TPA3251/55 High Power Class D Amplifiers

Studio19atx · « **Reply #80 on:** 12 Jul 2018, 04:34 pm »

Just as a curiosity, I wonder how do 3255 sound in comparison with the Hypex modules (NC252P). From my experience the hypex smps play a big role in the sound of their amps. I have tried NC500 with other non Hypex SMPS and there is a noticeable difference in sound.

gregfisk · « **Reply #81 on:** 12 Jul 2018, 05:03 pm »

David, could you point me to the FX audio 3255 amp? I only see the FX amp using the TPA 3250.

Thanks,

Greg

WC · « **Reply #82 on:** 12 Jul 2018, 06:23 pm »

Here is the Amp Board as a 2 channel unit

davidldl · « **Reply #83 on:** 13 Jul 2018, 12:51 am »

>David, could you point me to the FX audio 3255 amp? I only see the FX amp using the TPA 3250.

>Thanks,

>Greg

Sorry Greg, I was talking about two different chips. I did not state this in my comparison. For FXAudio, I only saw the TPA3250 model. I'm unaware of any FXAudio TPA3255 amps.

David

davidldl · « **Reply #84 on:** 16 Jul 2018, 04:54 pm »

The YJhifi Audio amp is very strange. I don't know if it has a design flaw or I just got a bad unit.
If I turn it on without it paired with my cell phone it would make continual popping sounds when it tries to lock in on either blue tooth or the line input.

If it is paired and then turned on it will pop once and lock and the blue indicator light would come one, then I can unpair it and use the line input.

If anyone has this amp please let me know if yours behaves the same way or not. If this is in the design, this amp should probably be avoided unless you are definitely only using blue tooth.

David

wushuliu · « **Reply #85 on:** 16 Jul 2018, 05:20 pm »

I would avoid any cheap chinese amp with blue tooth unless that's the feature you need or sound quality is secondary. The more chips/features are added the more noise there will be to the system and any software programming involved will likely be subpar.

davidldl · « **Reply #86 on:** 17 Jul 2018, 10:27 am »

It is behaving better now, I had 'ended my connection', It looks like I just had to 'Forget' the bluetooth connection on my phone.

David

ljbrandt · « **Reply #87 on:** 1 Apr 2019, 05:03 pm »

What you do think of this board from ALI-E?
https://www.amazon.com/DC50V-TPA3255-Class-Digital-Amplifier/dp/B0776NFRRB

Looks pretty plug and play for even the non-DIYer.

davidldl · « **Reply #88 on:** 3 Apr 2019, 12:17 am »

Quote from: ljbrandt on 1 Apr 2019, 05:03 pm

What you do think of this board from ALI-E?
https://www.amazon.com/DC50V-TPA3255-Class-Digital-Amplifier/dp/B0776NFRRB

Looks pretty plug and play for even the non-DIYer.

They look easy to put together but just be aware that those binding posts seem to stick out pretty far on the underside of the board.
It might make it a bit harder to mount in a box.

--David L.

will mac · « **Reply #89 on:** 15 Apr 2019, 09:06 am »

Are there any ti modules with plug in op amps?

TJude92 · « **Reply #90 on:** 20 Apr 2019, 06:32 pm »

I'm looking for an amp to drive a pair of Dahlquist DQ-10's which require 250w each @8 ohm. Been using a Hafler-500 for years but want to go class-D. Definitely want THD that's comparable to the hafler, and looks like the 3255 can be used to do this. However, I can't find a dual-channel @250 into 8. Any guidance?

THanks!

rhing · « **Reply #91 on:** 7 Mar 2020, 02:42 pm »

A few weeks ago, I wanted to purchase the Aiyima TPA3255 2.0 amp through eBay, but the seller in China could not ship the amp due to the COVID-19 virus outbreak. They were great about it and refunded my payment, that left me with the only option to purchase the Aiyima TPA3251 2.0 amp through Amazon.com who had some inventory of these amps in the US.

I connected this amp to my main system using my Audio Research LS7 tube line stage preamp and modified Klipsch Forte II speakers. This is where I started my critical music listening and discovered that the right and left channels are reversed, so I switched my right and left hand RCA interconnect connections. My reference power amplifiers are a rebuilt McIntosh MC240 vacuum tube amp and Pass DIY Sony VFET Class A solid state amp I built with the diyAudio.com store kit offered several years ago.

