FX Audio 6j1 tube preamp - a $31 wonder

[gnat_leader]

This whole thing was a bit predictable/trouble for me lol. I collect golden age comics, then had a couple years in a roman coin phase, even had a rock tumbling phase. As soon as I bought the MC-331 I was off to the races buying different E95/6AK5 class tubes (bulk lots included), rolling weekly to find the magic. Once I started thinking "can this sound even better" I started changing out parts of my chain, first was speakers to Dali Oberon's, then Bluetooth to wifi etc., but didn't want to leave that tube class because I sort of married into it with all these tubes. Coming up with music in late 70s and early 80s, I may have gotten more fond of "warm analog" type sounds than crystal clear clinical. In retrospect, for another $1k I might have just gone WiiM Ultra and Willsenton R8 and been done with it - this hobby makes one a little crazy. Did I make right choice, am I really already thinking of next steps before I even have these steps in the house? I'm committed to take this current "final" set up with FX-TUBE 03J+ when it all arrives at least a solid year and see where my thinking is at then. Presumably, the FX-Tube is a "more tubey" step up over the Fosi-MC331. You mentioned a couple of others - perhaps nothing is a clear "best." Interesting to see so many of these hybrid tube amps out there. As Johnny Fever (I'm old enough to rememer WKRP) hinted at, must be part of the rise of class D amps and want/need to add some warmer flavor overlay.

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Speaking of warmer overlay to Class-D amps some of you might be interested in my FX-Audio Tube-02 Pro (E95/6AK5) preamp mod thread over on DIYAudio.
This is another uber-cheap sorta hybrid buffer preamp but has a more minimalist circuit without any tone controls or opamps. It sounds decent stock but modded it really sings with that tube magic and dead quiet.

 

[path4play]

Nice! Mixing opamps across devices and even within a device is not something I've done. I think every device with opamps I've ever gotten has had that ubiquitous NE4355? from Texas Instruments. Every opamp I tried in replacing them sounded different. Some were brighter, others too smeary... I settled on the Muses, but I may go back and play with the 1656's in conjunction with them to see what happens.

Depending on the overall sound you're going for, the WE tubes are highly thought of. They sound great. No loss of detail and they have that tubey thing about them. The RCA's are similar. The Voskhod Rockets are great too. I used them where I need a little more gain.

Really surprised me. Stock op to Muses02 - I liked it, just a tad thick. OPA1656 to Muses02 - I liked it too, smooth as silk but too pillow cloud soft for me, the sweaty grit and smokey room flavor seemed dropped out. Muses02 to Muses02 actually sounded about like, just the stock op to Muses02 - a little bloomy here and there, but it was not Muses02 squared. Finally, Muses02 to OPA1656 seemed to be just the right thing for my ears and tastes. It was an enlightening experiment.

 

[path4play]

Speaking of warmer overlay to Class-D amps some of you might be interested in my FX-Audio Tube-02 Pro (E95/6AK5) preamp mod thread over on DIYAudio.
This is another uber-cheap sorta hybrid buffer preamp but has a more minimalist circuit without any tone controls or opamps. It sounds decent stock but modded it really sings with that tube magic and dead quiet.

Amazing thread and documentation, thanks for sharing.

 

[lico]

Seriously? LOL.

 

[gnat_leader]

Seriously what LOLLY boy?

 

[lico]

Posted to wrong thread by mistake

 

[path4play]

Really surprised me. Stock op to Muses02 - I liked it, just a tad thick. OPA1656 to Muses02 - I liked it too, smooth as silk but too pillow cloud soft for me, the sweaty grit and smokey room flavor seemed dropped out. Muses02 to Muses02 actually sounded about like, just the stock op to Muses02 - a little bloomy here and there, but it was not Muses02 squared. Finally, Muses02 to OPA1656 seemed to be just the right thing for my ears and tastes. It was an enlightening experiment.

Added the LPS and was quite surprised at the difference. Different perhaps than I expected, but interesting. I felt I could hear the drums come into Chocolate Chip Trip better, the drum hits were all more well defined... Lower noise floor, perhaps tighter. Interestingly, I sense that it boosted the OPA op amp more in the "Muses02 to OPA battle." Even though the dual output LPS goes both to the FX-Tube and ZD3 DAC. Its like I guess, sound waves are actually pretty malleable and it doesn't take too much, even cleaner power through the exact same system to result in a change in the tiniest features of the music.

 

[path4play]

Well, now added CD Hi-Fi streaming.... another boost. Swapping tubes between Western Electrics and the LM Ericsson 5591 403B. Sweet heaven.