TPA3255 Reference Design Class D Amp with PFFB

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Hi Viet,
a friend of mine has Magnepans (4 ohms) and would be interested in this amp (it means I should build it...), but he thinks he (or the Maggies) need more power, because they are very hungry. So the question is: could this stereo amp be bridged into a monoblock? If so, how? But I think it is already bridged, right?
Thanks in advance.
 
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After a few days of listening one thing is sure: this amp plays well above his price range.
Even this short burn-in time caused a further development of the sound, it's even more refined, clear, relaxed.
The handling of the bass is unbelievable.
This amp doesn't want to attract attention - it's just there without screaming "here I am, master of the universe", it's just plays music. But... correction... it attracts attention with his speed, it's unbelievable fast.
Time goes by, hours after hours, CD after CD (with many of them I think I've never heard it) and I just don't want to stop listening.
I'm deeply impressed.
 
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Hi Viet,
a friend of mine has Magnepans (4 ohms) and would be interested in this amp (it means I should build it...), but he thinks he (or the Maggies) need more power, because they are very hungry. So the question is: could this stereo amp be bridged into a monoblock? If so, how? But I think it is already bridged, right?
Thanks in advance.
Hi Viet,
any idea?
 
Looks fantastic, I was not expecting that! I typically use silicone 12awg/4.0mm2 wire in my amps, never thought about using some furutech I may have to try it. I use Furtech FS-a36 speaker cable on my main system, and all my interconnects are FA-aS22, I love their cables. I tried to follow your wiring but got lost in the twists, where are the VU meters getting signal from? What's the grounding jack on the back connecting to internally? I would have assumed the main grounding bolt but it looks like you terminated it elsewhere.

I've been often debated whether or not I should give it a go using Front Panel Express (a Schaffner company in Seattle) and I think you might have just convinced me.
@bloqhed , You can't wrong with FPE. I've been using them years and IMO, they add the finishing professional look to a piece of DIY kit. It does add some extra expense to the project, but overall, it's a nice touch to any project. I always send in my own panels, and have never used their own material offerings.
 
Huhh... the listening test started with a scare, there was a distinct beep... fortunately I quickly determined that it was caused by the Korg B1 preamp, for whatever reason. Switched to the Iron Pumpkin, the amp is incredibly silent, wow, I hadn't experienced anything like that with any other amp.
The sound... although the amp is new and the whole system is cold, the first thing that strikes me is the incredible detailing. No, the amp is not analytical, it just represents everything that the recording contains. He doesn't add anything either, although I'm now hearing/discovering details that I was previously unaware of - especially with acoustic instruments.
The second thing I notice is the bass richness, very deep but at the same time very controlled and not bloated - it gives me goosebumps, which is a good sign. The amp is very fast, impulses, transients - as far as I can tell - are reproduced extremely quickly and accurately.
The mids are beautifully open and present without being overdone or fatiguing. Allan Taylor is standing in front of me, the vocals are clear and not lost in the music like I've sometimes experienced.
The highs are crystal clear and become clearer with increasing playing time (= temperature), age, etc. of the amp. They are very nicely defined, great. Not a trace of exaggeration, overemphasis, they are never tiring or harsh.
The stage is wide, deep and high, I'm thrilled.
The overall sound character is on the more neutral or natural side, the amp does not offer warmth or sugar sweetness, but does not lack them at all. If you still need warmth, you should operate the amp with the tube preamp :) (kit available soon :D). I was able to listen to a top-of-the-line system on Tuesday with friends (with Spectral monos for 65,000 dollars with M.I.T. cable for 45,000, Wilson Audio... and so on) and the behavior of the amp reminds me a little of what I heard there, as far as the neutral and incredibly pleasant music-making is concerned.
Comparison with Class A? Tedious, it's more a matter of taste. I like Class A, but when listening to this Class D amp I don't miss anything. And that speaks for this amp.
Overall - great! I'm going to try different preamps and speakers now - if that's not fun!
Thank you X!

Here a picture with my self-developed open baffle :)

View attachment 1164717
IMO, the ability to reproduce acoustic instruments well, is the true test of a great sounding amp - if not the entire system. And, you've just found out how well this Class D performs. This amp adds the HD to audio, like 4K did for TVs. :)
 
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Hi Viet,
any idea?
Yes, the Warp-1 works well with Magnepans. Several customers have tried. The amp in BTL mode can handle 4ohm loads. You can monoblock a Warp-1 by changing some jumpers (0 ohm resistors) and dip switches for parallel BTL or PBTL. But this achieves 2ohm capability and power derived from higher current and not peak voltage increase. Which model of Magnepan is your friend using?
 
Founder of XSA-Labs
Joined 2012
Paid Member
Hi Viet,
any idea?
Yes, the Warp-1 works well with Magnepans. Several customers have tried. The amp in BTL mode can handle 4ohm loads. You can monoblock a Warp-1 by changing some jumpers (0 ohm resistors) and dip switches for parallel BTL or PBTL. But this achieves 2ohm capability and power derived from higher current and not peak voltage increase. Which model of Magnepan is your friend using?

The LRS is rated 85dB but behaves like an 80dB at 2.83v speaker and has 3.3ohm impedance. I use Warp on 82dB speakers (FAST TL) and it’s fine. I think it will work.
 
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Just one last question:)
The board connectors arrived, so I can mount the amp error LEDs.
I can't see on your pictures: are resistors required for the LEDs or are they contacted directly? What's the voltage of the error connectors - I'm using 3 mm LEDs and I think yours are 5 mm, so the could be a difference.