• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

My experiences with chinese generic TPA3251 and TPA3255 amplifiers

Joined
Jan 10, 2020
Messages
45
Likes
15
#23
I'm still looking around for one of the best small off the shelf class D's with the aim of finding the best sound per value. Never tried TPAs but they seem to have the same issues as most do. Anyone have any other ideas of whats out there that is 'the one to own'?

I just tried another from Amazon as I could try on a return basis, its a TDA98e, its the first 98e I tried, and it was selling quite a bit cheaper than the SMSL 98e but still having great reviews. I haven't given it much time but from the start my verdict was the amplifier isn't bad but lacks a lot in midrange body and solid drive. Detail is quite nice though and nice and delicate sounding just a bit soft and lacking a bit of presence in its delivery. Hiss is slightly there but again not terrible. Its only really audible if you turn the amplifier quite loud when there is nothing playing, but most amplifiers would have some audible noise if you did that, but it claims to have nothing in the ad. Thankfully there is no pop or bump when you turn it on though. There is quite a bit of scratchiness on the volume pot though but things with these size volume pot are a bit prone to being not very good I expect, and the quality control would be low on these I imagine. But overall with everything considered its enough to make me want to try another.

This was the amp

https://www.amazon.co.uk/gp/product/B077GWVHHN/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

My next step is maybe order direct from China, again its a risk but its almost half the cost again, the return thing will be out of the question but maybe I'll get lucky and get a decent amp. I was thinking of trying one of those TPA's which seems to be the most modern. Or is there better? Hopefully I will be more enthusiastic about the TPA than the TDA
 

somebodyelse

Major Contributor
Joined
Dec 5, 2018
Messages
1,100
Likes
707
#24
They may have the same sort of issues with cost cutting and poor implementation in the cheap ones, but even a badly implemented TPA3255 like the generic one QuantAsylum tested performed better than the datasheet (best case) performance of the TDA7498E.
 

Lorenzo74

Active Member
Joined
Nov 17, 2019
Messages
104
Likes
55
Location
Italy, Rome
#25
They may have the same sort of issues with cost cutting and poor implementation in the cheap ones, but even a badly implemented TPA3255 like the generic one QuantAsylum tested performed better than the datasheet (best case) performance of the TDA7498E.
I agree. i have tpa3255 tested by QuantAsylum.
with adecent power supply 48V DC 800W i found no issue at all.

i also have smsl 160 (7498) differences are evident especially if you have Umik1.

now it seems tpa is flourishing in many low cost products:
https://it.aliexpress.com/item/4000...E5fQpue3IPYKrZigYbxoCaZEQAvD_BwE&gclsrc=aw.ds

find a better ratio Watt (0.1%distortion)/Dollar...
to have better performance you have to go to icepower, Pascal,Hypex,Purifi but cost per dollar is much higher...
 
Joined
Jan 10, 2020
Messages
45
Likes
15
#26
They may have the same sort of issues with cost cutting and poor implementation in the cheap ones, but even a badly implemented TPA3255 like the generic one QuantAsylum tested performed better than the datasheet (best case) performance of the TDA7498E.
Yes the TPA do seem to be favourable with many. I would like to try one. I also find the Allo Volt + D an attractive package which may translate into very good sound quality with its better components. The trouble is they cost a considerable amount more than the rest of the cheaper ones which also have more power, the Volt will only be around 30 watts 8 ohms pc, I'd rather have more power.

I agree. i have tpa3255 tested by QuantAsylum.
with adecent power supply 48V DC 800W i found no issue at all.

i also have smsl 160 (7498) differences are evident especially if you have Umik1.

now it seems tpa is flourishing in many low cost products:
https://it.aliexpress.com/item/4000...E5fQpue3IPYKrZigYbxoCaZEQAvD_BwE&gclsrc=aw.ds

find a better ratio Watt (0.1%distortion)/Dollar...
to have better performance you have to go to icepower, Pascal,Hypex,Purifi but cost per dollar is much higher...
Great points here. And yes these little amps do offer great watt per dollar. I am really looking for the sweet spot where the SQ is excellent yet still affordable (or cheap even). Thats the aim to get the best in the cheapest package yet something that performs well. And these class D's do seem to be in a class of their own when it comes to that.

Thats a nice little amp in the link there. 300wpc is that right? into 4 ohm though, I will check the specs on that. I didnt think 3255's were that much. A nice package with the power supply on board as well.
 
Joined
Sep 19, 2018
Messages
80
Likes
10
#30
Very nice. So that is the daddy of class D power/price/performance at the moment then. I was just about to order when I see the 3255 is unavailable to order only the 3250 can be bought. Just as well wait for the higher power unit, it is double the power.
Only wattage difference?
 
Joined
Jan 10, 2020
Messages
45
Likes
15
#31
I'm not sure.

