TOPPING D90SE Updates to D90 III Discrete

[rickmcinnis]

Not sure anyone is interested in this but ...

Opened up the Discrete Sunday - fairly easy to disassemble with a long M2 allen key - almost impossible to replace the screws that hold on the front panel which I have no intention of doing.

Not a MEANWELL supply - or if it is it is not incased. There are three rails - 5 volts which I assume for the digital stuff and plus 8.1 volts and minus 8.6 volts. Seems like those two voltages are unusually far apart for the typical plus/minus supply but then this is a switcher and not a deluxe one so this could be acceptable voltage tolerance. There are regulators past them to take care of the voltage needed, One wonders if the negative rail has other uses? Who knows? I will open my other one and see how similar the voltages are.

After a failed experiment using 3 200aH LiPo batteries and inverters for AC power I have these batteries. I have been using two of them in parallel to power a MUTEC MC3+USB and an RME ADC. My thoughts are why not use them to power the Discretes, also? Seems simple enough to remove the switcher and using 7805, 7808 and a 7908 to bring the voltage down. One would think getting the AC out of that little box would have to be worthwhile and it is easy enough to try.

The DAC is so good I figure one should see what might happen with purer DC.

 

[Chardonnay]

I'm wondering if you took any photos of the Discrete with its clothes off cover removed??

 

[Lexington99]

I'm wondering if you took any photos of the Discrete with its clothes off cover removed??

 

[rickmcinnis]

That's why I did not take any knowing those were around. Along with being a bad photographer.

Mainly wanted to find out the voltages.

After the switcher there are lclc filters after the 8 volts rail but only an lc for the 5 volts rail.

I am thinking I will go with SALAS Ultra_BiB shunt regulators - might as well do it as good as possible. Will have to cut a hole in the enclosure to connect them.

I will bypass the post SMPS filters. Shunt regs do not need or want those filters in the path.

The thing sounds so good my curiosity has to know how they will sound without AC in the box along with the fact that the SMPS looks to be rather ordinary.

 

[felix37]

Just curious if there are any components in the main PCB board under the dac board
If you have both the rme adi and the d90 discrete which wins for SQ ?

​

 

[skasundr]

Apos got back to me with a response from Topping requesting details on my testing with DSD Bypass On and asked for a video of it so I recorded one to show them the hiss with Bypass On and lack of hiss with Bypass Off. Apos didn’t provide any response on exactly what DSD Bypass is supposed to do on this DAC so I reiterated the question when I sent over everything Topping was asking for.

-Ed

Any updates from Apos/Topping?

 

[Edward Ng]

Any updates from Apos/Topping?

I knew I forgot to post their response somewhere (am on multiple forums discussing this DAC):

-Ed

 

[rickmcinnis]

felix37,

I have never listened to the RME as a DAC - only as ADC to convert LP to 24/96 and when I use REW for measurements.

 

[Lexington99]

Who else is waiting for their D90 III Discrete?


I am surprised that not more people have reviewed it so far. It's been out like 2 months?

 

[felix37]

Hope to receive my dac next week

 

[droptables]

Who else is waiting for their D90 III Discrete?


I am surprised that not more people have reviewed it so far. It's been out like 2 months?

I ordered one the other day. Generally not a huge fan of topping but this one looked interesting. After reading the impressions here and the minimal reviews that are available. I decided to give it a shot. We will see what I think. Apos has a 45 day return policy so there is that as well.

 

[Chardonnay]

Mine has been shipped. Waiting for delivery next week.

 

[rickmcinnis]

Opened up my second Discrete and the rail voltages are the same for those who want to tinker. -8.6 volts must be intentional. I wonder if this rail powers the DC-DC converter for the 12 volts trigger?

Gave up on the battery idea since I did not feel like dealing with relays to turn it on.

Luckily the SALAS shunts regs have easily adjusted voltage.

 

[theeclone]

Welp, I ordered one. $849 with 4 interest free paypal payments was too hard to resist.

I'm coming from the holo spring 1 & 2, both KTE, previously the PS Audio DS DAC mk1, and the Schiit Yggdrasil LIM. Will be interesting to see how this stacks up!

 

[Lexington99]

Welp, I ordered one. $849 with 4 interest free paypal payments was too hard to resist.

I'm coming from the holo spring 1 & 2, both KTE, previously the PS Audio DS DAC mk1, and the Schiit Yggdrasil LIM. Will be interesting to see how this stacks up!

With a DAC history like that, I'm surprised you didn't decide to wait for the D900! Hopefully the D90 III Discrete will satisfy your standards.

My unit is in Paris, should have it by Monday/Tuesday.