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Re: Curiosity gets the better of me (again)
Posted: Tue Jan 31, 2023 9:06 pm
by karatestu
The small size of the amps is remarkable. One in each pocket
my only exposure to Class D is my JBL Bluetooth jobbie. Nothing to complain about there. Although its not a fair comparison with my main equipment which is in a completely higher stratosphere.
The chip probably has more than one power pin , each one ought to be powered from a different regulator (one would hope). It can get really interesting when however many regulators there are, are given their own dedicated psu (right back to separate transformers). I did that with my cdp and the dac chip alone has three psu's, the fancy clock another anc thd iriyinal psu powering thd rest. If i hadn't bypassed the six opamps in the output stage i would have ended up with a shed load more.
Sometimes I find you just can't go far enough with separating things out. If your speakers are wired for biamping then get another two of the blighters - balance control and tone control
You might get tired of adjusting four volume controls though
Re: Curiosity gets the better of me (again)
Posted: Tue Jan 31, 2023 9:49 pm
by Firebug1
Don't know about UK and Holland, but at least here in Finland, class d amps are quite popular DIY projects. Boards are reasonable priced and quite easy to put together, if I have understood correctly.
Re: Curiosity gets the better of me (again)
Posted: Tue Jan 31, 2023 9:50 pm
by Geoff.R.G
karatestu wrote: ↑Tue Jan 31, 2023 9:06 pm
The small size of the amps is remarkable. One in each pocket
my only exposure to Class D is my JBL Bluetooth jobbie. Nothing to complain about there. Although its not a fair comparison with my main equipment which is in a completely higher stratosphere.
The chip probably has more than one power pin , each one ought to be powered from a different regulator (one would hope). It can get really interesting when however many regulators there are, are given their own dedicated psu (right back to separate transformers). I did that with my cdp and the dac chip alone has three psu's, the fancy clock another anc thd iriyinal psu powering thd rest. If i hadn't bypassed the six opamps in the output stage i would have ended up with a shed load more.
Sometimes I find you just can't go far enough with separating things out. If your speakers are wired for biamping then get another two of the blighters - balance control and tone control
You might get tired of adjusting four volume controls though
Stu, depending on the chip, the power pins may be connected together inside. Always worth checking before supplying each pin from a different PSU.
Re: Curiosity gets the better of me (again)
Posted: Tue Jan 31, 2023 11:39 pm
by NSNO2021
I am also intrigued by the advances of class D Amps, especially when the likes of Nelson Pass is saying the very best class D Amps are getting to be very good then you have to acknowledge the rate of progress is impressive.
Re: Curiosity gets the better of me (again)
Posted: Wed Feb 01, 2023 6:25 am
by karatestu
Geoff.R.G wrote: ↑Tue Jan 31, 2023 9:50 pm
karatestu wrote: ↑Tue Jan 31, 2023 9:06 pm
The small size of the amps is remarkable. One in each pocket
my only exposure to Class D is my JBL Bluetooth jobbie. Nothing to complain about there. Although its not a fair comparison with my main equipment which is in a completely higher stratosphere.
The chip probably has more than one power pin , each one ought to be powered from a different regulator (one would hope). It can get really interesting when however many regulators there are, are given their own dedicated psu (right back to separate transformers). I did that with my cdp and the dac chip alone has three psu's, the fancy clock another anc thd iriyinal psu powering thd rest. If i hadn't bypassed the six opamps in the output stage i would have ended up with a shed load more.
Sometimes I find you just can't go far enough with separating things out. If your speakers are wired for biamping then get another two of the blighters - balance control and tone control
You might get tired of adjusting four volume controls though
Stu, depending on the chip, the power pins may be connected together inside. Always worth checking before supplying each pin from a different PSU.
Of ourse Groff, always read the data sheet. I would say though that if each pin already has its own regulator then it shouldn't be directly connected inside ?
Re: Curiosity gets the better of me (again)
Posted: Wed Feb 01, 2023 8:35 am
by Geoff.R.G
NSNO2021 wrote: ↑Tue Jan 31, 2023 11:39 pm
I am also intrigued by the advances of class D Amps, especially when the likes of Nelson Pass is saying the very best class D Amps are getting to be very good then you have to acknowledge the rate of progress is impressive.
It has taken 65 years! Admittedly most of that time was spent waiting for suitable semiconductors but the rapid progress hasn't been quite as impressive as it might look.
Re: Curiosity gets the better of me (again)
Posted: Wed Feb 01, 2023 11:33 am
by Fretless
Chopping & changing. Hooked up a spare set of speakers to the Douk G4 for a blast. These are (Dutch) Audiolab Minax that I Doc-Modded back in 2015 and used as my main speakers for a while.
These boxes have a troublesome tweeter that is rather shrill and has been Plasti-dipped to tame it. With the Class D amps this shrillness was unpleasantly overbearing and it is obvious that this combination isn't going to work.
Attaching the Minax to the old warhorse Kenwood KA-4010 was a different story, sounds great! So this has freed up the G4's and the Mission 760's for an alternative setup that is taking shape.
Now I just need some speaker cables, wonder what there is on Amazon?
Re: Curiosity gets the better of me (again)
Posted: Wed Feb 01, 2023 12:52 pm
by Fretless
Result!
If you look closely you can see the two tiny Douk G4 amps tucked under the monitor of my home office desktop. Nicked the speaker cables (NVA LS5) temporarily from the music workstation and have ordered a short pair of Douk's own OFC speaker leads from Amazon, may be in tomorrow.
For now this is doing exactly what I wanted it to do ...
.... make music!
Re: Curiosity gets the better of me (again)
Posted: Wed Feb 01, 2023 6:01 pm
by CN211276
Geoff.R.G wrote: ↑Wed Feb 01, 2023 8:35 am
It has taken 65 years! Admittedly most of that time was spent waiting for suitable semiconductors but the rapid progress hasn't been quite as impressive as it might look.
Interesting. It predates digital playback, where there has been rapid progress in the past decade, by some.
Re: Curiosity gets the better of me (again)
Posted: Wed Feb 01, 2023 8:20 pm
by Geoff.R.G
CN211276 wrote: ↑Wed Feb 01, 2023 6:01 pm
Geoff.R.G wrote: ↑Wed Feb 01, 2023 8:35 am
It has taken 65 years! Admittedly most of that time was spent waiting for suitable semiconductors but the rapid progress hasn't been quite as impressive as it might look.
Interesting. It predates digital playback, where there has been rapid progress in the past decade, by some.
I was surprised too, I thought I was a much more recent development.