I'm looking to build a class D PA for my Dahlquist DQ-10s. I've been using a Class A DH-500 for years, but with the new digital inputs (Sonos), I want the flexibility of a class D so I can leave it on all the time. Problem is, I need 250W a side, and it doesn't appear that there's lots of that.
I'd like to build two monoblocks and use my Hafler chassis to house it all. Problem is, I don't know where to start. I do have some experience - built the DH-500 and have modded the crossovers in the DQ-10s, but I'm really a noob.
Any ideas?
I'd like to build two monoblocks and use my Hafler chassis to house it all. Problem is, I don't know where to start. I do have some experience - built the DH-500 and have modded the crossovers in the DQ-10s, but I'm really a noob.
Any ideas?
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Yeah - I saw that. Nobsound has a build on Amazon. Do you know this chip/board? Is it easy to design?
TPA3255 is very good sound-wise. Chris is very experienced with TPA3255. An alternative with more than 250W power is a IRS2092 based amplifier. Nigel is very proficient with IRS2092.
I have nothing that powerful.
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If you were experienced in desingning conventional class a/b amps - designing the class d-amp will be a challenge. And if you are a noob, this might be a long and frustrating road to nowhere. So I would recommend some readyly build modules. Some years ago I bought a couple of 250W Modules from SEEEDStudio - these work still flawlessly in the pub where I installed them.
I can say from experience that attempts in designing discrete class-D amps has resulted in a lot of magic smoke being released. Designing IC based solutions (and you can find ICs that can handle around the power levels you are after) is a lot easier!
Failing that I have had great experience with the Sure amps (but not their integrated bluetooth and DSP amps):
Sure Electronics' webstore Mid Power Audio Amplifier (30-300W per channel)
Failing that I have had great experience with the Sure amps (but not their integrated bluetooth and DSP amps):
Sure Electronics' webstore Mid Power Audio Amplifier (30-300W per channel)
Thanks for the roses FF
but seriously i am not an developer an expert....i trying around with nooby things at this board...https://www.diyaudio.com/forums/class-d/309813-wrong-tpa3255-70.html#post5654349
i just try and learn with these chinese TPA3255 board. if you read in this threat
you will realize that this implementation is not build for 300W as the chip can do.
This is the reason way its better to buy a TI or 3E board TPA3255.
the irs2092 i do not know.
once again....are you really sure that you need 250W and more.....before i start with diy (still nooby)...i bought and rent a lot of amplifier and i swore that bigger is better ......now i know it a little better.....
power is nothing with control = >...less thd and noise etc...
chris
I didn't realize that. I did some cap mods a few years back, but didn't really notice a difference. No heatsinking.
It's the heat and power draw that's making me sadly want to leave this Hafler behind. With today's electronics, I want my amplifier to be turned on by the 'Smart stuff' and I don't want it idling away in kilowatts ;-)
Thanks for the roses FF
once again....are you really sure that you need 250W and more.....before i start with diy (still nooby)...i bought and rent a lot of amplifier and i swore that bigger is better ......now i know it a little better.....
power is nothing with control = >...less thd and noise etc...
chris
The Dahlquists need power. I remember a few years back trying to run them off of a 60W/side PA and nada!
Now that would be sweet.
Regrettably ‘no distortion’ isn’t a thing we have invented yet! The 3255 has lower distortion and higher power (but will need a larger power supply to achieve those higher powers). I personally have not used any 3255 boards but honestly I don’t think you will be disappointed with a 3116D2 based design. The bigger influence on quality will be the complimentary components chosen on the board. You can look at upgrading these yourself:
www.diyaudio.com/wiki/TPA3116D2_Boards
www.diyaudio.com/wiki/TPA3116D2_Boards
You may be right, but I always thought it was Class A, and the heatsinks are indeed massive, but really neat. The two boards are mounted on adjacent sides of a fin-block that's hollowed out to make a finned fan duct. Pretty efficient thermally.
Here are the Hafler specs: (Note 1200 VA @ rated power into 8 ohms
)Power Rating: Less than 0.025% total harmonic distortion at any power level up to 255 watts continuous average power per channel into 8 ohms at any frequency between 20 Hz and 20 kHz with both channels driven.
IM Distortion (SMPTE): Less than 0.007% from 1 watt to 255 watts into 8 ohms
Typical THD at 255 watts into 8 ohms: 1 kHz-0.002%; 10 kHz-0.007%
Frequency Response into 8 ohms:-3 dB, 0.5 Hz to 120 kO.5 dB, 5 Hz to 40
Typical Channel Separation at 1 kHz: 60 dB kHz at 1 watt kHz at 255 watts
Signal to Noise Ratio: Exceeds 100 dB referred to 255 watts into 8 ohms, unweighted Exceeds 90 dB referred to 1 watt into 8 ohms, A weighting Input Impedance: 47,000 ohms
Input Sensitivity: 2.35 volts for 255 watts into 8 ohms; 0.145 volts for 1 watt
Damping Factor: 200 to 1 kHz into 8 ohms; 60 to 10 kHz into 8 ohms
Rise Time: 10 kHz, 80 volts p/p square wave, 10% to 90%: 2.5 us.
Slew Rate: 1 kHz, 120 volts p/p square wave: 45 V/us.
Semiconductor Complement: 27 transistors, 12 power Mosfets, 33 diodes, 8 zener diodes, one integrated circuit, one diode bridge.
Power Consumption: 240 VA quiescent; 1200 VA @ rated power into 8 ohms, 2 channels
Size: 7-l/4” high, 19” wide, 13” deep including handles
Net Weight: 45 lbs.
Shipping Weight: 49 lbs.
Isn't the Hafler PS going to be a poor match for any of these TPA's? Aren't they typically designed for single supply operation? The Hafler is probably +/-75V.
From somebody whose been around since Haflers were state-of-the-art, I'd hate to see a working one chopped just for the PS of a Class D chipamp.
-Rick
From somebody whose been around since Haflers were state-of-the-art, I'd hate to see a working one chopped just for the PS of a Class D chipamp.
-Rick
Don't have a plan yet. Just investigating. I want something to replace the Hafler, and a friend showed me the TI datasheet, and somehow I wound up here. I can't do boards, but I can do system or buy a DIY that powers the Dahlquists.
I remember looking at an amp called the n-something about 10 years ago. It was a D and it sounded great. They no longer make it however. It was out of my range anyway.
Thanks!
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