Qudelix T71 a portable DAC/Amp for the power hungry!

[maximit]

I was not looking for a portable DAC/Amp as I mainly listen at my computer workstation with my A70 Pro. I recently got two DAC/Amps included in a used headphone purchase I made, a Qudelix T71 and an ifi GO Bar. I just wanted to make this post about how much I love the T71. Its got 8V on high gain, enough to make my HD650 with my crazy high bass EQ shake my head! By my calculation its got over 210mw of power into the Sennheisers, almost as much as the Topping DX3 Pro+ I used to own. I also tried it with some DCA and HiFiMan planars and predictably it was short on current, but for high impedance headphones this thing is awesome. Its got an app in the form of a Chrome plugin. From the app you have dual EQ functionality, primary EQ to flatted out headphones (Oratory for example) and a secondary EQ that I use for bass boost. I also love the amount of info given on display including dual volume (device volume and source volume), output voltage etc. Comparing to the ifi GO bar there is no comparison power wise, even though it claims 7.2v output, to my ears its not close to half of that perhaps mine is faulty. Its bigger than a basic dongle as its got a built in battery for mobile use if your device cant provide enough to power it, it draws 3A when connected to my MacBook. Perhaps a bit on the large size for iPhone use but for my MacBook its perfect.

Not sure about the SINAD on it, but sounds clean enough for casual listening, would love to see it measured.

 

[HELIAS]

I bought the T71 after reading some media and user reviews including this one. I can gladly confirm that it's a powerful amp, with a surprisingly compact size only slightly bigger than the Fiio BTR7 it replaces.

The T71 displays its output level as two decibel values: the device volume, which is the volume of the T71 itself, and the source volume, which is the volume of the phone or computer it is plugged into. They are the two numbers "+6.0, -15.0" shown in OP's second picture. The output VRMS is displayed in the upper left corner above the "+6.0" value.

On low gain, with both the T71 and source device at 100%, the volume numbers show "0.0, 0.0", and the amp outputs 4 VRMS through the 4.4 mm port. This is enough to drive my HE6se at slightly above my regular listening levels, which means I get 5~6 dB's EQ headroom.

For those who want even more volume, the high gain offers an extra 6 dB. At maximum volume (+6.0, 0.0), the amp delivers 8 VRMS. According to Amir's review, the HE6se has a sensitivity of 91.3 dB/VRMS (1370 mV at 94 dB), and an impedance of 64 Ω, so 8 VRMS translates to 109.4 dB.