[fredgarvin]

I have a Breeze tpa-3116 that sounds nice in my computer setup. Better than the Dayton Tripath I had been using. However, with my Quartets in the main system it sounds pretty bad. I've read that the breeze has excessive gain and that could be the problem with the high efficiency speakers. The Panasonic xr sa50 from my home theater sounds much better than the Breeze.

Even though I doubt I'd find one of these boards that would rival my Coda amp I still have the urge to check out new boards. This one mentioned, the volt+ and the TDA-7498 boards such as the smsl sa-98E at 160X2 etc. all have good reports on beating the tpa-3116.

[wushuliu]

I have a Breeze tpa-3116 that sounds nice in my computer setup. Better than the Dayton Tripath I had been using. However, with my Quartets in the main system it sounds pretty bad. I've read that the breeze has excessive gain and that could be the problem with the high efficiency speakers. The Panasonic xr sa50 from my home theater sounds much better than the Breeze.

Even though I doubt I'd find one of these boards that would rival my Coda amp I still have the urge to check out new boards. This one mentioned, the volt+ and the TDA-7498 boards such as the smsl sa-98E at 160X2 etc. all have good reports on beating the tpa-3116.

If you don't need that much power the Volt+ sounds interesting with its capacitance multiplier feature. As for the Coda comparison, you never know, some people think these amps compete very well with high end. But my gut tells me  a proper beefy linear power supply might be needed to really go toe to toe with an amp like that.

[bavmike]

My Favourite TPA3251 based amp.

[wushuliu]

My Favourite TPA3251 based amp.

Icepower. But it's a specific model, right? Only certain ones have TPA chips.

Not sure how I feel about the SMPS being on the same board as the amp...

[bavmike]

It’s the 100AS. Icepower knows what they’re doing. The power supply on the same board isn’t an issue. All class D amps are going that way.

[fredgarvin]

If you don't need that much power the Volt+ sounds interesting with its capacitance multiplier feature. As for the Coda comparison, you never know, some people think these amps compete very well with high end. But my gut tells me  a proper beefy linear power supply might be needed to really go toe to toe with an amp like that.

I think you are correct about the power supply. The Volt+ is probably my next try, as you mentioned, I really don't need any more power than that. The Allo Volt has a stepped attenuator added and comes in around $100.

Not to derail Wushuliu, but have you checked out any of the Chinese class A offerings such as the 1969 Hood? With shipping they run about $200 and I have read some good reports.

[bavmike]

This guy makes very nice TPA3251 based amps in Germany. However very hard to compete with the engineering experience at Icepower.

http://www.360customs.de/2016/10/tpa3255-tpa3251-tpa3245-universal-one-for-all/

[wushuliu]

This guy makes very nice TPA3251 based amps in Germany. However very hard to compete with the engineering experience at Icepower.

http://www.360customs.de/2016/10/tpa3255-tpa3251-tpa3245-universal-one-for-all/

That guy is talented. He also thinks highly of the performance of the TI evm and the one i purchased, so I don't think I'm missing much compared to the ice power.

[Yaaaaaaaaaaaaaaa]

It’s the 100AS. Icepower knows what they’re doing. The power supply on the same board isn’t an issue. All class D amps are going that way.

I'm continually impressed by my Icepower 50ASX2-SE, and would like the opportunity to try an 100AS2, but I fear that they're not available to us mere DIY mortals...

[wushuliu]

I'm continually impressed by my Icepower 50ASX2-SE, and would like the opportunity to try an 100AS2, but I fear that they're not available to us mere DIY mortals...

Sounds like you got yours up and running (hope the move went well). How's it compare to the TPA?

[Yaaaaaaaaaaaaaaa]

Sounds like you got yours up and running (hope the move went well). How's it compare to the TPA?

We've still got both houses, so am spending varying amounts of time in both France and the UK...

I've set up my ICEpower with a buffer (http://www.ebay.co.uk/itm/Stereo-Tube-Preamp-Pre-amp-Board-Vacuum-Tube-Pre-Buffer-for-6N3-5670-6H3/291643694133?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649), driven by an RPi3 with Piano DAC in Dual Mono mode, running PicorePlayer - it is noticeably different to the TPA3250 and TPA3251 boards I have. I'm tempted to say better, with great definition, clear base etc, but I really need to do some refined comparisons using the same source.

On a practical side, having the power supply on board is a great benefit for packaging. For £17.50, the 50ASX2-SE is an absolute bargain and, I suspect, my 'go to' system...

