Newbie to the forum and have a question...

[BillG]

Read many a good thing about the Topping D30 and D50 but those have not been described as being "warm" but "detailed".

I agree completely with what's been written about subjective reviews above. Also, a competently designed DAC is meant to be transparent, without a sonic signature of its own.

According to the DSP suite I use on my media player, if I want a "warm" sound its engineers offered a preset that boost the lower frequencies from ~280Hz downwards by 8 dB, while gradually rolling off the highs starting at 10Khz, and slamming them to the floor at 16Khz and above - I never use it...

 

[zermak]

I am with everyone who is suggesting you to try to EQ the sound on your preferences rather than spend money on another (bad implemented if I may say it, considering you don't want a flat frequency response) DAC.
The warm signature of the sound is probably a subjective matter but with a fast search it looks like the 200Hz-ish zone is the one to boost (even our friend @solderdude has his own graph on his site for the sound signatures: here).
As usual room, speakers and so on will impact the sound so as suggested proceed with caution (and if going the EQ way use a negative preamplification to prevent clipping).