[motu81]

My wa33ee broke just as I was going to test the modded dave/mscaler combo. It will take a month or so for me to send it to the US to get it fixed. I can take the dave combo home to try on my home rig though, but there also waiting for my DIY T2 to get back from servicing. Will report back soon with impressions of modded Dave/Mscaler on Taiko Extreme and on Wadax Reference Server.

 

[Mr X]

Being a bit of a Chord fan I've been a long time admirer of @Reactcore's work after stumbling across his posts in the Dave thread which then led me to this thread and also his amazing one on the M Scaler housing!

Anyway the reason I was initially interested in this thread was that I had become more and more intrigued by all the custom mods and claims that people were making about the improvement that can be made to Dave to address some of his shortcomings.

Now I don't claim to be very technical at all but I do believe I have a very good ear and I certainly know what I like the sound of Vs what I don't, they are my ears after all!

I am a very big fan of Dave with my speakers but I've never really enjoyed the headphone element especially and I'm a BIG headphone fan. In fact most of the time I much prefer the sound of my Hugo2 with my Meze Elites or Focal Stellia.

I just find the sound from Dave Headphone Dac to be very thin and non engaging and lacking the dynamics I crave to give me more emotion! Hence reading more and more about what some mods can do particularly the ones that involve changing the stock caps in favour of larger ones.

So when I knew I had to travel to the Netherlands on business I contacted @Reactcore and asked if I could visit and bring my stock Dave to compare to his (It was also a great excuse to see his Scaler housing creation in the flesh!) he very kindly said yes!

So last week I arrived with my stock Dave and we immediately got down to some testing.

First of all his explanation of his own journey and how he had reached this stage AND the reason why, really helped my understanding and knowledge. I also found the way he explained all this to a layman like me to be extremely helpful and I leaned so much from him of which I am very grateful.

Anyway I could go on forever but lets cut to the chase... The sound!

Sadly as Dave took up a lot of space in my bag I wasn't able to travel with my Elites and their rather large fight case. So as I put on his customs H800, which incidentally sounded extremely detailed following his mods to those, the difference was 100% immediate and I was a bit shocked that it was so obvious compared to mine,

I had never experienced this much joy before listening via headphones on Dave in the 3 years I had owned one,

First the transparency and magic that the Mscaled Dave brings is still there but there was now that slam, dynamics and fast energy that I felt was missing was all there, and some. It seemed effortless and so detailed with the mids and sub bass both extremely clean, textured and refined. Relaxed and smooth but just enough warmth and fun.

Now after considerable time listening, I plugged the very same headphones and the same tracks into my Stock Dave, again with Mscaler. I instantly disliked it, more so than ever before because now my ears were coming from a different place. In fact the negative in this whole experiment was that I actually said I now done't like my Dave! By comparison it was even more thin than I remembered and side by side listening at same volumes, It was evduient that I was having to turn the volume louder on my stock to try and retrieve more or equal detail by comparison.

I could go on for ages (as I already have) but in short it was apparent that the caps, additional resistors, optical link and potmeters - basically all the work that has gone into addressing the power and RF issues, really does turn StockDave into super Dave.

I haven't even gone into testing via his fantastic and very capable DIY speakers or the Mscaler housing that I love so much but I have gone away now really understanding how you can improve a great Dac and make it even better IF you know what you are doing and this guy certainly does! I only wish you were closer to the UK so `I could listen more, But for now I'll go back to the UK knowing what I have learned form you and your set up and find someone that can carry out the work for me in London.

Your workmanship and passion of this hobby is amazing - thank you for your time and for the kind hospitality of you and your family for letting me gate crash for a day.


My stock Dave (TOP) Vs SUPERDave

 

[Reactcore]

@Mr X
It was a fun time having you here as its a great joy to share my amazement of the sound change and have what i hear confirmed.

May your Dave now bring you endless musical Bliss. Lol dont forget to sleep as i still have difficulties taking my phones from my head

 

[Reactcore]

So after quite some time using my setup with many wow moments and having made small changes and another addon i post the latest schematic as it is now:

Update 03-04-2024:

The changes are:

• Mod B i managed to find 2700uF ones of the same Chemicon caps to replace the 2200uF ones with the same 8mohm ESR
• Mod D 2x 0,47ohm is changed to 0,22ohm resistors
• Mod F 2x 0,47ohm changed for two linear 1ohm 4W wirewound potmeters placed inside the external PSU housing
• New Mod G added 2x wirewound 10w 47ohm resistors + parallel 4x100pF caps on the mains line of the PSU, this effectively dampens RF and brings even smoother sound with better depth / focus. Ive ordered 22ohm and 30ohm resistors to try to further suppress RF. i will report back when i know more.

 

[Triode User]

So after quite some time using my setup with many wow moments and having made small changes and another addon i post the latest schematic as it is now:

Amazing as always! Totally in awe.

From your schematic I am not sure what you are doing to the 5V digital rail, if anything. I ask because my changing different supplies in and out for the 5V made me conclude that it has a significant influence on sound quality. At least as much as the +/- 15V.

 

[Reactcore]

Amazing as always! Totally in awe.

From your schematic I am not sure what you are doing to the 5V digital rail, if anything. I ask because my changing different supplies in and out for the 5V made me conclude that it has a significant influence on sound quality. At least as much as the +/- 15V.

My experimenting en tests with Sj, Farad and others showed me that the 5v circuit dont benefit from heavy capping or having big currents availabillity in a PSU.

It only benefits from being RF free on its (shared with analog) groundplane.

Its one of the reasons why i stick with the original SMPS.. the filtering.

 

[Triode User]

My experimenting en tests with Sj, Farad and others showed me that the 5v circuit dont benefit from heavy capping or having big currents availabillity in a PSU.

It only benefits from being RF free on its (shared with analog) groundplane.

Its one of the reasons why i stick with the original SMPS.. the filtering.

I compared the 5V with the original smps vs a SJ DC4 and then a SJ ARC6 supply. I was hoping that I could stick with the DC4 on the 5V but unfortunately were very noticeable improvements going to the ARC6 version which was bad for my wallet but really good for sound quality. As well as other differences the ARC6 has a lower noise rectifier circuit compared to the DC4.

 

[Whazzzup]

if you like it you shoulda put a wa 33 EE on it
Don't be mad once you see that he want it

 

[Meridian7]

So after quite some time using my setup with many wow moments and having made small changes and another addon i post the latest schematic as it is now:



The changes are:

• Mod B i managed to find 2700uF ones of the same Chemicon caps to replace the 2200uF ones with the same 8mohm ESR
• Mod D 2x 0,47ohm is changed to 0,22ohm resistors
• Mod F 2x 0,47ohm changed for two linear 1ohm 4W wirewound potmeters placed inside the external PSU housing
• New Mod G added 2x wirewound 10w 18ohm resistors + parallel 100pF cap on the mains line of the PSU, this effectively dampens RF and brings even smoother sound with better depth / focus. Ive ordered 22ohm and 30ohm resistors to try to further suppress RF. i will report back when i know more.

Hi Reactcore,
Have you come to a final mod F potmeter setting or still fidling with? If so, planning to change potmeters for fixed values?

Or a suggested value based on your experiments for those wanting to skip the potmeter installment and going straight for fixed R value?

Mods a to g were chronological.
If one was to implement mods based on their positive impact on sound, how would the order of suggested mods be then?

Thanks.

 

[Reactcore]

Hi Reactcore,
Have you come to a final mod F potmeter setting or still fidling with? If so, planning to change potmeters for fixed values?

Or a suggested value based on your experiments for those wanting to skip the potmeter installment and going straight for fixed R value?

Mods a to g were chronological.
If one was to implement mods based on their positive impact on sound, how would the order of suggested mods be then?

Thanks.

I find myself mostly having the potmeters set around 0,22ohm 1/4 of their 1ohm max.
But if i have an extra harsch recording with that annoying singer ssch in it.. i turn to a higher resistance setting.. but rarely over 0,5ohm

But im more and more aware that i actually like a tiny bit of RF sharpen things.. but staying smooth overall.

