Interesting. I ask because the TPA3100, 3110, and I think 3123 boards I have don't have snubbers and the TPA3116 spec sheet has the same blurb that is in all their pdfs that:
Additional EMC improvements may be obtained by adding snubber networks from each of the class-D outputs to
ground. Suggested values for a simple RC series snubber network would be 18 Ω in series with a 330 pF
capacitor although design of the snubber network is specific to every application and must be designed taking
into account the parasitic reactance of the printed circuit board as well as the audio amp.
The 3116 sheet is the only one that actually has snubber network in the schematic.
Last edited:
For those of us in North America Hifimediy is now carrying Connex power supplies. There is a 28v w/ 10% adjustability definitely doable for the TPA3116. Hard to beat the size, quality, and even auxiliary power for 10-12v preamp.
Just because they are not fitted doesn't mean they are not desirable.
Maybe if the amplifier is part of a powered speaker where the manufacturer has control of the amplifier layout, speaker lead length and type of speaker then it may be omitted after testing. Unknown speaker lead lengths and load impedance are a different matter. I would prefer to have some form of protection due to loading than risk destroying the amplifier. In some application notes the snubber is said to improve the THD performance so a good reason to leave it in for the sake of a few pence, cents or whatever.
Maybe if the amplifier is part of a powered speaker where the manufacturer has control of the amplifier layout, speaker lead length and type of speaker then it may be omitted after testing. Unknown speaker lead lengths and load impedance are a different matter. I would prefer to have some form of protection due to loading than risk destroying the amplifier. In some application notes the snubber is said to improve the THD performance so a good reason to leave it in for the sake of a few pence, cents or whatever.
Please keep in mind the TPA3116 has overvoltage shutdown at 27V +0%/-10%, so it might shutdown even when power supply is adjusted to minimum setting.
I finished the first of three TPA3116 based amps.
This box started out as part of a a cheap Tivoli knockoff am/fm radio.
I like the simplicity of it's appearance.
These boards really offer good performance for the money.
This box started out as part of a a cheap Tivoli knockoff am/fm radio.
I like the simplicity of it's appearance.
These boards really offer good performance for the money.
Attachments
You should really think about selling. That is really cool. Again, that is serious hipster bait gear.
Speaking of hipster bait audio. That amp would go great with something like this.
Love the Cardas posts. They are the best.
I hope you are joking because that is a beyond stupid statement if you're serious.
Please explain how?
It's the same plinth, tone arm, motor, motor suspension, and drive design. Even down to the detail of using a glass platter for added weight to improve wow/flutter. The only real difference is the position of the drive band which is copied from another late 1980s/early 1990s design which name escapes me at the moment.
Last edited:
Not too many shots of the internals because once you start lashing it all together, it's a tight squeeze to take pics inside of it, but here's what I have.
Attachments
Forgot to ask before: what's the green cap value you have bypassing the dc input?
That cap was actually replaced with something else before final assembly, but it is a .1/63V ERO
KJA,
Wow, you did it again!! That looks really cool!
Is that a SMPS? Did you buid that too?
Regards,
Thanks!
Making these DIY amps look nice is new territory for me. My projects typically look functional but not very aesthetic, so it's been fun trying to spruce them up a bit. The next one is pretty interesting looking, but it's a ways off from being done.
Inside is a 20V 5A laptop power supply that I had to remove the case from so that it would fit inside the box.
I usually like to use external power supplies but this time I was compelled to fit everything in the box.
Thanks! Those are m favorite posts too. Bring on the hipster$!
(They would go great together)
FYI, I followed the recommendations from the filter pdf for my 4 ohm speakers - 15uh (Bourns) and 3.3uf wima poly. swapped the 10uf ceramics for 3.3uf pp I had laying around; the 10uf was too strong in mid-bass. Sounds nice and balanced now with terrific midrange quality.
Also just noticed that the gain for the ebay 2.0 board is 26db. For some reason I thought it was 36 max gain. No wonder the 10uf was too much. I'll probably increase the gain as I preferred it when I had the 3100D2 board.