[wushuliu]

We've still got both houses, so am spending varying amounts of time in both France and the UK...

I've set up my ICEpower with a buffer (http://www.ebay.co.uk/itm/Stereo-Tube-Preamp-Pre-amp-Board-Vacuum-Tube-Pre-Buffer-for-6N3-5670-6H3/291643694133?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649), driven by an RPi3 with Piano DAC in Dual Mono mode, running PicorePlayer - it is noticeably different to the TPA3250 and TPA3251 boards I have. I'm tempted to say better, with great definition, clear base etc, but I really need to do some refined comparisons using the same source.

On a practical side, having the power supply on board is a great benefit for packaging. For £17.50, the 50ASX2-SE is an absolute bargain and, I suspect, my 'go to' system...

Interesting. Thanks.

[rhing]

wushuliu,

I just picked up on this thread, so I thought I would chime in here about my latest experiences with the Texas Instruments TPA3255EVM Class D amplifier. I purchased this during the 50% off sale at TI, and then purchased a Mean Well LRS-350-48 switching power supply from Arrow for about $31.

The setup is rather crude in that I don’t even have an AC power switch in this setup. I added a pair of Altec Peerless 15335A 1:1 bridging transformers for converting single ended inputs into differential inputs. The wiring is Duelund DCA20GA oiled cotton-insulated Tin-plated Copper stranded wire, and the RCA input connectors are Neutrik chassis mounted connectors. Since I moved to Minnesota earlier this year and into an apartment, most of my electronics equipment is in storage including my drill press and wonderful Metcal soldering station. Everything is mounted on 1/4” thick Birch plywood sheets I picked up at Michaels.

Since my Klipsch Forte II floorstanding loudspeakers are too large for my living room, I searched a while for some bookshelf monitors that would give me the same lively presentation that my Klipsch speakers would give me. I found that in a pair of KEF LS50 speakers that I bought from a local dealer in Minnesota. Previously, I had my Wiener 2.0 TI TPA3118 PBTL (dual mono) amp and modified Astron RS-12A linear power supply working with the KEF’s and getting very pleasing results. However, once I switched to the more powerful TPA3255EVM amp, the KEF’s really opened up and the full, rich sound I’m getting out of these little monitors is astounding.

I am running the TPA3255EVM in stock form, but I intend to try out the PFFB (post filter feedback) mod, and possibly rig up a set of Wurth shielded inductors just to see how much I can eke out of this amp. If anyone tries the TI EVM out, I recommend that you allow at least 50 hours of play time before you really hear what sound quality this amp is capable of delivering.

My Forte II’s are in storage, and I have every intention of using them in my main rig once we move into a larger home. I am curious how they will sound with this more powerful TI Class D amp. I have a pair of bare TPA3251/3255 PCBs from drmord who regularly posts on the Class D forums on diyAudio.com. Once I have a complete lab setup again, I will build out drmord’s amps in PBTL mode and probably use an unregulated linear power supply consisting of a toroidal power transformer, bridge rectifier and RC filter.

[wushuliu]

wushuliu,

I just picked up on this thread, so I thought I would chime in here about my latest experiences with the Texas Instruments TPA3255EVM Class D amplifier. I purchased this during the 50% off sale at TI, and then purchased a Mean Well LRS-350-48 switching power supply from Arrow for about $31.

thanks for the update Rich! Can't wait to hear your thoughts on the PFFB...

[rhing]

I caved in and purchased another TI TPA3255EVM amplifier at half-off, so I can run the amps in PBTL (mono) mode. I’ll have to get parts to assemble an unregulated linear power supply to power both amp modules with a reasonable amount of current.

To implement PFFB, I am waiting on a few parts from Mouser on back-order, but I may check out Digikey to see if they have similar components in stock.

[wushuliu]

I caved in and purchased another TI TPA3255EVM amplifier at half-off, so I can run the amps in PBTL (mono) mode. I’ll have to get parts to assemble an unregulated linear power supply to power both amp modules with a reasonable amount of current.

To implement PFFB, I am waiting on a few parts from Mouser on back-order, but I may check out Digikey to see if they have similar components in stock.

I came across the discussion on these at Klipsch forum recently. Did someone there compare linear PS to SMPS? I'd like to, but that would mean a new enclosure with pre-cutouts for mains,  a giant expensive toroid, etc. etc.

