Class D Amplifier

[sunilmani]

Planning on building a good quality stereo, class D amplifier within 20K INR. I am looking at readymade boards and to the extent possible, with onboard power supplies. As of now i am looking at ICE Power boards; but i am open to others as well. Appreciate any suggestions around this.

Edit:
ICE 50ASX2 and ICE125ASx2 both seem to fit. The prices on part express is on the higher side. The same seems to be available on AliExpress. Anyone having experience with this one on Ali express?

 

[sound1]

I built kit from below and perfectly happy. There is a $199 CDA 250 kit and supposedly good.

SDS-250 Power Amplifier Kit

SDS-250 Audio Power Amplifier Kit with large power supply and 400VA Antek transformer. Featuring State-of-the-Art balanced or single ended inputs and adjustable gain. RMS power is 250 Watts X 2 into 4 Ohm, 125 Watts X 2 into 8 Ohm, and 500W into 8 Ohm in Bridged Mode. Wired Molex connectors and...

classdaudio.com

 

[SanjeevM]

I have made my Amp with the Texas Instruments TPA3255 evaluation board. It's a wonderful class D amplifier. I am enjoying it. It costs $155 and can be bought from mouser.in. The power supply is a Meanwell LRS-350-48 which is another 4000/- odd.

If you want the best in class D, go for Hypex NCORE amplifier boards. They are expensive, though.

 

[sunilmani]

I built kit from below and perfectly happy. There is a $199 CDA 250 kit and supposedly good.

SDS-250 Power Amplifier Kit

SDS-250 Audio Power Amplifier Kit with large power supply and 400VA Antek transformer. Featuring State-of-the-Art balanced or single ended inputs and adjustable gain. RMS power is 250 Watts X 2 into 4 Ohm, 125 Watts X 2 into 8 Ohm, and 500W into 8 Ohm in Bridged Mode. Wired Molex connectors and...

classdaudio.com

Thanks for your suggestion. Will surely check on this one before finalizing.

I have made my Amp with the Texas Instruments TPA3255 evaluation board. It's a wonderful class D amplifier. I am enjoying it. It costs $155 and can be bought from mouser.in. The power supply is a Meanwell LRS-350-48 which is another 4000/- odd.

People swear by this chip. I have read some reviews on the chip and they are good. The power supply seems a bit tough to get. Let me check on that

If you want the best in class D, go for Hypex NCORE amplifier boards. They are expensive, though.

NCORE is way beyond my budget. I did read about them, but for now, i would not go for them

 

[SanjeevM]

Here is one source for the Meanwell.

https://www.electronicscomp.com/lrs-350-48-mean-well-power-supply-350w-48v-7.3a?gclid=Cj0KCQjwl8XtBRDAARIsAKfwtxCpvGRuDBUagONxz-SYrE_lOn90-Hw9K8huRr767gbx_H492wnyPOkaAqtwEALw_wcB

 

[Rud31]

I bought a Meanwell PSU from them 48V 12.5A 600W for my TPA3255 based 2.1.Barring the noisy fan, it works like charm.

 

[sunilmani]

I bought a Meanwell PSU from them 48V 12.5A 600W for my TPA3255 based 2.1.Barring the noisy fan, it works like charm.

Thanks for letting me know about the fan noise. Will keep that in mind

Here is one source for the Meanwell.

https://www.electronicscomp.com/lrs-350-48-mean-well-power-supply-350w-48v-7.3a?gclid=Cj0KCQjwl8XtBRDAARIsAKfwtxCpvGRuDBUagONxz-SYrE_lOn90-Hw9K8huRr767gbx_H492wnyPOkaAqtwEALw_wcB

I too found this one last night while searching.

Anyone having experience with IRS 2092 ? Appreciate any feedback about it.

 

[SanjeevM]

Meanwell PSU is very good.

 

[saikatbiswas82]

Anyone having experience with IRS 2092 ? Appreciate any feedback about it.

After experimenting with various class d amps, I'm settled with IRS2092s only.

Trust me there are so many unwanted design flaws with other el cheppo class d amp boards.

The best TPA based amps I've heard so far is - Allo Vold+D. Still it has a manual mute switch for controlling start up/shut down thump.

Currently I'm building my gear around 6 IRS2092 (LJM L15-D PS) monoblocks (3 way active tower). These amps are having enough power, clean sounding and has a built in speaker protection which gives me a peace of mind.

Please remember that most class d amps have very low input impedence. So in case you are planning to jump into class d, make sure your source output impedence is less than or equal to 200ohm. Otherwise plan for a input buffer stage.

My next venture would be Hypex NCores.

Hope that helps.

 

[SanjeevM]

THD+N Comparison::

IRS2092 is 0.01% at 50W 4ohm
TPA3255 is 0.005% at 50W 4ohm.

 

[sunilmani]

After experimenting with various class d amps, I'm settled with IRS2092s only.

Trust me there are so many unwanted design flaws with other el cheppo class d amp boards.

The best TPA based amps I've heard so far is - Allo Vold+D. Still it has a manual mute switch for controlling start up/shut down thump.

Currently I'm building my gear around 6 IRS2092 (LJM L15-D PS) monoblocks (3 way active tower). These amps are having enough power, clean sounding and has a built in speaker protection which gives me a peace of mind.

