Thanks for the info, I've been waiting impatiently for your report on these amps 
BTW, what do you use for the power source?
I'm thinking of using a pair for a simple "dual mono" config, and I'm not sure how to power such a config... Would a single SMPS be OK, with a diode divider, perhaps?
Somehow it seems silly to put them in separate enclosures (monoblocks) with separate SMPS power bricks for each... as they are so tiny
Although, I guess that would be best for a pure stereo config, with each monoblock enclosure close to the speaker and short speaker wires...
BTW, what do you use for the power source?
I'm thinking of using a pair for a simple "dual mono" config, and I'm not sure how to power such a config... Would a single SMPS be OK, with a diode divider, perhaps?
Somehow it seems silly to put them in separate enclosures (monoblocks) with separate SMPS power bricks for each... as they are so tiny
Although, I guess that would be best for a pure stereo config, with each monoblock enclosure close to the speaker and short speaker wires...
Thanks for the info, I've been waiting impatiently for your report on these amps
BTW, what do you use for the power source?
I'm thinking of using a pair for a simple "dual mono" config, and I'm not sure how to power such a config... Would a single SMPS be OK, with a diode divider, perhaps?
Somehow it seems silly to put them in separate enclosures (monoblocks) with separate SMPS power bricks for each... as they are so tiny
Although, I guess that would be best for a pure stereo config, with each monoblock enclosure close to the speaker and short speaker wires...
Right now for testing purposes I am using a 24v SMPS brick. I just ordered a 24v 10amp SMPS for LED light strips.
https://www.amazon.com/gp/aw/d/B00QCJ9FAY/ref=ya_aw_od_pi?ie=UTF8&psc=1
There are many similar models by other manufacturers. Meanwell makes one too but is priced $41 vs $26.
You want me to measure R between the ends of the little red mark?
I have a bunch of nice Coilcrafts. Wonder if there is a way to rig them into that small space - maybe stretch the flat copper wire longer for a standoff?
If I want to measure amp THD like Dr Mord, Gmarsh, 5thelement, etc. is there a simple setup I can rig my external DAC/ADC with to do so and can REW be used for such a measurement ? What software do you guys use?
I have a basic UCA202 and am wondering if that an be called into service for an amp characterization system.
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On second thought, a SMPS brick with cord and 5amps may be more convenient and just using two will yield same performance and avoid 120vac wiring and dangers of open frame supplies. It costs a bit more but I think I will go this route instead.
https://www.amazon.com/gp/aw/d/B00LUIKY4S
https://www.amazon.com/gp/aw/d/B00LUIKY4S
The input caps are relatively exposed on the left side of the input pins so can be easily removed. I would stay with SMT to reduce stray field pickup. These amps are extremely quiet inherently. Maybe change 1uF to 4.7uF C0G? You could also just jumper the caps and have an outboard large scale ply film cap etc.
![s-l400[1].jpg](/community/data/attachments/474/474892-61e1824a97f231a2b235985bc092335a.jpg)
I ignored it. Can someone tell me how to use the mute pins if I wanted to? Just connect them together to mute?
I know you can find cheaper 0.47uF smd cog, but you get the picture when you look at this 0.47uF price and also check size (You said 4.7uF cog would be idea, you need lot of $$ and a larger pcb)
C2220H474J5GACTU Kemet | Capacitors | DigiKey
Maybe Wurths make inductors that fit, huge Coilcrafts are not likely to fit and may not be that good anyway.
(You said 4.7uF cog would be idea, you need lot of $$ and a larger pcb)C2220H474J5GACTU Kemet | Capacitors | DigiKey
Maybe Wurths make inductors that fit, huge Coilcrafts are not likely to fit and may not be that good anyway.
I guess I got that wrong, would X7R make it cheaper and smaller? I know I have seen 10uF caps that were not HUGE, maybe 3mm x 2mm. Voltage was probably lower but don't need that much for maybe 5v p-p on audio input so 15v may be just fine.
Since when does a single 0.47uF SMT cap cost $47? These are 5.7mm x 5.0mm. Who is going to $50 for a speck of cap?
Price is high because not in stock and they have to make a big run?
Since when does a single 0.47uF SMT cap cost $47? These are 5.7mm x 5.0mm. Who is going to $50 for a speck of cap?
Price is high because not in stock and they have to make a big run?
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It measures a short between the ends of the orange mark you made.
Across the cap it measures 121kohm.
Not sure if this helps.
You need a bit of voltage rating to keep dc-bias effects and distortion low. 25V is good, 50V is better. X7R is tested to be fine. (Like 1uF 50V 0805 from Murata, flex-soft terminals is nice to have)
Since we are talking about Sanwu boards. They make a 3116D2 wireless Bluetooth amp with speaker phone and play/pause and volume buttons for $13.
Online Shop Wireless Digital Bluetooth 4.0 TPA3116 50W+50W Audio Receiver Amplifier Board With Mic Free Shipping|Aliexpress Mobile
Online Shop Wireless Digital Bluetooth 4.0 TPA3116 50W+50W Audio Receiver Amplifier Board With Mic Free Shipping|Aliexpress Mobile
Mounting the inductors like that is art..
BT range is questionable due to antenna position. (Someone here in the forum had problems with this module)
I would like to have the buttons panelized on a second pcb. Internal mounting isn't possible like this.
Are you talking about how close the inductors are to the main chip on the Sanwu Blue PBTL? Or are you talking about custom mod to a Coilcraft or Wurth to get it to fit? I actually have some 4.5amp axial Bournes 10uH that could be used here I think.
I just ordered the BT Sanwu amp - I agree buttons on separate PCB would be way more convenient. You would need mechanical extension pushers or something to make this work. But hey $13 ? I won't complain. I can sort of understand how they sell $30 BT radios with buttons and speaker phone for $30 now.
Update on longer term listening to Sanwu Blue PBTL.
This amp sounds fantastic stock - perhaps one of the best stock amps I have heard. I am really enjoying them. Will continue to listen and in a few days connect to the miniDSP for a 4ch active system to drive my reference all horn loaded system to really hear what it can do.
One thing I am noting is that these amps are warm even when idling. The heatsink when sitting there with amps on and no music playing overnight feels warm maybe 15 deg F hotter than ambient. Not sure what makes them idle warm?
This amp sounds fantastic stock - perhaps one of the best stock amps I have heard. I am really enjoying them. Will continue to listen and in a few days connect to the miniDSP for a 4ch active system to drive my reference all horn loaded system to really hear what it can do.
One thing I am noting is that these amps are warm even when idling. The heatsink when sitting there with amps on and no music playing overnight feels warm maybe 15 deg F hotter than ambient. Not sure what makes them idle warm?