Chord Electronics Qutest DAC - Official Thread

[Triode User]

Before I start this I want to say that it is not my intention to conclude with a recommendation to buy any particular power supply. I just wanted to see if I could hear any differences between the stock power supply and the ones I tried and also whether I felt that the third party power supplies improved sound quality or otherwise.

Anyway, today I had a play with my Qutest and various power supplies.

Although a Dave is my main system DAC, I have a Qutest in another system and I must say I love its sound. I tend to have it on the Green filter (incisive with HF filter past 20kHz) and that is how it was left for this session.

The Qutest sounds amazing with the Mscaler so this was included in the system. The source was an Innuos Statement connected by USB (Sablon 2020) to the Mscaler.

The Qutest output voltage was set to 3v and the Qutest was connected to a Music First Audio Classic V2 silver wound TVC passive preamp for volume conrol. The preamp connects to Pass Labs XA60.8 mono power amps which drive Spendor SP200 speakers.



I have been swopping between the supplies on an adhoc basis for a few days but today I settled down for a more structured session.

In this session I was really looking for fairly clear and simple indicators to differentiate between the power supplies. Things such as whether the top end is more/less strident, whether percussive sounds are emphasised, whether there seemed to be more 'space' to the sound or indeed whether everything sounded ‘more lifelike’. To my mind many of these are indicators of RF noise and my inclination is generally to search out the exact opposite sound signature. I also paid particular attention to the bass and whether it seemed fuller or deeper and whether it had more or less detail to bass notes.

The power supplies listened to are pictured below -
1) Factory supplied SMPS.
2) PowerAdd Pilot Pro2 USB 2.1A outlet. approx £120
3) MCRU LPS (base version tested). £235, other options available £350 & £495.
4) Uptone UltraCap LPS-1.2. $470 USD
5) SBooster BOTW MkII with optional Ultra MkII. £420
5) Sean Jacobs DC4 LPS (to the left under the table in first picture). £3,000



The test track I listened to was ' Biscuits' by Fink from the live album ' Wheels Turn Beneath My Feet'. This is a great album. Biscuits has various sounds which can quickly enable one to latch onto differences when making adjustments to a system. But as always one must be aware that a difference can at first be mistaken for an improvement when in reality it is exactly the opposite. For instance there is a repetitive rim tap throughout the track and this can be emphasised by some kit swopping and it is very tempting to think that this emphasis is more 'life like' or more 'realistic' when in reality it is just RF noise artifacts which are being heard and which can (will) ultimately lead to fatigue.

I am sure in my own mind that all the ones I tried have a smoother sound than the stock power supply. In varying degrees they all sounded less aggressive in the treble than the stock one. Sounds such as that rim tap were less 'in your face' and to me the sound was altogether more subtle but with also with more real detail to the shape of the percussive note which can then be heard when the overlaid crap is repoved. The battery was particularly good in this respect but I did feel that its bass performance suffered compared to the other supplies. The others had increasingly smooth top ends as one climbed in cost to the point where the better ones had an even more subtle soft top end than the battery but still with plenty of real detail and also they had a deep and firm bass.

So it is my conclusion that the power supplies I heard did make the Qutest sound different in my system and I am sure that what I heard was an real improvement, especially in the reduction of RF noise artifact induced harshness.

Which did I choose? I personally have decided to go with the Sbooster with the Ultra MkII (the Sean Jacobs DC4 was not a viable option because of the cost and anyway it was borrowed from my Dave power supply!). How much, if anything, anyone else is willing to spend will depend on the perceived added sound quality in their system. In reality I would be happy with any of the ones I tried from the MCRU upwards with the exception of the battery mainly because it is unacceptable to me to have to charge batteries for a home system which is often in use for 12 hours every day. Note however that trying a battery (especially as it can be used for other purposes) is perhaps a good way to get a taste of the smoother top end that I am talking about.

One has also to bear in mind that what I heard in my system may not be heard by other people with their systems. Indeed some may not hear any difference from changing out the factory power supply. Please also bear in mind a health warning that any manufacturer is entitled to disallow a warranty claim if a third party power supply causes damage to piece of HiFi.

The over riding take away from this exercise is that I have renewed respect for the Qutest. It is a miniature gem which punches well above its weight and size.

 

[Zzt231gr]

Before I start this I want to say that it is not my intention to conclude with a recommendation to buy any particular power supply. I just wanted to see if I could hear any differences between the stock power supply and the ones I tried and also whether I felt that the third party power supplies improved sound quality or otherwise.

