To the power ground
It is used (series) for one of the tweeter wires, thus achieving SE mode for the tweeter.
Here it is: Set a tweeter on top of your speaker. Run a single conductor wire from that new cap, over to one terminal of the added tweeter. Connect the other terminal of that added tweeter to one of your speaker's jacks.
The woofer would be hooked up same as you already have now.
The added tweeter uses only one of the speaker terminals.
A bridge chip already has 2 amplifiers inside the chip, so you don't need to buy more.
Oh, put down the saw?
I wasn't suggesting building a new speaker.
What I was suggesting was adding a tweeter, set easily on top of the speaker that you already have. Since it is doing only high frequencies, it be called a super-tweeter. And, on top of the box is the typical location for it.
Preferably, it would be a rising response type, like a 3/4" metal dome or any electrostatic/panel/ribbon type. SE mode use is cleaner but quieter, so our added tweeter would need to be approximately 6db more efficient (however, it will probably work just fine even if it isn't any more efficient than the main speaker).
Face-up mounting of a tweeter is only for use when there is more than one tweeter. It is also seen with full range, the Ambiance model over at commensenseaudio.com with the Audio Nirvana full range drivers (one of the 8" has a rising HF response suited to face-up use). That cabinet is actually their favorite design. Although our super-tweeter application won't do a bass boost too, it will probably get the ambiance job done just as well, despite the cost difference.
Added "super-tweeter" run in SE mode does two jobs. You get the cleaner (higher resolution) but quieter output of SE mode. And, face-up super-tweeter serves more than a single central chair, so more than one person will be able to hear in stereo, with imaging audible in most areas of the room. Most of us are not living with ideal test conditions for speakers (a padded room with only one chair); so, the rest of us might find broader dispersion useful. My living room happens to have the speakers positioned to suit the furniture arrangement, not the audio. And, reviews for speakers seem to never review such typical real-life usage conditions. But, if they had, I think we'd find a lot of the Ambience, face-up super-tweeter, Ohm Walsh styles and 360 degree tweeters commonplace. Oh well. For those living rooms with more than one chair, we can DIY the solution rather easily (one little cap, a one-conductor wire, and an added tweeter). We also need clean signal for it, and that's available in SE mode.
Problem:
Face-up super-tweeter sometimes won't play higher than 10k. That will happen if it isn't both efficient and rising response. The fix is to suspend a 1.2" (or so) metal object about an inch (the height of an orange wirenut) over top of the tweeter. I cautiously cut a 4 bladed fan shape (with the blades well bent--not a flat disc) out of the bottom of a soda can to use for this. However ball and cone/funnel shapes can also work. The small HF reflector will extend the range to 16k. If you've chosen a cloth dome tweeter, then you might need the reflector. And, if that dome tweeter happens to be the type that has this black plastic "bridge" over top of the dome, then you can park an actual orange wirenut on there, to hold up the reflector.
It won't quite outperform an electrostatic/panel/ribbon type (which are already rising response and probably won't need the HF reflector), but I just mentioned this in case there's an extra tweeter in your parts box (free) that probably could be doing a useful job.
If the face-up super-tweeter isn't working for you to hear the ambient cues, then you can try angling up the tweeter. The functional range is 45 degrees to 90 degrees separation from the face of the speaker.
At less than 45 degrees there is risk of comb filtering (sounds like static) unless your speaker's existing tweeter is dull or you install extra crossover parts to cause that, in which case you've now got a 3 way speaker and your super-tweeter can be mounted on the front panel.
See also Ohm Walsh speakers, which have 360 degree super-tweeter on top.
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Thanks ,lot to digest. I have shipped the powered speakers over to the grandsons bedroom 35 miles away. I can build anything I want, especially wood. His speakers were 8" balls I made from paper mache and fg resin to finish. Came out great. I will try your suggestion when 3 other projects get finished. Building my first mini amp, the mini cmoy from audeoangelica, a PVC Bluetooth speaker with 3.5 BMR's on each end and the little 2"s for the tweeters using tpa3116 w bt module, and an old school 2.5 way with 2 hivi 3" and a passive sub using dual mono tpa3118. I have some mcm55_1853 and soft dome tweeters FIFA I think, also have some cheap horn tweeters with more sensitivity might work on top up firing? The mcm and FIFA are extra from zaph buyer minis
Ok thanks for the detailed advice Dan! I like ambience! Candles, miles Davis, beautiful woman.....have a few other projects to finish up and will get started on this next, interesting concept. I have to build new speakers because my previous 8932 kit is long gone to the grandson! A bit bass accentuated but hey he is 9 and they dig bass!
