Hi.I built them many years ago and they were waiting for a good toroidal transformer.Now i found them and see there is 2 power supply connecting points in both left and right side.I checked by multimeter and see they are parallelled.Why is it like that? Where should i connect them? Is it for preventing from GND loop?
TDA7294 × 3
DCV +28 0 -28 8a
4700uF 35V × 4 nichicon
60Hz 80Hz 100Hz 3rd order Sallen-Key Low-pass Filter
Load 3.6 Ohm Subwoofer
TDA7294 Cool IC no heat
Preamp shunt regulator
test with infinity reference 12inch Subwoofer nice bass performance
DCV +28 0 -28 8a
4700uF 35V × 4 nichicon
60Hz 80Hz 100Hz 3rd order Sallen-Key Low-pass Filter
Load 3.6 Ohm Subwoofer
TDA7294 Cool IC no heat
Preamp shunt regulator
test with infinity reference 12inch Subwoofer nice bass performance
PA150 Shine7 style, 3x LM3886, stereo set, recycled computer case, fan controller circuit by Giorgos Lazaridis (PCB by Alex mm), heatsinks from Compaq computer, laser-cut acrylic back panel.
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The image is not clear, but the heatsinks are pretty much like this one.
Are you doing three LM3886 per channel? How is that done? I only have 1 per channel, but I'm guessing yours isn't bridged?
Not bridged, but paralleled ICs.
More information on paralleling LM3886's here:
https://www.ti.com/lit/an/snaa021b/snaa021b.pdf?ts=1683833529891
They go down to 3 ohms loads.
Further reading here:
https://www.diyaudio.com/community/threads/pcb-3xlm3886-pa150-150w.215211/
More information on paralleling LM3886's here:
https://www.ti.com/lit/an/snaa021b/snaa021b.pdf?ts=1683833529891
They go down to 3 ohms loads.
Further reading here:
https://www.diyaudio.com/community/threads/pcb-3xlm3886-pa150-150w.215211/
Is Perter still around?
I have been e-mailing him and no response and no resonse on this forum either
I have been e-mailing him and no response and no resonse on this forum either
Hi.
Did not find any thread to post boomboxes, maybe it should be created, so all could share builds in one plavce, just like all mayor speaker types have their own threads 🤔
Anyways,
This is my portable speaker, built to look different. I like Mad Max, rat rod car culture, apocalypse theme.
Found this box from some instrumentation, had some speakers lying around. Never made something look rough on purpose, so decided to try it. It was huge fun. Boombox is used a lot and improved little by little by adding features, and things like some bars to protect woofers from damage. I love this boombox, sounds good enough, has adequate bass. And it looks good next to my tractor with similar style 😀
Key specs, used parts:
I call it APO (apocalypse)
Dayton ND16FA-6 tweeters,
Visaton FR10 as woofers (4"),
TPA3110 amp for tweeters,
TPA3116 amp for woofers,
ADAU1701 DSP for crossovers, EQ and tone controls,
4S 16.8V 5Ah (21700 sized cells) lithium battery, 30+hrs normal volume,
Charge port for normal 16.8V charger brick,
USB C charge port with QC support, so I can charge it with phone chargers,
Gauge on top shows state of charge, nor in real percent, but voltage based, may upgrade circuit to show real percent.
For now 3.5mm jack only, APTX HD bluetooth module ordered.
Two knobs for bass and treble.
Did not find any thread to post boomboxes, maybe it should be created, so all could share builds in one plavce, just like all mayor speaker types have their own threads 🤔
Anyways,
This is my portable speaker, built to look different. I like Mad Max, rat rod car culture, apocalypse theme.
Found this box from some instrumentation, had some speakers lying around. Never made something look rough on purpose, so decided to try it. It was huge fun. Boombox is used a lot and improved little by little by adding features, and things like some bars to protect woofers from damage. I love this boombox, sounds good enough, has adequate bass. And it looks good next to my tractor with similar style 😀
Key specs, used parts:
I call it APO (apocalypse)
Dayton ND16FA-6 tweeters,
Visaton FR10 as woofers (4"),
TPA3110 amp for tweeters,
TPA3116 amp for woofers,
ADAU1701 DSP for crossovers, EQ and tone controls,
4S 16.8V 5Ah (21700 sized cells) lithium battery, 30+hrs normal volume,
Charge port for normal 16.8V charger brick,
USB C charge port with QC support, so I can charge it with phone chargers,
Gauge on top shows state of charge, nor in real percent, but voltage based, may upgrade circuit to show real percent.
For now 3.5mm jack only, APTX HD bluetooth module ordered.
Two knobs for bass and treble.
TDA2004 chipamp converted to current drive put into a plastic box for electric installation.
With 15v, 2a wall wart.
https://www.diyaudio.com/community/...fication-to-current-drive.389985/post-7374638
With 15v, 2a wall wart.
https://www.diyaudio.com/community/...fication-to-current-drive.389985/post-7374638
Attachments
Don't laugh, guys. We all have to start somewhere! Here's my first DIY amp - LM386 on a costco coffee lid. Yes, I know the soldering is wonky 😴
I plan to do an LM1875 next.
I plan to do an LM1875 next.
Chipamp just lift off from the kitchen table:
OPA 549, 2x 100VA trafo ; +-25V DC; 22 000uf per rail. Non Inverting config, thanks forum member Alcaid for PCB layout.
Enclosure aluminium top cover still need polishing and M6 100mm screws (ordered).
In addition to the wooden enclosure came eight meat boards 😀
Sounds nice, no hum - i will compare it with my LM3875 NI and take some measurements with scope and sound-card tomorrow.
Hi @osscar , I'm curious which power switch you used for that amp. I really love the yellow.