Anyway, today I had a play with my Qutest and various power supplies.

Although a Dave is my main system DAC, I have a Qutest in another system and I must say I love its sound. I tend to have it on the Green filter (incisive with HF filter past 20kHz) and that is how it was left for this session.

The Qutest sounds amazing with the Mscaler so this was included in the system. The source was an Innuos Statement connected by USB (Sablon 2020) to the Mscaler.

The Qutest output voltage was set to 3v and the Qutest was connected to a Music First Audio Classic V2 silver wound TVC passive preamp for volume conrol. The preamp connects to Pass Labs XA60.8 mono power amps which drive Spendor SP200 speakers.



I have been swopping between the supplies on an adhoc basis for a few days but today I settled down for a more structured session.

In this session I was really looking for fairly clear and simple indicators to differentiate between the power supplies. Things such as whether the top end is more/less strident, whether percussive sounds are emphasised, whether there seemed to be more 'space' to the sound or indeed whether everything sounded ‘more lifelike’. To my mind many of these are indicators of RF noise and my inclination is generally to search out the exact opposite sound signature. I also paid particular attention to the bass and whether it seemed fuller or deeper and whether it had more or less detail to bass notes.

The power supplies listened to are pictured below -
1) Factory supplied SMPS.
2) PowerAdd Pilot Pro2 USB 2.1A outlet. approx £120
3) MCRU LPS (base version tested). £235, other options available £350 & £495.
4) Uptone UltraCap LPS-1.2. $470 USD
5) SBooster BOTW MkII with optional Ultra MkII. £420
5) Sean Jacobs DC4 LPS (to the left under the table in first picture). £3,000



The test track I listened to was ' Biscuits' by Fink from the live album ' Wheels Turn Beneath My Feet'. This is a great album. Biscuits has various sounds which can quickly enable one to latch onto differences when making adjustments to a system. But as always one must be aware that a difference can at first be mistaken for an improvement when in reality it is exactly the opposite. For instance there is a repetitive rim tap throughout the track and this can be emphasised by some kit swopping and it is very tempting to think that this emphasis is more 'life like' or more 'realistic' when in reality it is just RF noise artifacts which are being heard and which can (will) ultimately lead to fatigue.

I am sure in my own mind that all the ones I tried have a smoother sound than the stock power supply. In varying degrees they all sounded less aggressive in the treble than the stock one. Sounds such as that rim tap were less 'in your face' and to me the sound was altogether more subtle but with also with more real detail to the shape of the percussive note which can then be heard when the overlaid crap is repoved. The battery was particularly good in this respect but I did feel that its bass performance suffered compared to the other supplies. The others had increasingly smooth top ends as one climbed in cost to the point where the better ones had an even more subtle soft top end than the battery but still with plenty of real detail and also they had a deep and firm bass.

So it is my conclusion that the power supplies I heard did make the Qutest sound different in my system and I am sure that what I heard was an real improvement, especially in the reduction of RF noise artifact induced harshness.

Which did I choose? I personally have decided to go with the Sbooster with the Ultra MkII (the Sean Jacobs DC4 was not a viable option because of the cost and anyway it was borrowed from my Dave power supply!). How much, if anything, anyone else is willing to spend will depend on the perceived added sound quality in their system. In reality I would be happy with any of the ones I tried from the MCRU upwards with the exception of the battery mainly because it is unacceptable to me to have to charge batteries for a home system which is often in use for 12 hours every day. Note however that trying a battery (especially as it can be used for other purposes) is perhaps a good way to get a taste of the smoother top end that I am talking about.

One has also to bear in mind that what I heard in my system may not be heard by other people with their systems. Indeed some may not hear any difference from changing out the factory power supply. Please also bear in mind a health warning that any manufacturer is entitled to disallow a warranty claim if a third party power supply causes damage to piece of HiFi.

The over riding take away from this exercise is that I have renewed respect for the Qutest. It is a miniature gem which punches well above its weight and size.

Thank you for sharing your thoughts,Nick!

The thing is we disagree on the MCRU psu...In my system it was a tad brighter than the stock psu,which makes it a candidate for RFN modulation.

I will ship it back and I think I will try the Ciunas Suoercapacitor psu.

 

[Jon L]

The over riding take away from this exercise is that I have renewed respect for the Qutest. It is a miniature gem which punches well above its weight and size.

