Hi Tom,
the problem is solved and I got sound from my speakers, thank you! 🙂
Two things I found for myself:
I have several versions of the reason why it could be:
the problem is solved and I got sound from my speakers, thank you! 🙂
Two things I found for myself:
- maximum voltage in the speakers terminals without load is around 6V
- I got much less bass comparing to my old Denon PMA-1500
I have several versions of the reason why it could be:
- ow voltage and gain, because I use unbalanced connection shorting 1 and 3 pins to the ground - is it better to use unbalanced-to-balanced converter?
- I need to warm up the amp for some time (not sure if it's true - just following recommendations from audiophiles)
- I need to get used to the sound of the new amp - no EQ or any other bass busters
So with the volume knob cranked to the max you're only getting 6 V output? Are you running in unity gain? The Purifi 1ET400A should be able to get up near 40 V RMS at the output.
There are a couple of reasons this could be:
If the performance of the amp depended significantly on temperature or aging I would be severely disappointed in the engineering at Purifi (and in my own engineering for that matter).
Tom
There are a couple of reasons this could be:
- You're measuring at a frequency that's beyond the bandwidth of your voltmeter. Measure at 400 Hz as most DMMs can handle that.
- Your preamp has really, really low output. Have you measured it?
If the performance of the amp depended significantly on temperature or aging I would be severely disappointed in the engineering at Purifi (and in my own engineering for that matter).
Tom
That's fantastic.
Recently bought the 1ET9040BA module but didn't buy the input buffer and realized the input buffer might be too challenging for me to keep the good SNR...
And I'm also deciding on choosing the SMPS for 1ET9040BA. It seems most people use hypex SMPS for the module including your tutorial video. Will there be benefits using Mean Well SMPS for class D amplifiers? It seems a good option for your modulus series amplifiers.
Most of the audio SMPS seems to be unregulated SMPS and provides higher peak power and if the current draw is too large it'll just drop the supply voltage instead of tripping OCP.
But the new Nilai SMPS PS500DIY is said to be a regulated one which has tight output voltage range (69-71V). It seems to be a good SMPS for class D audio amplifier but unfortunately the voltage is too high for the 1ET9040BA module.
The Mean Well LRS N2 series can output 200% peak power which sounds like a good option for audio.
Recently bought the 1ET9040BA module but didn't buy the input buffer and realized the input buffer might be too challenging for me to keep the good SNR...
And I'm also deciding on choosing the SMPS for 1ET9040BA. It seems most people use hypex SMPS for the module including your tutorial video. Will there be benefits using Mean Well SMPS for class D amplifiers? It seems a good option for your modulus series amplifiers.
Most of the audio SMPS seems to be unregulated SMPS and provides higher peak power and if the current draw is too large it'll just drop the supply voltage instead of tripping OCP.
But the new Nilai SMPS PS500DIY is said to be a regulated one which has tight output voltage range (69-71V). It seems to be a good SMPS for class D audio amplifier but unfortunately the voltage is too high for the 1ET9040BA module.
The Mean Well LRS N2 series can output 200% peak power which sounds like a good option for audio.
Any idea on cost and gain(s) setting you plan on? I am looking at one commercial 9040 monoblock set but learned the gain isn't really a great match for my 4.2V output dac (Okto dac8) so I am considering diy at the moment so I can get the gain I want, speakons, etc. Thanks.
Buying SMPS is a bit tricky...the term "regulated" in conjunction with a mains power supply mean that the output voltage is regulated with respect to the mains - the supply don't vape its output if the mains varies. But I don't think it necessarily means that the DC is regulated during stable mains... this is perhaps what you are saying... What to look for in order to get a SMPS that has a constant DC output during load?
//
FWIW, the folks at Purifi use the Hypex SMPS1200A180 for the 9040BA.
I like the Mean Well supplies, but getting all the voltages you need for the Purifi amps will be a pain. You need the main ±65ish V. Then you need the auxiliary supply. You also need a 15 V drive supply referenced to V-. You'll end up with this Medusa head of five supplies.
If you don't like Hypex (which you can buy through https://www.diyclassd.com/) Micro Audio in Jordan might be an option for you.
I'm aiming for 26 dB gain, total, with a custom option to set it however you'd like it. No idea of the cost, only that it'll be more expensive than my current Purifi 1ET400A buffer.
Tom
I like the Mean Well supplies, but getting all the voltages you need for the Purifi amps will be a pain. You need the main ±65ish V. Then you need the auxiliary supply. You also need a 15 V drive supply referenced to V-. You'll end up with this Medusa head of five supplies.
If you don't like Hypex (which you can buy through https://www.diyclassd.com/) Micro Audio in Jordan might be an option for you.
I'm aiming for 26 dB gain, total, with a custom option to set it however you'd like it. No idea of the cost, only that it'll be more expensive than my current Purifi 1ET400A buffer.
Tom
I won't say I don't like Hypex.
It's just when I reading the combination of SMPS I did read someone mentioned about the Micro Audio's SMPS is a step forward compare with Hypex's so that triggers me to search more options for the Purifi module...
Yes indeed the SMPS1200A180 seems to be the most reasonable option that won't go wrong. There's too many rail to provide for the 1ET9040BA.
Looking forward to your following buffers.
It's just when I reading the combination of SMPS I did read someone mentioned about the Micro Audio's SMPS is a step forward compare with Hypex's so that triggers me to search more options for the Purifi module...
Yes indeed the SMPS1200A180 seems to be the most reasonable option that won't go wrong. There's too many rail to provide for the 1ET9040BA.
Looking forward to your following buffers.
Both seem like good options to me.
Soon. Until the circuit is in production I won't commit to a date.
Tom
I once saw an interview with Bruno about the new input buffer using the OPA1656. I remember that the OPA1612 still has lower distortion on paper, but they see some benefits in input impedance, so they chose the OPA1656 for the new buffer board.
Though it seems that every op-amp should be transparent enough today...
edit: add youtube link
Though it seems that every op-amp should be transparent enough today...
edit: add youtube link
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FWIW, Micro Audio has the SMPS1K-SN for the 1ET9040BA rated @ 1,300W.
MicroAudio SMPS1K-SN
Data Sheet - PDF
Options:
Accepts additional output capacitors up to 140000uF based on mode
Yeah. MicroAudio is the real deal. I've had a few email conversations with Sami who runs it and I like his approach to engineering, including that he has his products certified to make sure they meet standards for EMC, electrical safety, etc. I have only limited experience with his products but have been impressed so far.
Tom
Tom
I should have the first prototype boards this coming week. Are you interested in being a beta tester and plugging them into your 9040?
Tom
Tom
I would if I had some !!! 🙂
I am interested in the 9040's higher output over the original 400A.