Both of my reference amps are excellent and I am quite pleased with the low distortion, highly musical performances of both amps in my system. I connected the Aiyima amp to the Audio Research preamp and my speakers, and I have to say this little amp is impressive. First of all, it is very quiet with no music playing through it. I held my ear close to my high sensitivity Klipsch speakers and heard no noise. As for the sound, it is not as good as my reference amps, but it wasn’t that far off either, which is astounding considering that this amp is only $50 USD. The fact that the channels are reversed is my only real complaint about this amp.

I have my volume on the Audio Research set in the normal position I use for most listening, and I have the volume pot on the Aiyima amp set to 2 to 2:30 o’clock with best results at my usual listening level. I am very impressed with the frequency response from the lower registers to the treble. This amp has a smooth, neutral frequency response and tone. What is surprising is the separation and detail I hear with this little amp. The soundstage is large, but could have more depth. I am satisfied with my purchase even with the mislabeled channel connections.

I have placed an order for the OPA1622 op amps on DIP8 adapters, and I will try those. If I hear a significant improvement, I might be tempted to try the NJR MUSES02 op amps.

danali · « **Reply #92 on:** 7 Mar 2020, 03:08 pm »

did you have to add a power supply for the aiyima?

rhing · « **Reply #93 on:** 7 Mar 2020, 03:15 pm »

Yes. I wired up a Mean Well LRS-200-36 switching power supply and dialed the out to 30VDC to play it safe with the 35VDC-rated 3000uF Elna power filter caps inside the amp (two larger caps sitting next to the TPA3251 heat sink. I will put it into a nice Aluminum case with an IEC inlet and switch soon. Right now, it is mounted a piece of plywood.

maty · « **Reply #94 on:** 7 Mar 2020, 03:35 pm »

Rotated, optimized...

Aiyima TPA3251 2.0 HD325X Rev2.1, inside

Phloored · « **Reply #95 on:** 22 Apr 2020, 06:54 pm »

This looks intriguing. It's been 20 years since i have been into hi fi. I have lots old catching up to do.

lilolee · « **Reply #96 on:** 6 May 2020, 05:59 am »

Just bought the Aiyima TPA3251 from Aliexpress. Looking forward to trying it out.

8T_BoCO · « **Reply #97 on:** 16 May 2020, 01:36 pm »

My amazon-sourced Aiyima TPA3251 (US$ 50) arrived.

Out-of-the-box impressions are very positive. No harshness or distortion in any of the frequency range to my 50 y.o. ears.
Seller power supply spec is DC18-35V with DC32V 5A recommended, and I have a 32v-3A unit somewhere,
but a 24v 5A unit provided sufficient volume as a stand-in.

Nice case, but I had to use banana plug terminated speaker cable - no room to use my cables with spade lugs
due to RCA input proximity. So far, a C&C success.

The other amp of this type I've heard in this system is the (WINGONEER) TDA7498SE board with the 32V-3A PS.
It was the first high power chip amp to convince me of class D's ability to control a LF driver. Effortless volume
without triggering the fan, was my impression at the time. A little hiss in quiet passages, but for US$27, quite impressive.

system:
DAC > FX-Audio Tube preamp/buffer > ( this amp ) > 90 dB efficient 4 ohm acoustic suspension tower speakers

Bushellj · « **Reply #98 on:** 22 May 2020, 09:36 am »

Quote from: maty on 7 Mar 2020, 03:35 pm

Rotated, optimized...

Aiyima TPA3251 2.0 HD325X Rev2.1, inside

You have received the original Tilear version of this Aiyima TPA3251 Amplifier with the Black PCB which I believe are the better models. I also recently received one but it had the newer green PCB and some lower quality capacitors. I have upgraded the Op-Amps to the OPA1656 ones which seem to work well and actually sound very similar to the OPA1622 that I have also tried. I also use the Mean Well SMPS LRS-200-24 turned up to 30 volts !

davidldl · « **Reply #99 on:** 22 May 2020, 03:12 pm »

I see there is a TPA3255 amp (mono) that has a crossover that you can take out of the circuit with a switch. If anyone wanted to try out using two separate mono amps. It looks like Fosi Audio and Aiyima make one. They might be using the same boards. I'm not sure both come with power supplies or not.

https://www.amazon.com/Subwoofer-Audio-Full-Frequency-Switchable-Fosi/dp/B07VHG2LR9/ref=sr_1_1?dchild=1&keywords=Fosi+Audio+M03&qid=1590159801&s=electronics&sr=1-1

https://www.amazon.com/Subwoofer-Amplifier-Full-Frequency-Switchable-TPA3255D2/dp/B07VB3BRVF/ref=sr_1_2?dchild=1&keywords=300+Watt+Mini+Mono+Audio+Amp+Full-Frequency&qid=1590159309&s=electronics&sr=1-2

David