Regardless of what different people experience with their Qutest PS experiments, I do believe the above statement will hold true.
Great work with all the comparisons, which I KNOW to be a lot of work.

The other factor to consider is what power conditioning is used with these power supplies. I often find even bigger sound differences among power conditioners than actual power supplies plugged into them, with my preference being modified double-conversion on-line UPS to regenerate power.

One more option for those wanting to try pure battery PS without internal noisy regulation. Just regular battery, to my ears, sound much better than those battery banks with conversion inside. I made such a thing with 18650 batteries before for another component, which sounded fabulous and lasted a long time (5000 mAHx2), so I think I am going to try this with 1.2V rechargeable AA batteries.
When I measure my Eneloop rechargeable 1.2V AA battery used for photography, it measures around 1.32V, so 4 of them will probably work. Unfortunately, these are only 1900 mAH, but x4 will be 7600, x8 (parallel) will be 15,200 mAH, which will actually last some time.

19733647013_232899f3e8_o by drjlo2, on Flickr

 

[kkrazik2008]

I decided to start reading all 300+ pages of this thread a few days ago, and there is some irony in that the recent discussion on PSU almost reads identical to the several pages found in p. 35-45. With so many other factors affect the audio chain, such as source, amplification, headphones, etc, why do the Chord threads always devolve into the PSU discussion? Maybe build a faraday cage to listen to your music? That should solve emi, RF, etc...

Enough of my unsolicited observations, I do have legitimate questions on using the Qutest as I currently am using the Mojo connected to an OTL and not satisfied with the synergy. I tried an older DAC in my stable, a Musical Fidelity V-DAC II and it was a better combination. I like the Chord sound signature, and looking to upgrade as my Mojo isn’t cutting it with the OTL.

I am genuine in my curiosity of the Qutest as a stand alone DAC connected to an OTL amplifier. There are not only suggestions that the stock PSU is a limiting factor, but also suggestions that the unit is designed not to be paired to a headphone amplifier and the recommendation is the Hugo 2.

The reason for the OTL is to drive the ZMF Verite

What are the thoughts from the collective on my dilemma?

 

[technobear]

When I measure my Eneloop rechargeable 1.2V AA battery used for photography, it measures around 1.32V, so 4 of them will probably work. Unfortunately, these are only 1900 mAH, but x4 will be 7600, x8 (parallel) will be 15,200 mAH, which will actually last some time.

Uh, uh! Oh no you don't.

You can add four cells in parallel to give the same voltage but four times the capacity

- or -

You can add four cells in series to give four times the voltage AT THE SAME CAPACITY


If we could do both, we wouldn't need fossil fuels any more.


So, 4 cells in series will give you 5.28V and 1900mAh capacity.

OK as a trial but for this to really fly you'll need to kick it up a notch or two and use 'D' cells.

 

[uzi2]

Before I start this I want to say that it is not my intention to conclude with a recommendation to buy any particular power supply. I just wanted to see if I could hear any differences between the stock power supply and the ones I tried and also whether I felt that the third party power supplies improved sound quality or otherwise.

Anyway, today I had a play with my Qutest and various power supplies.

Although a Dave is my main system DAC, I have a Qutest in another system and I must say I love its sound. I tend to have it on the Green filter (incisive with HF filter past 20kHz) and that is how it was left for this session.

The Qutest sounds amazing with the Mscaler so this was included in the system. The source was an Innuos Statement connected by USB (Sablon 2020) to the Mscaler.

The Qutest output voltage was set to 3v and the Qutest was connected to a Music First Audio Classic V2 silver wound TVC passive preamp for volume conrol. The preamp connects to Pass Labs XA60.8 mono power amps which drive Spendor SP200 speakers.



I have been swopping between the supplies on an adhoc basis for a few days but today I settled down for a more structured session.

In this session I was really looking for fairly clear and simple indicators to differentiate between the power supplies. Things such as whether the top end is more/less strident, whether percussive sounds are emphasised, whether there seemed to be more 'space' to the sound or indeed whether everything sounded ‘more lifelike’. To my mind many of these are indicators of RF noise and my inclination is generally to search out the exact opposite sound signature. I also paid particular attention to the bass and whether it seemed fuller or deeper and whether it had more or less detail to bass notes.

