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Has anyone used this TPA3251 amplifier?

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NickRPT

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I also have the tpa3255 with the bluetooth few months now and i already have my first problem ! Right channel make funny noises after play with the volume and i think is the potentiometer . So you get Chinese amps with the micro potentiometers and you have very bad imbalance on the low volumes , you get Chinese amps with big proper potentiometers without imbalance but they don't last :)
Anyone else with same experience?
 

Xulonn

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Interesting, I would probably have tried using a PC 2.1 system with a powerbank for that "bass" instead.
Perhaps at home, but not for the micro stereo system that I bring every week to the market and set up on the outdoor terrace railing behind my 4' artisans table every week for four hours. I'll post pics when I get everything and use it at the market.
 

Paulmac

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This is all interesting to me. Ive just ordered the AIYIMA 04 with the TI TPA3251 chip. I found it on ebay because I was looking through the Texas Instruments website, trying to find the most recently introduced TI class D with what TI promotes as its Ultra-HD with pure path circuit design. I have had an SMSL AD18 I used for about a year and a half. The SMSL impressed my brother who is a musician (went to the Sydney Conservatorium of Music etc) who concentrates on electric guitar these days. He came over and plugged his guitar into the SMSL and was amazed at the sound, especially the speed of the amp. Zero delay between the time he plucked a string to when it cam out of the speakers. Apparently that's very rare. "It sounds like we are in a studio" He said. Then he asked how much the amp cost and I told him. And he took the Lord's name in vain and said "What the hell? Do you know how much people pay for equipment that can do that ?" I said, being a VW nut, not a musician, "no idea". And he said "Thousands." I said well you cant have heard many modern Class D designs Dave and he said, oh its class D? I said yea, and he said, well mostly young whipper snappers buy those. And so seeing as its his birthday and seeing as he's on the bone of his arse right now, I figured I'd try the Aiyima and send him which ever is worse sounding out for the two for his birthday. Making music involves, it seems, a whole raft of considerations and aims which are different, very different, to the aspirations of people who seriously enjoy listening to music. One thing came out of the measurements (was it in this forum or some other?) of the SMSL AD18 was the nature and extent of the amp's distortion. And that, for the musician who was blown away by the amp, not a consideration to his ears and perception. The thing that astounded him was the timing of the amp. It was fast. He's no slouch and it kept time with him. And it sounded live. Because it, well, was. Normally its a very nice amp for money. When you plugged a guitar into it, it sounded like a thousand bucks worth. Not its purpose in life, but it did sound way bigger than it is. Im hoping the Aiyima in its own way will be as good.
 
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Westsounds

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Interesting reading about class D amplifiers I think they are starting to become more and more mainstream genuine alternatives now, in live music reproduction they are a bit of a no brainier as they can be much smaller than solid-state and valve yet provide massive power in comparison and are also much more affordable generally. I play guitar, and guitars, particularly electric guitars, are low-fi instruments (reproducing acoustic guitars authentically is something completely different). The thing that gets most guitarists going is the characteristics of the amplifier generally or tonality, this tone is what gets most guitar enthusiasts excited. More and more new guitar amps use class D as its driver now, as the quality is not that important, but class D these days even seem to have that in spades, its such a good way to amplifier audio.
 

Toku

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I've heard that the new tpa3255 without the bluetooth , got very bad pop on and pop off sound ! People that have try it can they share ?
Is your question about this amp?

https://ja.aliexpress.com/item/4000...b0d-5d29b7d8c-2d2c7d2c7d2c7b2d7c1d8b5d2c7d5c2 8587-412a-9bb0-0035c4f2e24d&ws_ab_test=searchweb0_0,searchweb201602_6,searchweb201603_53

I bought this product and tested it.
The pop noise associated with turning the power switch on and off is the worst of the amps I have tested so far. In some cases, it damages the speaker.
I wrote this in a product review, but you should never buy.
As far as the PC board is concerned, it is the same circuit as the amplifier of TPA3251, and I think that it is a product in which only the amplifier chip is replaced with TPA3255.

The TPA32xx series has a built-in pop noise prevention function, but I think it is because the setting constant of the pop circuit was not changed when the chip was changed from TPA3251 to TPA3255.
 

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Toku

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Back panel and inside the Aiyima amplifier...simple, basic, and no unwanted features or complexity!

View attachment 52449

View attachment 52450
I purchased and used two of this amplifier.
It is one of the excellent TPA32xx amplifier products.
There is no pop noise.
It has a high damping factor among Class D amplifiers and has excellent woofer braking capability.

However, according to the information on the net, there are several versions of this product, and it seems that the behavior is different for each.
The product I purchased is an early version and the brand name is TILEAR instead of AIYIMA.
 

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Westsounds

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Is your question about this amp?

https://ja.aliexpress.com/item/4000...b0d-5d29b7d8c-2d2c7d2c7d2c7b2d7c1d8b5d2c7d5c2 8587-412a-9bb0-0035c4f2e24d&ws_ab_test=searchweb0_0,searchweb201602_6,searchweb201603_53

I bought this product and tested it.
The pop noise associated with turning the power switch on and off is the worst of the amps I have tested so far. In some cases, it damages the speaker.
I wrote this in a product review, but you should never buy.
As far as the PC board is concerned, it is the same circuit as the amplifier of TPA3251, and I think that it is a product in which only the amplifier chip is replaced with TPA3255.

The TPA32xx series has a built-in pop noise prevention function, but I think it is because the setting constant of the pop circuit was not changed when the chip was changed from TPA3251 to TPA3255.
Wow, thank you for this. This is just the sort of information I need. I was just about the pull the trigger on one of these amplifiers last night and thought I would do it in the morning :) Still had the browser open to it this morning.

The pop noise would annoy me and as you say could even damage speakers, its such a shame really as it seems the TPA is where the value for money / quality action is. It's just knowing which one to get, if only I knew of a solid one with minimal hiss and no nasty pop noises. Had a play with the Fosi TDA7498E again last night, its ok, Im wondering if it would transform a bit more after some burn in but I doubt it. There is no pop bump on power on though, but there is a very slight bit of low level hiss if you put your ear near the speaker, but not too distracting. Still it is very good value for money with regards for what you get for your money especially when you consider solid state amps and prices. I just think there may be better bang for buck out there with sound quality / money.

Im sure the Allo Volt + D would be great also that someone suggested to me. But its really quite a bit more money and then theres less power, who wants less power :)
 

KR500

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I checked at Mouser.com for the 2604 opamp and it is no longer available , then saw a note that it will not work with over 20 volts
 

lashto

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.... I will use it in a "portable" stereo system, and I feed it with line-level output from a Cayin N3 portable DAP. Every Tuesday morning on a covered terrace at the local food/arts/crafts market, as I have been doing for six years, I play international "happy music" at my vendors table. Since I dropped my old Trends TA10.1 T-amp and broke the volume control shaft, I have been using my backup mini-amp, an el cheapo Lepai 2020 T-amp with a 12v SLA battery as a power supply. Loudspeakers are a pair of 25 year old Yamaha NS-A325 tiny mini-monitors. Although severely bass-limited (150Hz), people marvel at the quality of the sound and many ask about my speakers.

But I want to improve things a bit - especially by adding a bit of bass without resorting to using a small subwoofer. And that means bigger speakers and a more powerful amplifier. So for future "portable" duty, as soon as everything arrives, I will use the TalentCell power bank to supply 24vdc (29v dropping to 21v as the battery depletes) to the Aiyima amp. The speakers will be my new Q-Acoustics 3010's. Source will remain my Cayin N3 DAP.

Perhaps in the future I will get a UMIK-1 microphone and do a coarse measurement of the sound with the various amps, speakers and power supplies.

More fun for an old audiophile!

The new system should bring a serious improvement to your hobby market(ing) :)

And btw, in case ease of use/transport is the main criteria, why not going with a Bluetooth speaker!? Way less components/cables/etc to carry & install.
E.g. the Minirig 360degrees sound could be perfect for outdoor market conditions. Below you have a good quality sound demo using binaural mics
... many other similar sound demo&comparison videos on that channel see https://www.youtube.com/user/clavinetjunkie/search?query=minirig
 
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Toku

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Are you satisfied with the volume control potentiometer? After all, it is clearly not of the best quality...
I am not happy with the volume pot of most amplifier products and HPA products, not just this amplifier.
It's not about the quality of the volume POT, but about the misselection of the volume POT.
For the volume POT for adjusting the volume of audio equipment, the one with the characteristics of taper A has been used for a long time. However, most of the Chinese products use the taper B volume POT. As a result, a violent gang error occurs and the volume changes rapidly with the rotation angle of the knob.

I said this in a review of ASR's SMSL SP200, but I was very disappointed that many audiophiles didn't seem to understand the difference between Taper A and Taper B.
Of course I also asked SMSL to make improvements directly, but they didn't understand.
It's a pity that ASR amirm hasn't said anything about this so far.
So I'm very dissatisfied with the volume.
 

conuss

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It's not about the quality of the volume POT, but about the misselection of the volume POT.
So, at a comfortable volume level, you are satisfied with the quality of the potentiometer?
 