Please remember that most class d amps have very low input impedence. So in case you are planning to jump into class d, make sure your source output impedence is less than or equal to 200ohm. Otherwise plan for a input buffer stage.

My next venture would be Hypex NCores.

Hope that helps.

Thanks for the suggestion Saikat.

THD+N Comparison::

IRS2092 is 0.01% at 50W 4ohm
TPA3255 is 0.005% at 50W 4ohm.

I was reading on the THD parameter. So, i have not heard the 3255 nor the 2092. So, can one really make out the difference between a 0.01
% THD and 0.005%THD ?

 

[saikatbiswas82]

THD is not a decision making factors for amps IMHO. Look at tube amps. By that factor, you'll hate tube amps at first glance until you listen to one.

Doesn't always matter which ic is being used in any device. It always boils down to the design.

Always listen and decide.

My mind.

 

[SanjeevM]

Well, a lower noise floor allows more smaller sounds to be heard. Like the decaying sound of a bell, small tinkle played by the orchestra, the rubbing of the fingers on a guitar wire, etc. The Amp becomes more detailed.

The tube sound you talk about, is concerned with harmonics. Tube sounds smooth because of 2nd order harmonics. It's not so much about noise.

My $0.02.

Regards.

 

[diyaudio]

THD has been used (abused) by clever marketing. A low THD figure is claimed to perform better. Well, thats true in the case of electronics in general but not audio. I ve said this before elsewhere on this forum, a 1% distortion of higher order will sound horrible as compared to 10% low order distortion. The human ear/brain auditory system is very forgiving to low order distortion, in fact it 'prefer's low order distortion. Ask valve guys The valve amp is bound to have higher THD if we leave the marketing aside and actually measure independently.

Lets look at a max distortion of a decent class D amp, we notice its around 5.5khz. Now the 2nd harmonic is at 11khz, which is already in treble range and that is not critical, the next harmonic is at 22Khz which we cant hear, maybe bats could find it objectionable

As far as a bit of noise: GSM telephony technology does add noise in certain case to make the sound more legible .
Hunting absolute figures will not get us anywhere. Its time we embraced class D, technology has moved ahead and so must we.

 

[Amarendra]

Planning on building a good quality stereo, class D amplifier within 20K INR. I am looking at readymade boards and to the extent possible, with onboard power supplies. As of now i am looking at ICE Power boards; but i am open to others as well. Appreciate any suggestions around this.

Edit:
ICE 50ASX2 and ICE125ASx2 both seem to fit. The prices on part express is on the higher side. The same seems to be available on AliExpress. Anyone having experience with this one on Ali express?

Try the TDA 7498E amplifier board. It’s available on aliexpress. You will need a good preamp to manage it.

 

[SanjeevM]

Please see this page too.

Comparing some Class D amps

Hello. From several month ago, i have found Class D amp for me. Finally i arrived journey's goal. For comparison amps, bought its from Aliexpress and ebay for 3 months, TPA3116, TDA7498, TPA3255(EVM), TAS5613, STA516B (AB32516). First time, i bought 3116, 7498. 3116 was just bought, not use...

www.diyaudio.com

 

[sunilmani]

Please see this page too.

Comparing some Class D amps

Hello. From several month ago, i have found Class D amp for me. Finally i arrived journey's goal. For comparison amps, bought its from Aliexpress and ebay for 3 months, TPA3116, TDA7498, TPA3255(EVM), TAS5613, STA516B (AB32516). First time, i bought 3116, 7498. 3116 was just bought, not use...

www.diyaudio.com

Thanks for the suggestion SanjeevM

I am kind of tending towards TPA3255. In parallel i was searching for a box to house it. I was looking for one to house the supply and amp board to gehter; should have a volume control space along with 4 channel selection switch. I have looked through many websites, not able to get the right one at decent price point. Appreciate any suggestions in this matter.

 

[SanjeevM]

That's easy. The advantage of Class D is that the components are very light, no heavy trafos to use. If you can find a metal box, it'd OK, but otherwise you can just design your cabinet in MDF or transparent Acrylic and house the amplifier. You can get the design laser cut and joined using superglue. Make a Coreldraw file from which you can get laser cutting done. I made my cabinet out of both materials. And it's good looking.

 

[tuff]

That's easy. The advantage of Class D is that the components are very light, no heavy trafos to use. If you can find a metal box, it'd OK, but otherwise you can just design your cabinet in MDF or transparent Acrylic and house the amplifier. You can get the design laser cut and joined using superglue. Make a Coreldraw file from which you can get laser cutting done. I made my cabinet out of both materials. And it's good looking.

Can you post some pics of it. I myself am also in the process of building a box for the pre-amplifier i am using currently.

 

[sunilmani]

That's easy. The advantage of Class D is that the components are very light, no heavy trafos to use. If you can find a metal box, it'd OK, but otherwise you can just design your cabinet in MDF or transparent Acrylic and house the amplifier. You can get the design laser cut and joined using superglue. Make a Coreldraw file from which you can get laser cutting done. I made my cabinet out of both materials. And it's good looking.

Surely a picture would help. I can get the material and make the drawings, but i am not sure on the laser cutting part. Will need to check on it in my city.