The power supplies listened to are pictured below -
1) Factory supplied SMPS.
2) PowerAdd Pilot Pro2 USB 2.1A outlet. approx £120
3) MCRU LPS (base version tested). £235, other options available £350 & £495.
4) Uptone UltraCap LPS-1.2. $470 USD
5) SBooster BOTW MkII with optional Ultra MkII. £420
5) Sean Jacobs DC4 LPS (to the left under the table in first picture). £3,000



The test track I listened to was ' Biscuits' by Fink from the live album ' Wheels Turn Beneath My Feet'. This is a great album. Biscuits has various sounds which can quickly enable one to latch onto differences when making adjustments to a system. But as always one must be aware that a difference can at first be mistaken for an improvement when in reality it is exactly the opposite. For instance there is a repetitive rim tap throughout the track and this can be emphasised by some kit swopping and it is very tempting to think that this emphasis is more 'life like' or more 'realistic' when in reality it is just RF noise artifacts which are being heard and which can (will) ultimately lead to fatigue.

I am sure in my own mind that all the ones I tried have a smoother sound than the stock power supply. In varying degrees they all sounded less aggressive in the treble than the stock one. Sounds such as that rim tap were less 'in your face' and to me the sound was altogether more subtle but with also with more real detail to the shape of the percussive note which can then be heard when the overlaid crap is repoved. The battery was particularly good in this respect but I did feel that its bass performance suffered compared to the other supplies. The others had increasingly smooth top ends as one climbed in cost to the point where the better ones had an even more subtle soft top end than the battery but still with plenty of real detail and also they had a deep and firm bass.

So it is my conclusion that the power supplies I heard did make the Qutest sound different in my system and I am sure that what I heard was an real improvement, especially in the reduction of RF noise artifact induced harshness.

Which did I choose? I personally have decided to go with the Sbooster with the Ultra MkII (the Sean Jacobs DC4 was not a viable option because of the cost and anyway it was borrowed from my Dave power supply!). How much, if anything, anyone else is willing to spend will depend on the perceived added sound quality in their system. In reality I would be happy with any of the ones I tried from the MCRU upwards with the exception of the battery mainly because it is unacceptable to me to have to charge batteries for a home system which is often in use for 12 hours every day. Note however that trying a battery (especially as it can be used for other purposes) is perhaps a good way to get a taste of the smoother top end that I am talking about.

One has also to bear in mind that what I heard in my system may not be heard by other people with their systems. Indeed some may not hear any difference from changing out the factory power supply. Please also bear in mind a health warning that any manufacturer is entitled to disallow a warranty claim if a third party power supply causes damage to piece of HiFi.

The over riding take away from this exercise is that I have renewed respect for the Qutest. It is a miniature gem which punches well above its weight and size.

A very interesting comparison. One thing you don't state is what is powering the MScaler. Rob has suggested that the MScaler is more prone to RF noise than the Qutest. I guess that it is powered the same way with all the tests and I'm sure with all the kit you have to hand it is receiving the best possible clean power available.
My post above suggests trying NiMH. If you hear an improvement then go for a mains powered trickle charged capacitor solution like the Ciunas. Does this make sense to you?

 

[uzi2]

Uh, uh! Oh no you don't.

You can add four cells in parallel to give the same voltage but four times the capacity

- or -

You can add four cells in series to give four times the voltage AT THE SAME CAPACITY


If we could do both, we wouldn't need fossil fuels any more.


So, 4 cells in series will give you 5.28V and 1900mAh capacity.

OK as a trial but for this to really fly you'll need to kick it up a notch or two and use 'D' cells.

AA NiMH are commonly available up to 3000mAh, but bigger brands at 2500mAh.I'm not sure what would happen as they discharge and voltage drops to 1.2 per battery and what this would do the Qutest. I'm planning to test them on a Pi4 before investing in LPS

 

[Jon L]

So, 4 cells in series will give you 5.28V and 1900mAh capacity.

I'll just get two 4-cell holders and parallel them for 5.28V at 3800mAH.
I have lots of Eneloop AA's already from photography/speedlites, so 8 AA's at work while another 8 is charged up ready to go

 

[dac64]

I am genuine in my curiosity of the Qutest as a stand alone DAC connected to an OTL amplifier. There are not only suggestions that the stock PSU is a limiting factor, but also suggestions that the unit is designed not to be paired to a headphone amplifier and the recommendation is the Hugo 2.

I'm an extremist, so be careful with what I said below:

I once connected a 2V output CD player directly to a power amp, marantz cd-63 to pass alpeh 5, the sound was unbelievable transparent.

You may try 1V output for a start from Qutest directly to OTL, first with low output CD media.