[rhing]

I came across the discussion on these at Klipsch forum recently. Did someone there compare linear PS to SMPS? I'd like to, but that would mean a new enclosure with pre-cutouts for mains,  a giant expensive toroid, etc. etc.

wdecho didn’t actually compare a linear versus switching power supply for the TI TPA3255EVM, he just pieced together a nice unregulated linear power supply with many components he already had. Others like me went the lazy man’s route and purchased switching power supplies like the Mean Well LRP-350-48. What he did do was compare the TI TPA3255EVM to some of the Pass DIY First Watt amplifier clones he had, and the TI Class D compared favorably.

Hopefully, my other TPA3255EVM will arrive soon, and I will begin building an unregulated linear power supply. A good primer can be found here:
http://www.decdun.me.uk/gainclone_psu.html

Gainclone chip amps typically run off dual rail power supplies, but much of the information presented in this Web article can be applied to single rail power supplies like those that the TI TPA31xx and TPA 32xx Class D amps require.

[flavo]

3E has been out of his power supply for a while now and he recommended I look into a Meanwell unit. Is the LRS-350-48 the go to or should I be looking at some other options.
Thanks so much.

[rhing]

3E has been out of his power supply for a while now and he recommended I look into a Meanwell unit. Is the LRS-350-48 the go to or should I be looking at some other options.
Thanks so much.

I use a Mean Well LRS-350-48 to power my TI TPA3255EVM amp, and it is quiet. I’ve never had the cooking actually turn on, since it never gets hot. I use 14ga PVC-insulated Copper wire from an IEC power cable to connect the power supply to the amp. Arrow sells these for about $30. 

[renaudrenaud]

In 2015 I was musing on internet and discovered Flea Watt website and on a picture, I was able to understand the card was a TPA3116. At this moment I bought few cards to test, from Yuan Jing audio.

Then I want to China for 2 years. Without too much equipment to listen to music. In the city of Xi'an, I did not find shops to rebuild something acceptable, so I build for myself my system, using TPA3116... The cost is ridiculous and audio quality is not in direct relation with the price. After few weeks I got a very decent system.

I am also on the Texas Instrument mail list since years. I do not remember when, but few years ago I received a mail about the new high quality high power TPA3255. At this time the EVM was maybe at 300$. I checked on the Chinese side and there was no low cost card. At this time I tought the price of the EVM was to much for just curiosity and I was not completely satisfied with the Class D: I already have plenty of amplifiers, tubes, transistors, in different classes and even if some are worst than the TPA3116, plenty are better than it in term of audio quality.

In China there is the great numeric wall and I was not easily able to go on the TI website. Anyway, I am back in France since few months, and in november I received a mail from TI: the EVM was 50% off and the price was only 150$. So I went for 2 cards - in case I need 2x600W...

I received the cards and then was able to use one sample only one week before the holidays.

I tried few things. The lowest voltage is 15V. I tried batteries power, laboratory power and a power block for a computer, the same I use for the TPA3116.

I tought the lover voltage the lower level in term of sound pressure. It is not true. Less voltage means more distorsion and clipping when you turn the volume button.

I do not like the sound of the card with only 20V power unit.

I have tried with batteries: one batt around 30V, and also powerfull batt around 50V able of 200A in continuous.

I then started to use a lab power around 30V. With this power unit, the sound quality was enough. I can see the consumption on the power lab and at 30V, with speakers around 90dB of efficiency, the Amps are between 0.12 and 0.14 when I listen to music. When there is no music, EVM On, the consumption is between 0.1 and 0.11.

When I want to listen a bit louder, this is mainly less than 1A... But depending on the program, it could raise immediately to 10x this value.

I am happy for the moment with the power lab I am not able to detect difference with the big pack of batteries. Anyway, I will use another and more powerful Lab power when I will be back.

Also, I was afraid of so many watts with my little pair of speakers (for the moment) but the amp is not a brutal one (it could anyway). There is no noise, hum or anything annoying even putting the ear at 1cm of the speaker.

In term of sonic performances, the EVM Card is far far far from the TPA3116. I was happy to connect some of nice gear (for the moment plenty of my equipment is not at home) and the EVM board is incredible. I am impatient to use an XLR connection to the card and test it with different sources.

I think I will buy  low cost TPA3255 from China to compare, but for the price, the EVM is completely incredible.

Class D is in good hands with TI and this is only the beginning.


http://fleawatt.blogspot.fr/
https://www.yuan-jing.com/