Which DACs are known to be sweet/rich/relaxed?

This will probably seem whackadoo but Akiko Audio used to make a product called a Squeezebox. I asked an Akiko dealer about it and he said that he uses one with his solid state tuner because it makes it sound like a tube tuner instead. They're not very expensive but I'm not sure how difficult it would be to find one. However, if you could try one out with your DAC, it might reveal whether or not a tube sounding DAC will make any improvements.

Big learning moment!
To see what the impact of my large, mostly untreated living room is, I decided to drag my 374lbs / 170kg Stella Utopia speakers to my bed room :)

I put a few mattresses and diffusers up against the wall, rug on the floor, thick drapes behind the listening position, etc. Photo here: https://ibb.co/PNCzHnW

This well dampened environment made ALL the difference! Old recordings and playing loud no longer caused any harshness or brightness. Room wasn’t dead either: RT60 was around 400-500ms, about half of my living room.

This reminds me that the room is one of the most important components in the chain.

My 13 x 20ft / 4 x 6m bed room is obviously too small for these huge speakers to spread their wings. But it was a great way to prove a point.

This finding prevents me from chasing different gear. I’ll either install more absorption, or simply accept that a large, mostly untreated living room has its down sides.

I spoke only about that for 2 years here.... 😁😊

And what you have changed is ONLY one of the three factors at play imagine the three factors impacts working at the same time ?...

And you put in in place these various materials WITHOUT listenings experiments ...

The first factor below is what people understand to be acoustic treatment...The other two factors are spoken about nowhere in audio forums and in articles...I foundnothing and discovered them one experiment at a time... People call my room the "nut" room... Guess who laugh the last? 😁😋

It is the reason why they upgrade without end, not knowing the acoustic S.Q. vocabulary and experiments protocols of listening and measures...

The most fun time of my life was not buying the gear, it was tuning the system/room like a piano is tuned , one step at a time, using timbre recognition as a meter, and imaging as a second meter, and the most subtle and important one: how is the ratio n listener envelopment/ sound source width or LEV/ASW... Controlling positively , not eliminating all the reflections and the reverberation time is key....

The room modes and zone pressures i used Helmholtz method to tame them...Resonators and diffusers at the right location... The critical point is between 100 to 200 hertz in small room like mine 13 feet square...It is the most difficult to do right...I disconnect my only subs...No need for it with my 7 inches woofer in a controlled room... But my speakers arevery good one for bass for sure...

 

There is 3 main factors in a dedicated room :

 

--- Passive acoustic usual material treatment with a BALANCE between Absorption/Reflection/Diffusion... This is mostly different materials having one of these properties at some critical location in some ratio relative to the room geometry, topology and acoustic content and size...

 

--- Active acoustic mechanical adjustable control with Helmholtz resonators and diffusers at some critical locations of various size proportions..The ratio of the parts is described and easy to find in books or articles on the net, but you can tune hundred of them, with listening experiments few at a times.... They compensate each other but it takes me months of listening fun....

 

--- Psycho-acoustical method where the speaker A and B are dyssimetrically externally treated with resonators and diffusers near them to help the brain figuring out direct waves and reflected one by timing method from the two speakers for ear alpha and beta....In very small room you can easily use a foldable screen with diverse diffusers and absorbing and reflecting devices on it behind your listening position to focus the waves from each speakers more easily for the Brain to create a soundscape that will crush any headphones to pieces and filling the room....Speakers disapear completely in most recording save the mono one ...

The goal of this three factors is transforming the frequency response of the room for the specific speakers needs...i transformed the speakers indirect response by adding diffusers and resonators near them though in a dyssmmetric way for each speakers...

 

This is all i have done at NO COST for the last 2 years...

Upgrading is useless for me and i am even afraid to so call upgrade because of my ratio S.Q. /price over the roof now...

Nothing can replace a room....No price tag....

 

As a complement to Acoustic and psycho-acoustic methods, i used 3 ways for a better ionization of the room and i used a grid of cheap Schumann generators modified...

All my headphones modified with success 8 years ago, so good they were, are now in a drawer...

The 8 headphones cost me more than my basic audio system.... But we learn from our mistakes...

My point is proved: audio experience may cost peanuts...

 

I forgot to add to all this:  You must learn how to control mechanical vibration and the electrical noise floor of the house... With the three acoustic factors above these are very essential...

 I called all that the three  working dimensional embeddings control...Mechanical,electrical and acoustical.... The ionization and the S.G. grid is a plus with all that done...

 

 

Kora Hermes,NOS dual tube output. A gorgeous sounding piece of gear. Switchable output gain 2v/5v great for people with passive pre-amps, like me. And the fun of tube rolling.

I love mine. Almost bought an Audio Mirror until I saw the "under the hood pics" 

looks like it was made in a high school shop class. The Kora is built by French Aerospace engineers, and looks and sounds it!  

SMSL D3 at 3500$.    As relaxed, and as refined as most out there....

Proposed solution / first step
Upgrade to a (tube based) DAC, budget $25-40k.

i have no idea...  but my 2 cents...

with your system, if you have the mola mola dac and there is harshness, getting a different dac isn't the solution