If you use a standard 2nd order parallel crossover, you could simply split the crossover (bass section and separate treble section) to arrange for bi-amp.
However, if the amplifiers are different (or mixed mode), you might want a dial to adjust the tweeter output level.
Might also want 4 conductor speaker jack (in case of bi-amp with two different amplifiers).
However, if the amplifiers are different (or mixed mode), you might want a dial to adjust the tweeter output level.
Might also want 4 conductor speaker jack (in case of bi-amp with two different amplifiers).
This thing definitely wins on value if nothing else. I still find some "charm" to these little boards that I can't put my finger on. A few posts back I showed my messy no-case implementation. Yesterday I moved everything into a $20 case. Ultra compact, cheap, great sound.
I thought maybe those Sanwu boards would accept differential input, hence the XLR sockets. Of course I didn't test this before I put everything in a case. 🙂 I found when feeding the board a differential input, I got tons of hum. Shorting the cold input to ground completely eliminates that. So now my amp uses XLR sockets for single-ended input. Oh well. Still sounds fantastic.
I have too many projects in the queue right now, but I'd like to design a PCB for this chip. I think I'd clone the Sanwu design, except: bigger/beefier inductors, balanced input, bigger power supply decoupling caps, and bigger solder holes for the screw terminals.
I thought maybe those Sanwu boards would accept differential input, hence the XLR sockets. Of course I didn't test this before I put everything in a case. 🙂 I found when feeding the board a differential input, I got tons of hum. Shorting the cold input to ground completely eliminates that. So now my amp uses XLR sockets for single-ended input. Oh well. Still sounds fantastic.
I have too many projects in the queue right now, but I'd like to design a PCB for this chip. I think I'd clone the Sanwu design, except: bigger/beefier inductors, balanced input, bigger power supply decoupling caps, and bigger solder holes for the screw terminals.
Attachments
I agree!
Fun on the cheap! Nice compact layout in that case. Do you have a link to your power supply? I have been using AC to DC power cords I purchased at a thrift shop for $1.00. Do u think it would make a significant difference using your PS vs mine? I think I mostly use 12V 3 or 5 amp, and 19V 4 amp bricks? I put them in all kinds of small chassis, like little wood jewelry boxes all decorated up for the grand kids. Can go real small without ps in the case.
Fun on the cheap! Nice compact layout in that case. Do you have a link to your power supply? I have been using AC to DC power cords I purchased at a thrift shop for $1.00. Do u think it would make a significant difference using your PS vs mine? I think I mostly use 12V 3 or 5 amp, and 19V 4 amp bricks? I put them in all kinds of small chassis, like little wood jewelry boxes all decorated up for the grand kids. Can go real small without ps in the case.
How are these Sanwu TDA8932 boards compared to the Sanwu TPA3118 boards (which I use in combination with a very good 24V linear power supply)? Is the character of the sound different? I hope someone can tell me!
Different
Yes quite different. If you go back and read Daniels original post he does a very good job of trying to describe the sound difference. Less fatiguing, more open, deeper bass, less treble and less definition comes to mind? I like them all, bigger sounding and less defined is how I would sum it up. Daniel gives a little tweak to try and get more def in the highs. I haven't tried yet. Just installed alpine HU and 150 watt sub amp in my van and nearly come out of it with my yolk cooked solid. It's 96 deg in the shade with high humid in central Florida! My workshop is in the unairconditioned garage, ugh!
Yes quite different. If you go back and read Daniels original post he does a very good job of trying to describe the sound difference. Less fatiguing, more open, deeper bass, less treble and less definition comes to mind? I like them all, bigger sounding and less defined is how I would sum it up. Daniel gives a little tweak to try and get more def in the highs. I haven't tried yet. Just installed alpine HU and 150 watt sub amp in my van and nearly come out of it with my yolk cooked solid. It's 96 deg in the shade with high humid in central Florida! My workshop is in the unairconditioned garage, ugh!
sailmanbigd, here is a link to the power supply:
AC110V 220V to 24V DC 9A 150W Industrial Power Switching Supply Converter Module | eBay
I bought a couple of these. I have tested them to 6 amps output. Don't know if they will actually make it to 9 amps though.