Toku

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So, at a comfortable volume level, you are satisfied with the quality of the potentiometer?
There are certainly differences in sound depending on the type of volume pot, but that is a small difference for me. But audiophiles will see that as a big difference. I'm not an audiophile. I used to be an engineer who used to design audio equipment for TV broadcasting stations at a large Japanese company. Therefore, I always pay attention to the stable operation of the device rather than the difference in sound. Therefore, I have no special complaints about the sound quality of the volume pot of the Chinese TPA325* amplifier. Above all, the price is cheap.

I find it difficult to adopt a high-priced volume POT for inexpensive Chinese audio equipment.
However, if the product price is over $200, I would like to use a volume pot of the class below. I think audiophiles will be satisfied with the sound quality if this class volume POT is used. Of course, it is necessary to select taper A.

http://www.tkd-corp.com/products/pot/potentiometer.html#cp600
 

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gasolin75

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Does the Aiyima A04 amplifier have any channel imbalance at low volume and what about pop noise when you turn the amp on and off ?
 

Toku

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Does the Aiyima A04 amplifier have any channel imbalance at low volume and what about pop noise when you turn the amp on and off ?
Aiyima A04 does not generate pop noise at power ON/OFF. Built-in pop noise prevention circuit.
Disturbance of volume balance between channels occurs near the minimum volume value, but there are variations depending on the product.
Chinese products (including Topping and SMSL) use Taper B in the volume pot, so it is unavoidable that the volume balance is slightly disturbed.
 

gasolin75

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Than i just use my Fosi TDA7498E amp (2 second version, uses black screws at the back you use hex key for, the first version is with black philips head screws) it has no channel imbalance and no pop noise at all, what it does have is a weak static noise or a dirty potmeter, i don't hear it every time i use the volume knob and when i hear it, it's weak.

It comes with a 24v 4.5a power adapter where fosi audio recommends not to use a 32 volt power adapter but one that is 24 volt and 10a, so i have ordered one.
 
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D

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One thing you haven't noticed is electromagnetic radiation from pulse width modulation of class D amps and dirty electricity from switch mode power supply.

My chinese TPA3251 amplifier emits electromagnetic radiation at 570khz which a portable AM radio picks up. I read TPA3251 specification PDF, and I discovered that pulse width modulation frequencies of TPA3251 are between 575khz and 600khz. So, your body is attacked at pulse width modulation frequencies when you are near a class D amp. Hint // Living near an AM/FM radio station is bad for your long-term health.

Dirty electricity in house wires is converted to electromagnetic radiation in various low frequencies including AM radio frequencies. You can use a portable AM radio to cheaply figure out whether there is dirty electricity problem in your house.

Dirty electricity from switch mode power supply can be reduced through common mode choke and other tricks, but you need to attach such devices to SMPS or buy a high-quality switch mode power supply that has dirty electricity suppression components.

So, a linear power supply can give you a peace of mind. Class AB amps do not use pulse width modulation. I'm looking into class AB amps with linear power supplies. Dayton APA150 seems to be an affordable class AB amp with a linear power supply. All electronics emit some amount of electromagnetic radiation, but pulse width modulation is certainly an offender. Some people can feel the difference between class D and class AB with their bodies.
 
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somebodyelse

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You could use a cheap TV dongle and some free software to get a much more quantitative assessment of the radio frequency levels in your house - search for RTL-SDR for details. Compatible dongles start at ~$15. This will let you put the different levels of RF at different frequencies, and at different distances from things, into perspective.
 

LiloLee

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Living near an AM/FM radio station is bad for your long-term health
Don't we all live in areas of AM/FM radiation, since that is how radios/tuners pick up their signal? How much worse is the tda3251 compared to what is already being transmitted?
 
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Don't we all live in areas of AM/FM radiation, since that is how radios/tuners pick up their signal? How much worse is the tda3251 compared to what is already being transmitted?

I pick up signals from several hundreds of kilometers away. But, that signal is weak. If you are not within several kilometers of a radio station, radio signals can be blocked by walls.

Next to me, TDA3251's signal is as strong as some AM radio frequencies in my house. I'm trying to minimize exposure across all frequencies. That means no wireless technology in my room. I'm probably going to put RF-blocking fabric on my room's windows in order to prevent radio signals and cellular signals from coming in.
 
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