I guess you could say why bother if its the same. I just prefer more power if its exactly the same. With more demanding speakers the extra wattage usually translates into more grip, control and volume if you want it. And to get realistic or more demanding levels its always a good thing.
 

sychan

Member
Forum Donor
Joined
Aug 24, 2019
Messages
41
Likes
17
#32
I'm not sure.

I guess you could say why bother if its the same. I just prefer more power if its exactly the same. With more demanding speakers the extra wattage usually translates into more grip, control and volume if you want it. And to get realistic or more demanding levels its always a good thing.
When I was looking at the specs for the 3251 vs 3255, the 3255 obviously had more power, but also seemed to have more distortion at mid to high frequencies at comparable output. This is the graph for the 3255 that shows how THD+N rises as the frequency goes up, peaking at .1% at for 25W:
1591830347309.png

Here's the same graph for the TPA3251, where you see that you don't get to .1% until 75W (basically full power for the 3251):
1591830510848.png


So the extra power doesn't come for free - you get more distortion/noise at the higher frequencies at comparable power levels. But I guess the question is, would you hear it, and does it matter to you?
 
Joined
Jul 2, 2020
Messages
10
Likes
0
#33
I bought this and paid for expedited shipping. It arrived today. However I cannot get any sound output(either bluetooth or aux).

Has anyone received this amp yet? I do notice some shorted solder on the back of the board behind the amp chip. Would that be a problem?
20200702_121259.jpg
 

somebodyelse

Major Contributor
Joined
Dec 5, 2018
Messages
1,100
Likes
707
#34
What amp is it exactly? There are several designs around with TPA325x and bluetooth. It doesn't look like that solder is a problem to me - that whole area is connected anyway. It looks like an attempt to improve the heat flow from the chip into the ground plane and towards the heatsink mounting screws.
 
Joined
Jul 2, 2020
Messages
10
Likes
0
#35
What amp is it exactly? There are several designs around with TPA325x and bluetooth. It doesn't look like that solder is a problem to me - that whole area is connected anyway. It looks like an attempt to improve the heat flow from the chip into the ground plane and towards the heatsink mounting screws.
OK, that's good to know. It is the 3e DAP1002 http://www.3e-audio.com/finished-amp/tpa32xx-all-in-one-amplifier/
The amp powers up fine, bluetooth connects fine, the LEDs around the volume knob seem to be working fine but there is absolutely no audio out to the speaker terminals. Not even a hiss. I have tried with volume knob at the max and at the min and in between
 

somebodyelse

Major Contributor
Joined
Dec 5, 2018
Messages
1,100
Likes
707
#36
OK, that's good to know. It is the 3e DAP1002 http://www.3e-audio.com/finished-amp/tpa32xx-all-in-one-amplifier/
The amp powers up fine, bluetooth connects fine, the LEDs around the volume knob seem to be working fine but there is absolutely no audio out to the speaker terminals. Not even a hiss. I have tried with volume knob at the max and at the min and in between
Ah...the first I've heard of that's got their hands on one. Does it come with any documentation? The product page is lacking the data sheets, dsp profiles etc. that we see for their other products. You could try asking @3eaudio - I hope it's one of those "why didn't I think of that?" moments!
 
Joined
Jul 2, 2020
Messages
10
Likes
0
#37
Thanks, I found their account on here and reached out. No documentation of any kind, not even a power cord(though I have extras, so not something I'm complaining about. It came well packed and in about 2 weeks with the DHL upgrade.
20200702_153150.jpg
20200702_153222.jpg
 

Toku

Addicted to Fun and Learning
Joined
Apr 4, 2018
Messages
744
Likes
547
Location
Japan
#38
Thanks, I found their account on here and reached out. No documentation of any kind, not even a power cord(though I have extras, so not something I'm complaining about. It came well packed and in about 2 weeks with the DHL upgrade. View attachment 71682 View attachment 71683
The product package does not include the AC cable. Only the WiFi antenna and rubber feet are included.
 
Joined
May 16, 2020
Messages
44
Likes
52
#40
How does the amp sound to you and what were you using previously? What speakers are you using it with?
I received mine from 3e-Audio some weeks ago now and it sounds very good. I think this is an excellent implementation using good quality components. The Bluetooth works well (Apple AAC and APTX) but of course this is still lossy as it doesn’t support the HD Codecs. The sound from the RCA inputs is best.

I use it to drive a pair of small KEF UniQ speakers and it sounds really good. So far for me this is one of the best small digital amplifiers currently available and I have tested quite a few !! It is also the most convenient with its build in Power Supply.

If I have one issue it is the fact that it automatically goes into standby after about 30 minutes of no input. So the amp keeps turning off - usually I leave my amps on 24/7. Hopefully this can be fixed once 3e-Audio release the necessary details to re-program the DSP chip but this is probably not something that most users will want to attemp.
 
Top Bottom