphone impedances from 16 Ohms to 300 Ohms. They can also drive a high-impedance line level input (10 kOhms, for example), such as the input to a home stereo receiver.

Why not just use the headphone output on my computer/laptop?

Two reasons. First, these outputs tend to be noisy, especially with high-sensitivity headphones or earphones. The computer’s digital-to-analog converter can pick up noise from hard drives, fans, etc. With a Leckerton USB amp, the digital-to-analog conversion is performed outside of the computer, thus avoiding these sources of interference. Second, the analog headphone amplifier circuitry in a typical computer or laptop tends to be underpowered. A Leckerton USB amp can generally provide a signal with more voltage and more current into a wide range of loads, resulting in a cleaner and clearer sound.

How much improvement in sound quality will a Leckerton USB amp provide over the headphone output of my portable MP3 player?

The answer is: it depends on the rest of your gear, including your headphones. On some setups, the improvement is subtle. On other setups, the difference can be quite drastic. A Leckerton amp provides a high-impedance load to the headphone output of your MP3 player. For the most part, your MP3 player can drive a cleaner signal to this high-impedance load than it can to a headphone load. The more difficult job of driving the headphones is left to the Leckerton amp. Keep in mind that the sound quality from any headphone amplifier is only as good as the source material. In other words, don’t expect much improvement with low-bitrate MP3s.

Can I use a Leckerton USB amp as a preamplifier to an A/V receiver or amplifier?

Yes. All Leckerton USB amps can drive a high-impedance load, such as the line input to a receiver or amplifier.

Which gain setting should I use?

Start out with the low-gain setting — this is sufficient in most cases, and it will result in the lowest output noise floor. Use the high-gain setting only if you are unable to get enough output level in the low-gain setting.

USB

Will USB streaming audio work with my operating system?

The USB interface chip used in Leckerton amplifiers is supported in Microsoft Windows 98SE, 98ME, 2000, XP, Vista, Windows 7, Mac OS 9.1 or later, and Mac OS 10.0 or later. It may be possible to use Leckerton amps with other operating systems not listed here (Linux, for example), but compatibility is not guaranteed.

Isn’t USB power too noisy to supply the sensitive audio circuitry of a headphone amplifier?

The audio circuitry in a Leckerton USB amp does not use the USB 5V supply directly. High-frequency switching regulators provide a means of isolating sensitive circuitry from noise which might be on the USB power.

What sample rates are supported with USB streaming?

Sample rates of 32kHz, 44.1kHz, and 48kHz are supported. Sample rate is automatically detected by the amplifier. Supported bit depth is 16 bits for all sample rates.

Am I required to install software/drivers on my computer to enable USB streaming?

No, the USB interface chip in the amp uses the generic USB audio drivers which are built into Windows and Mac OS. There is no additional software or driver to install. All that is required is to select the Leckerton amp as the audio output device in your operating system. For details, see the User Guide for your amplifier.

Are Leckerton amplifiers compatible with the Apple iPad?

Yes, but only the UHA-6S and UHA-6. A special factory modification is required. This modification will allow you to connect the amplifier to your iPad when amplifier charging is disabled. The modification is provided free of charge to all new and existing UHA-6S/UHA-6 owners. Please contact us for more information.

Can I use the iPod Dock Connector to USB Cable to stream digital audio from the iPod to the USB amp?

Unfortunately, no. The only way to stream digital audio to a Leckerton USB amp is to connect it to a USB host, which generally means a computer. To use with an iPod, connect the headphone output of the iPod to the analog input of the amp.

Battery

Is it OK for the battery to leave the amp connected to a USB port all the time?

Yes. You can leave your Leckerton amp connected to USB continuously without damaging the battery. The battery is only being charged when the charging circuit detects that it is not at full capacity. The charging circuit also has several safety features which disable charging in the event of a faulty battery.

How many charge/discharge cycles will I get from the battery?

The Lithium-ion batteries used in Leckerton amplifiers are rated for a lifetime of several hundred complete charge/discharge cycles. If you do not discharge the battery completely every time you use it, this number will be higher. After several years of use, the battery may not hold as much charge as it did when it was new. If desired, it can be replaced with a battery of equivalent size. For details, see the User Guide for your amplifier.