Fosi BT20a Max

[F1Fan72]

https://fosiaudio.com/pages/bt20a-m...up&utm_medium=newsletter&utm_source=aftership

This should be interesting ..

 

[obsessive9119]

Definitely looks good in terms of features.

 

[frogmeat69]

Hopefully @amirm gets one in his hands soon.

 

[Bobby Bass]

Just received their email. Looking forward to reviews. I’ve had a good experience with my ZA3 amp.

 

[Saponetto]

Another sharp divergence from Fosi's style, and that's good.
Performances seems on par with the current standard.

 

[Inertiaman]

The feature set is more thoughtful and refined than most prior Fosi models. Finally some reasonable attention to subwoofer integration, 12V trigger, etc. If one doesn't need TV integration (HDMI etc) or highest end features (balanced inputs, very high power) then this could be a an attractive amplifier for 2.1 systems in particular, especially if it has a low price.

Personally I could live without the Bluetooth features or the second RCA inputs, since I'd have a Wiim upstream, but I understand the value of those for that market demographic. I wonder if a similar "upgrade" to the V3 is planned, aka V3 Max, with 12V trigger, PFFB and sub out w high pass filter.

Hopefully Amir will test and confirm clean implementations on the PFFB, high-pass filter, tone defeat, etc.

 

[GGroch]

Interesting that the Op Amp is a vintage one, the NE5532, and not swappable. I think that is fine, but it is out of step with recent premium amp practice.

They say it was carefully tuned, so perhaps it helps keep the PFFB on track to have a known Op Amp in the loop.

 

[F1Fan72]

Interesting that the Op Amp is a vintage one, the NE5532, and not swappable. I think that is fine, but it is out of step with recent premium amp practice.

They say it was carefully tuned, so perhaps it helps keep the PFFB on track to have a known Op Amp in the loop.

Maybe they’ve realised op amp swapping is snake oil

 

[Joe Smith]

Yeah, this one looks pretty good. Similar featureset to my SMSL AO100 I use in my dining room system, but with physical tone controls and using the 3255 chip instead of the Infineon. Good PFFB implementation etc. Will look forward to seeing this reviewed. I wrote Fosi to see if I could get my hands on one to write a review on other Forums.

 

[MCH]

Pretty neat! I am not a fan of Bluetooth for home use but I love the remote, the tone controls, the supposed load independency, the HPF etc etc.
Things that I kind of not understand (@Fosi Audio ): Once there is a remote, it would be neat to have the tone controls available in the remote as well, which I guess they are not because those are not motorized.
Also, I really appreciate the motorized knob (finally!), but a small display would suffice + would make it easier to solve the previous comment.
Nitpicking, I know, good luck with your new product.

 

[GGroch]

Maybe they’ve realized op amp swapping is snake oil

I'm 72, so for my hearing PFFB is snake oil too. Its an interesting choice.

....Once there is a remote, it would be neat to have the tone controls available in the remote as well, which I guess they are not because those are not motorized.
...

My experience with the Fosi MC331 which has non-motorized tone control knobs AND remote tone controls was not neat at all, it was why I got rid of it. . See my 4th & 5th posts here.

I agree full remote control of everything is great when done right, the Ampapa D1 does it all pretty well and has a display showing your settings.

With a good display and a well calibrated digital control knob, I see no real benefit to motorizing the control.

The BT20 Max looks great though and I think it will be a big seller.

 

[MCH]

My experience with the Fosi MC331 which has non-motorized tone control knobs AND remote tone controls was not neat at all, it was why I got rid of it. . See my 4th & 5th posts here.

Oh no!

 

[Joe Smith]

The digital volume control on the SMSL AO100 (not motorized, but changeable via knob or remote, with persistent level through power off/power on and the ability to blank the display) is one of my favorite things about the unit. And, since I mostly use that at quite low volume levels, using the iPhone/Spotify Connect to BT is perfectly fine quality-wise.

The other nice thing this new Fosi has is TWO inputs as well as BT. Right now, in the dining room, I hard-swap the RCA cables between CD and cassette when not using BT. (I realize I'm odd in using cassettes occasionally.)

My only real quibble about the AO100 is that it's a little under-powered for the few times I want to play louder, even when paired with my KEF 6 ohm nominal speakers. Due to the Infineon chip? Maybe.

 

[F1Fan72]

I’m still surprised @Fosi Audio has not made a full width amplifier..

 

[Schlippwhip68]

I wouldn’t be surprised at all if the Douk Audio A5 equipped with opa828 would blow it out of the water for clarity and tonal value especially in the low frequencies….if you know the opa828 you will know exactly what I am talking about. Feed that A5 with a Muses 02 based dac and done…just my penny as they say….and nice that they have included this on the same remote as the P4 and ZP3 which are all different looking machines…bit of square there and curve here dear….forward thinking in design would be an attractive quality to grasp and I think HR dept should have their eyes open a little wider….leaving very little breathing space in these designs is adding to the general patina of a ‘throwaway product’ which eventually most seriously people will grow tired of quickly and look elsewhere especially if certain parts can only be replaced with an larger equivalent, it’s an issue I am currently having with an capacitor that arrived with dents. For the sake of 2mm the whole design of the amp is out of sync because the casing is packed so close to the internal caps and board.

Currently some parts that most of these brands maybe NOS which is ok but if that is the case then it would make sense to compensate for replacement parts that are current or at least complimentary in regard to brand quality if jumping from Rubycon to Nichicon for example which in regard to an 63v 3300uf cap there is a 2mm difference in diameter with the closest match. It would not harm the unit using if 5mm clearance was implemented on the edges and top of the unit, just saying….

 

[solderdude]

I wouldn’t be surprised at all if the Douk Audio A5 equipped with opa828 would blow it out of the water

 

[SlowJim]

 

[Schlippwhip68]

View attachment 501970

….lol.

 

[F1Fan72]

View attachment 501970

Lol

 

[Svend P]

Maybe solderdude has cracked the code to explain the differences between opamps: