Should I leave my Qutest, TT2, DAVE or M Scaler switched on all the time?

The practical answer

Yes, for Qutest, TT2, DAVE and M Scaler, by his Head-Fi posts from 2018 to 2023. His general reasoning, in the Hugo 2 thread in March 2018: "it is thermal cycles (on-off heat changes) that damage semiconductors, not keeping things warm" Head-Fi, Mar 2018. In July 2021: "Electronics are more reliable if left on", with standby suggested if power use worries you Head-Fi, Jul 2021. In August 2021 his rule of thumb was to "leave things on for less than 20W" Head-Fi, Aug 2021.

Qutest

In February 2019: "Qutest was designed to be powered up 24/7; it only consumes 2 and a quarter Watts, so don't worry about it" Head-Fi, Feb 2019. In October 2021, giving 2W when on but not processing: "it was intended to leave it on permanently", since its semiconductors run at low temperature Head-Fi, Oct 2021. In January 2018 he gave 2.5W Head-Fi, Jan 2018. Switching off is also fine: in December 2018 he said "you may simply pull the plug on it" Head-Fi, Dec 2018.

Hugo TT2

Around January 2019: "Yes it can be left on all the time, but standby is easy to use (and that shuts down power to the supercaps too)" Head-Fi, Jan 2019. In July 2020: "Yes for sure you can leave it on 24/7 - that's what I do with mine" Head-Fi, Jul 2020. A day later he said keeping it on "actually helps reliability, if you use it every day" Head-Fi, Jul 2020. In August 2021 he gave its draw as 12-13W, said standby on TT2 is fine, and added "If I wasn't lazy I would use standby" Head-Fi, Aug 2021.

Standby keeps the FPGA powered for the remote; in December 2018 he said removing mains power is "perfectly OK", but "I would just use the power switch on the front panel" Head-Fi, Dec 2018.

On supercapacitor life, his figures differ by post, but he called the worry a non issue in November 2018 Head-Fi, Nov 2018, and in July 2020 quoted "500,000 hours for a 50% reduction in capacitance" Head-Fi, Jul 2020.

DAVE

He has said he keeps his Dave on all the time in September 2020, July 2021 and February 2023 ("I always keep it on") Head-Fi, Sep 2020Head-Fi, Jul 2021Head-Fi, Feb 2023. In June 2022 he said the target is a half life exceeding 25 years; likely failures would be connectors plugged in and out every day, and the display, though its failure rate is "extremely low" Head-Fi, Jun 2022. For 25 years of display life, "either set the unit to standby when not in use, or use the message mode on the display (disp 4)" Head-Fi, Jun 2022.

Hugo M Scaler

In November 2018 he answered "Yes you may keep them on - but Hugo M scaler has auto shutdown, and Hugo TT2 has a standby switch", without saying which units he meant Head-Fi, Nov 2018. In October 2019: "It doesn't automatically turn off but enters low power mode", after ten minutes of digital silence on the input Head-Fi, Oct 2019; it "will come out of standby with the first sample of active data" Head-Fi, Feb 2019. In January 2019 he put the FPGA die at only 45 deg C in a stacked setup, which he said would not significantly degrade lifetime Head-Fi, Jan 2019. In March 2023: "You can turn off the Hugo M scaler and turning it back on and it will be fine - there is no warm-up time on the scaler" Head-Fi, Mar 2023.

Does it sound better after warming up?

In May 2018 he said Qutest measures the same even when cold, but "does sound slightly warmer after being on for ten minutes" Head-Fi, May 2018. Around January 2019, TT2 from un-powered takes "about 10 minutes" Head-Fi, Jan 2019; in February 2019, of M Scaler with TT2: "It just needs 10 minutes of warm-up!" Head-Fi, Feb 2019. In September 2020 he said his ten-minute figure came from Mojo and Hugo 2, as his Dave and TT2 are on all the time Head-Fi, Sep 2020. In early 2023 he said the DACs measure identically from cold, and after a hotel-room test with Hugo 2 he put the ten minutes he hears on flights down to his ears and headphones adjusting to cabin pressure Head-Fi, Jan 2023Head-Fi, Feb 2023.

If you also own a Hugo 2 or Mojo

In March 2020, for Hugo 2, he called it "a very marginal call": "if you use it 8 or more hours a day every day, keep it on" Head-Fi, Mar 2020. In July 2024: "If you are not using it for two days or more, I would turn it off, but keep it on otherwise" Head-Fi, Jul 2024. Mojo, he said in 2020, "should be turned off when the charger is connected all the time" Head-Fi, Mar 2020.

What the archive does not show

No figure from him for M Scaler low power mode or DAVE standby turned up. His one TT2 standby figure, "well below 2W", came in May 2018; a week later he said official figures must come from Chord Head-Fi, May 2018Head-Fi, May 2018.

Quotes

“Qutest was designed to be powered up 24/7; it only consumes 2 and a quarter Watts, so don't worry about it.”2019-02-19 Head-Fi, Feb 2019

“Yes for sure you can leave it on 24/7 - that's what I do with mine. If you want to save power then use the standby power down.”2020-07-27 Head-Fi, Jul 2020

“Electronics are more reliable if left on. If you are worried about the 12W or so power consumption, then use the standby - this keeps the clocks running.”2021-07-22 Head-Fi, Jul 2021

“You can turn off the Hugo M scaler and turning it back on and it will be fine - there is no warm-up time on the scaler.”2023-03-01 Head-Fi, Mar 2023

Dated positions

Caveats and open points

• Some TT2-thread post dates are estimated from post IDs, so those dates are given at month level or as 'around'.
• Wattage figures are from Watts's forum posts, not Chord's published specifications, and vary between posts.
• His 'them' in the November 2018 M Scaler thread reply is not identified by the post; it is reported as written.
• Warm-up statements differ across 2018 to 2023 and across products; in 2023 he attributed the effect he had heard on flights to pressure changes on his ears.
• Hugo 2 and Mojo advice is included only as a brief contrast; those battery products are covered by other answers.

Topics: Leaving it on, standby and reliability