 

[DecentLevi]

I decided to start reading all 300+ pages of this thread a few days ago, and there is some irony in that the recent discussion on PSU almost reads identical to the several pages found in p. 35-45. With so many other factors affect the audio chain, such as source, amplification, headphones, etc, why do the Chord threads always devolve into the PSU discussion? Maybe build a faraday cage to listen to your music? That should solve emi, RF, etc...

I'm under the impression that most hobbyists who have reached the level of the Qutest have by this point more/less already tackled other areas of their chain such as source components and chosen a favorite headphone and amp, so now time to focus on interesting tweaks to further improve the sound. Just speculation though. And a faraday cage may not do anything with this as we're talking about interference that comes through a wire rather than through the airwaves, if I got it right.

Enough of my unsolicited observations, I do have legitimate questions on using the Qutest as I currently am using the Mojo connected to an OTL and not satisfied with the synergy. I tried an older DAC in my stable, a Musical Fidelity V-DAC II and it was a better combination. I like the Chord sound signature, and looking to upgrade as my Mojo isn’t cutting it with the OTL.

I am genuine in my curiosity of the Qutest as a stand alone DAC connected to an OTL amplifier. There are not only suggestions that the stock PSU is a limiting factor, but also suggestions that the unit is designed not to be paired to a headphone amplifier and the recommendation is the Hugo 2.

The reason for the OTL is to drive the ZMF Verite

What are the thoughts from the collective on my dilemma?

I've compared the Mojo to the Hugo 2 and the improvement was night / day all across the board (can't provide many details as it's been a long time), so the Qutest should be a fine upgrade as it's very similar to the Hugo 2. The PSU may be a limiting factor, but there are options for around $250 shipped such as the Ciunas ISO-PS that can really improve the cost/performance ratio IMO. As for the Qutest not designed to be paired with a headphone amplifier - that's definitely not what I've seen on the forums nor in my experience, also not when visiting the Chord Electronics and vendor booths quite a few times at past CanJams - it's definitely for headphone amps.

 

[DecentLevi]

Are you talking about the battery PSU from Ciunas Audio …. https://www.ciunas.biz/product-page/iso-ps
(...)

My mistake yesterday. No the one I ordered is this one:
https://www.ciunas.biz/product-page/copy-of-supercapacitor-power-supply-dual-voltage-outputs. This one has dual outputs to power two devices and can be built for any required DC voltage (I selected 5v for both of the boxes to the right upon ordering). If you want the same with one DC output you can get this for only 150 EUR:
https://www.ciunas.biz/product-page/5v-supercapacitor-power-supply

Here's a few more important quotes from the owner of Ciunas Audio:
(my) PS is powered by supercapacitors which are very different to batteries - they don't produce charge by chemical reaction for a start & so are very much faster & lower impedance, are far quicker to bring to full charge, don't suffer the lifetime issues that batteries do & aren't damaged by going below a minimum voltage.

(many people) don't realise a very important aspect - direct power from battery or supercap is audibly far superior than when this power is routed through a voltage regulator - all voltage regulators seen to suffer from transient response issues & create dynamic noise when providing dynamic power to devices. This was something I discovered many years ago & my battery PS & now supercap PS are designed in this manner. The battery packs being talked about (on this thread) all have voltage regulators on their outputs & are far inferior sounding. A test of audibility will quickly demonstrate this, not looking at specs.

If anybody wants to read into battery Vs supercapacitor power further, there's info on my website here.

And this guy discovered (many years after I was doing this) how dropping voltage regulators is audibly better by far i.e. using direct battery or supercap power.
A measurement shown here of a highly regarded linear power supply (Allo Shanti) when powering dynamically changing loads VS the same LPS but with supercaps added to the output.

RE the Allo Shanti, I was told that while it's a very good PS, it uses 2 small 10F supercapacitors on its' output for 5v and his use 3 larger supercaps outputting 350F, more than absolutely required giving more energy storage. Another issue reported with the Allo PS is residual power drains into any connected devices which may be a problem, but the ISO-PS isolates the outputs from the supercaps when switched off to prevent that.

 

[GreenBow]

My mistake yesterday. No the one I ordered is this one:
https://www.ciunas.biz/product-page/copy-of-supercapacitor-power-supply-dual-voltage-outputs. This one has dual outputs to power two devices and can be built for any required DC voltage (I selected 5v for both of the boxes to the right upon ordering). If you want the same with one DC output you can get this for only 150 EUR:
https://www.ciunas.biz/product-page/5v-supercapacitor-power-supply

Here's a few more important quotes from the owner of Ciunas Audio:
(my) PS is powered by supercapacitors which are very different to batteries - they don't produce charge by chemical reaction for a start & so are very much faster & lower impedance, are far quicker to bring to full charge, don't suffer the lifetime issues that batteries do & aren't damaged by going below a minimum voltage.

(many people) don't realise a very important aspect - direct power from battery or supercap is audibly far superior than when this power is routed through a voltage regulator - all voltage regulators seen to suffer from transient response issues & create dynamic noise when providing dynamic power to devices. This was something I discovered many years ago & my battery PS & now supercap PS are designed in this manner. The battery packs being talked about (on this thread) all have voltage regulators on their outputs & are far inferior sounding. A test of audibility will quickly demonstrate this, not looking at specs.

If anybody wants to read into battery Vs supercapacitor power further, there's info on my website here.

And this guy discovered (many years after I was doing this) how dropping voltage regulators is audibly better by far i.e. using direct battery or supercap power.
A measurement shown here of a highly regarded linear power supply (Allo Shanti) when powering dynamically changing loads VS the same LPS but with supercaps added to the output.

RE the Allo Shanti, I was told that while it's a very good PS, it uses 2 small 10F supercapacitors on its' output for 5v and his use 3 larger supercaps outputting 350F, more than absolutely required giving more energy storage. Another issue reported with the Allo PS is residual power drains into any connected devices which may be a problem, but the ISO-PS isolated the outputs from the supercaps when switched off to prevent that.

That's interesting. I wonder if it's like the supercaps in the TT2.

Maybe you have effectively made a Qutest TT.

 

[uzi2]

My mistake yesterday. No the one I ordered is this one:
https://www.ciunas.biz/product-page/copy-of-supercapacitor-power-supply-dual-voltage-outputs. This one has dual outputs to power two devices and can be built for any required DC voltage (I selected 5v for both of the boxes to the right upon ordering). If you want the same with one DC output you can get this for only 150 EUR:
https://www.ciunas.biz/product-page/5v-supercapacitor-power-supply

Here's a few more important quotes from the owner of Ciunas Audio:
(my) PS is powered by supercapacitors which are very different to batteries - they don't produce charge by chemical reaction for a start & so are very much faster & lower impedance, are far quicker to bring to full charge, don't suffer the lifetime issues that batteries do & aren't damaged by going below a minimum voltage.

(many people) don't realise a very important aspect - direct power from battery or supercap is audibly far superior than when this power is routed through a voltage regulator - all voltage regulators seen to suffer from transient response issues & create dynamic noise when providing dynamic power to devices. This was something I discovered many years ago & my battery PS & now supercap PS are designed in this manner. The battery packs being talked about (on this thread) all have voltage regulators on their outputs & are far inferior sounding. A test of audibility will quickly demonstrate this, not looking at specs.

If anybody wants to read into battery Vs supercapacitor power further, there's info on my website here.

And this guy discovered (many years after I was doing this) how dropping voltage regulators is audibly better by far i.e. using direct battery or supercap power.
A measurement shown here of a highly regarded linear power supply (Allo Shanti) when powering dynamically changing loads VS the same LPS but with supercaps added to the output.

RE the Allo Shanti, I was told that while it's a very good PS, it uses 2 small 10F supercapacitors on its' output for 5v and his use 3 larger supercaps outputting 350F, more than absolutely required giving more energy storage. Another issue reported with the Allo PS is residual power drains into any connected devices which may be a problem, but the ISO-PS isolates the outputs from the supercaps when switched off to prevent that.

John Kelly is so helpful. I thought I needed 2 units to power Pi4 and Qutest, but he he tells me it has two DC outputs, which should be sufficient to cover both. He has also researched the connectors as I will need micro for Qutest and USBC for Pi4. Looking forward to this...

 

[Zzt231gr]

Guys,I am also ready to buy a super capacitor psu,based on all the great reviews.

Does anyone know where to get a good quality 2.1mm male barrel to micro usb cable here in Europe?The stock cable of this device needs an adapter,which I am not so fond of...

 

[uzi2]

Guys,I am also ready to buy a super capacitor psu,based on all the great reviews.

Does anyone know where to get a good quality 2.1mm male barrel to micro usb cable here in Europe?The stock cable of this device needs an adapter,which I am not so fond of...

They are difficult to get hold of outside of China. I opted for USB A adapters as I have both USBC and Micro USB adapters previously used for OTG from Android phones.