I increased the resistors of mod G to 2x 30ohm which made the sound yet warmer/softer (similar but not totally the same effect as higher potmeter values).. the hallmark of less mains RF entering the DAC.

Ive just ordered 2x 68ohm ones to try mod G further. But theres a limit to the value cause of heat dissipation and PSU stabillity so its a matter of balancing.

I guess theres not an order to the mods in the way you see it. When i started with the TDK's i got punchy deep impressive bass but something was off with the midrange.. staying behind.. that got perfectly rectified with the other mods.. so i wouldnt use only a few of the mods (except maybe not doing mod E and C, but disconnect earth in Dave)

Ive recently heard another stock Dave with my headphones and AK DAP source.. and i was shocked how thin and flat it sounded compared to my own.

 

[Meridian7]

I find myself mostly having the potmeters set around 0,22ohm 1/4 of their 1ohm max.
But if i have an extra harsch recording with that annoying singer ssch in it.. i turn to a higher resistance setting.. but rarely over 0,5ohm

But im more and more aware that i actually like a tiny bit of RF sharpen things.. but staying smooth overall.

I increased the resistors of mod G to 2x 30ohm which made the sound yet warmer/softer (similar but not totally the same effect as higher potmeter values).. the hallmark of less mains RF entering the DAC.

Ive just ordered 2x 68ohm ones to try mod G further. But theres a limit to the value cause of heat dissipation and PSU stabillity so its a matter of balancing.

I guess theres not an order to the mods in the way you see it. When i started with the TDK's i got punchy deep impressive bass but something was off with the midrange.. staying behind.. that got perfectly rectified with the other mods.. so i wouldnt use only a few of the mods (except maybe not doing mod E and C, but disconnect earth in Dave)

Ive recently heard another stock Dave with my headphones and AK DAP source.. and i was shocked how thin and flat it sounded compared to my own.

Ok, thank you.

2 Questions left for now:

* have you been considering beefing up the +15 and -15 trajectory (and perhaps grounding) from east to west in the Dave? From PSU part to the regulators part, with e.g. parallel leads on the existing tracing.

* about the MOD F resistors that were changed with potmeters (so before LC circuit) : the resistors were in the + 15V and - 15V leads, whereas the potmeters in the +15V and ground lead, not in the -15V lead anymore. Or is that a drawing error and potmeter should be in the -15V lead too?

 

[Jawed]

Maybe not directly relevant to your implementation, but I found these interesting and fun:



The critical concept explored in the video is that the self-inductance of a capacitor is relevant to switching noise, so a physically smaller capacitor will have less inductance, and so works better to eliminate switching noise. A larger capacitor is better for lower frequency noise.



Here the ferrite bead helps with switching noise but should be combined with the right amount of capacitance, otherwise the switching noise will be worse.

 

[Whazzzup]

For diy out there kudos. But I’ll at least acknowledge analogue internal upgrades are worth it. I just clicked on elite and paid for mine.

 

[Reactcore]

Ok, thank you.

2 Questions left for now:

* have you been considering beefing up the +15 and -15 trajectory (and perhaps grounding) from east to west in the Dave? From PSU part to the regulators part, with e.g. parallel leads on the existing tracing.

* about the MOD F resistors that were changed with potmeters (so before LC circuit) : the resistors were in the + 15V and - 15V leads, whereas the potmeters in the +15V and ground lead, not in the -15V lead anymore. Or is that a drawing error and potmeter should be in the -15V lead too?

Ohmy, youre right. Pot should be in the -15 indeed. Never in ground lead as that would lower the 5v badly. I will update the drawing.

putting extra ground wires in would create groundloops.. not a good idea

 

[Reactcore]

Updated schematic, i will take the other away.

I tried 68ohm resistors at the PSU mains side and it made the sound yet warmer with the same speed and clearness ..but i found the ultra sub bass being less deep reaching,
So i went a step back with 47ohm ones with then 4x 100pF in parallel to short high frequency noise further (can add more caps even) all the bass is back so i found my sweet spot on that i guess. I notice depth and reverb even to modern records i havent heard so easily before.