Class D amplifier with TPA 3250 board


Hello,

I'm new to this forum. I recently purchased my endgame setup comprised of Closer Acoustics Ogy speakers (91 SPL), REL T5X subwoofer and a custom hand built tube amplifier with EL34 tubes. The tube amplifier is giving me trouble with hissing noises, so it's constantly at the artisan's workshop. Since my speakers are extremely efficient, I was wondering about smaller amplifiers as an escape route (if the artisan can't fix the amp, he surely can). The Octavio Amp looks nice on paper. So does the Atoll IN80. Is one obviously better than the other for my revealing speakers?

Folks on another forum I shall not name seem to heavily imply that all amplifiers should sound the same (or very similar). They rave about these cheap tiny Topping/Aiyima amplifiers with class D TPA 3250 amplifier boards. These same boards are used in Genelec active monitors, so they must be good? I'm flustered because there no direct comparisons between these TPA 32xx amplifiers and more conventional/expensive branded amplifiers. The same folks on the forum I shall not name imply that I'm a dunce for spending so much money on a tube amplifier (quote: it's a distortion factory and it can't play grindcore metal music so it sucks). If it weren't for the hiss I wouldn't post here. 

Can I cheap class D amp replace a custom hand-wired EL34 tube amplifier for extremely revealing Closer Acoustics Ogy speakers?

128x128kokakolia

Glad to read/hear it, and...

I told you so (regarding the sub;-).

 

DeKay

As far at the argument that an amp was tested and it was 10 percent distortion???

@timlub That came from the specs published by the manufacturer of the chips:

TA2024 10% at full power (10W)

TA2020 10% at full power (13W)

TA2022 10% at full power (125W)

Tk2050 10% at full power (117W)

TAS5613 10% at full power (150W)

TAS5630 10% at full power (160W 8Ohms)

...and so on; in fact I've yet to see any class D chip that did not spec 10% at full power.

Typically they are operated at considerably less than full power, but if you are looking at specs and power is one of those things in which you're interested, its a good idea to look closely to see what the claim actually is. In the case of the raw chips this isn't such a big deal since a designer has to implement the design and will spec the resulting amplifier when that's done.

But I've noticed a lot of the Chinese offerings tend to state the '10% full power spec' when the power supply accompanying the amp won't support it- if you don't watch it, you'll think you're buying a more powerful amp and one of a lot less distortion. IMO its a bit misleading.

@atmasphere Looking at those specs the TA2024 looks like junk haha. Who on Earth wants just 10W at 10% distortion LOL?

@dekay It looks like I have been pissing off the neighbors this past week. I'm still rocking that puny little Sure amp. It's really cheap junk amp. The volume knob spins around freely and the volume adjustment doesn't seem to do much. But I couldn't care less because it sounds so good! And the Bluesound Node has basic volume adjustment from the phone. 

Oh yeah, the tube amplifier is still at the workshop. The poor artisan is struggling to tame down the noise floor. I kinda forgot about him. I'm having too much fun. 

I never thought that my audio journey would end with a 40€ amp the size of a matchbox... Everything about it screams "cheap junk". It's like the Toyota Echo of amplifiers. 

 

As long as you don't push them too hard, it can be a bit surprising how good many of these little amps can actually sound. Of course then you start to wonder how good it can get... In our own work on class D amps (we have a design entirely our own) I've come to the conclusion that power amps based on tubes are on life support.

@kokakolia I was in Italy on vacation and somehow was unable to answer any post here on Audiogon from my phone (which is actually very annoying, I can only do it on my laptop)

I'm glad, and not really surprised, that you like your new class D cheapie. I have a feeling a lot of the "bad" rep comes from people who have never actually took the time to really try one in their system, or just took the cheapest crap they could find (like a Lepai) connected it to some garage speakers through lamp cord and are judging the whole bunch based on that.

 

My system is far from perfect but I never ever had someone telling me "you are using cheap class D amps, aren't you?" based on listening only. They usually say it sounds good then raise their eyebrows when they see the tiny amps on their shelf.

 

Enjoy your new toy!

@rolox Thanks. I have to stress that the class D cheapie doesn't impress without a sub! This amp is all about the mids and highs. It's hard for me to recommend the Sure amp in absolute terms. You get 0 versatility. No bass. Only 10W of power. And the volume knob sucks. The Bluesound Node makes this thing usable. 

The Sure amp just happens to sound great with the OGY. I think I lucked out. 

OP,

 

Great. Glad to hear it. Enjoy the music and relax. Sounds like you had a stressful journey.

@kokakolia yeah but you chose to get the cheapest of the bunch, which is fine, but you might have gotten a better volume pot AND more bass (to be honest I'm surprised about the lack of bass, but of course in the end 10 watts is just 10 watts) with a Trends or an Amptastic ;) 

 

As long as you're happy it's all that matters. Enjoy :)

 

@rolox The Amptastic vanished from existence. This amp was my first choice, the price was very reasonable at around 100€. And the design was perfect.

The Trends was 200€ and with the same on paper specs as the Sure. I read a review somewhere comparing the Trends with the Sure and the conclusion was that differences were negligible.

Granted, the Sure amp is a bit of a false bargain because the price hikes to 80€ with external power supply + shipping.

On a side note I’m shocked how much the REL T5x improves the sound. It makes me wonder how the far cheaper but still delightful Q Acoustics 2020 sounds like with the REL.

Do I really need such bespoke speakers (OGY) if I have a REL?

Answering that question would require spending more money and time. So I won't bother to find out. 

I have built several Class D amplifiers.  I used a TPA3255 by 3e audio.  I switched out a few key caps on the board. I used a 12 amp switching supply and added 120,000 mfd for the supply.  I engaged the PFFB circuit which makes the frequency response stable at all impedance loads, I wired it for balanced operation.  

Hello, new here. Been looking at the 3E Audio 3255 PCB for my next build. Did you find it an improvement over the Aiyima A07 TPA-3255 based unit soundwise?

 

Thanks much.