AC110V 220V to 24V DC 9A 150W Industrial Power Switching Supply Converter Module | eBay
I bought a couple of these. I have tested them to 6 amps output. Don't know if they will actually make it to 9 amps though.
I've not tried different power supplies with the tda8932 amps.
With the tpa311x amps, my favorite power supply is the Connex SMPS300R. But I haven't tried the power supply in my picture with the tpa311x amps.
Here's one ebay link for that power supply. Note there is at least one variation on it. I have two of these, the model number appears to be WX-DC2416.
They are $11 shipped! Then I spent another $10 or so to upgrade the caps with these:
primary cap: United Chemi-Con KXG EKXG251ELL221MMN3S (220 uF / 250 VDC), mouser part number: 661-EKXG251ELL221MMN
secondary caps - bulk: United Chemi-Con KYB EKYB350ELL102MJ30S (1000 uF / 35 VDC), mouser part number: 661-EKYB350E102MJ30S
And then I put a couple of these directly across the output +/GND terminals:
secondary caps - filter: TDK X7R 10% 1206 C3216X7R1V106K160AC (10 uF / 35 VDC), mouser part number: 810-C3216X7R1V106KAC
That listing is either confused or dishonest. The title is wrong, but the description is accurate. That supply is 4A continuous 6A peak. There is a similar, slightly taller, slightly more expensive version that is 6A continuous / 9A peak. In fact, the same seller stocks it.
Confusing
Yes, thanks for the links. I did see in title line 9A, then in description 4-6A and 5A in the pics! I think maybe a language issue? So, anyone able to speak of the difference in sound quality/quantity using these power boards vs the box in the cord ones I have been using? I think some were from computer/laptop supplies? Thanks again for the links
Yes, thanks for the links. I did see in title line 9A, then in description 4-6A and 5A in the pics! I think maybe a language issue? So, anyone able to speak of the difference in sound quality/quantity using these power boards vs the box in the cord ones I have been using? I think some were from computer/laptop supplies? Thanks again for the links
I think it was probably just clumsy content management when reusing the description for two similar modules.
Add me to this chip amp thing. Been on the fence for a long time and finally pulled the trigger. $2.63 shipped (I upgraded to faster for another $2.50) Just over $20 for 7 modules shipped.
I have a 3 way high eff all horn setup and plan to implement 3 way active XO via Behringer 2496 and run 6 of these modules. Still a little fuzzy on conversion to SE mode and printed out chip data and studying. I am no EE but no novice and I can see what would be done to chip but unsure how with the board. Will be fun to play around.
I have a 3 way high eff all horn setup and plan to implement 3 way active XO via Behringer 2496 and run 6 of these modules. Still a little fuzzy on conversion to SE mode and printed out chip data and studying. I am no EE but no novice and I can see what would be done to chip but unsure how with the board. Will be fun to play around.
I tried searching the thread for 3118 comparisson, but found nothing useful. So:
I currently run 3118 sanwu mono boards (gain reduced to 20db) to Mark Audio CHR70. Do I gain or lose anything if I buy these https://www.aliexpress.com/item/Fre..._3&btsid=dcc2d8d3-64cf-4e15-bc46-00ea727f6ca3 instead?
I currently run 3118 sanwu mono boards (gain reduced to 20db) to Mark Audio CHR70. Do I gain or lose anything if I buy these https://www.aliexpress.com/item/Fre..._3&btsid=dcc2d8d3-64cf-4e15-bc46-00ea727f6ca3 instead?
Some of the Class D is really entertaining. . .
I just made two purchases.
1). TDA8932 Bluetooth Stereo board. Stereo with just one chip also means SE mode. The filter caps look small; but, they're through-hole so that isn't difficult. Also, I put the Onkyo app on the phone, for the bluetooth hi-fi.
2). That little 6a SMPS board. Sure it was only $1 cheaper than the 10a version; however, the 6a version didn't annoy me with a photo of three electrolytic caps pressed up against a heatsink for a fast demo of incompetence like the 10a version. So I bought the nice looking 6a version. Looks like it probably works. And that other thing didn't.
Also, 43% of the 6a capacity is enough for 2x channels in SE (stereo) mode without assuring dirty power. Well, I do have 8 ohm speakers. So, the loading is evidently within the clean capacity of the 6a SMPS even if I improve the caps on the amp board, as planned.
Well, this looked like a good idea, so I bought them. You know I won't hesitate to either complain or praise as needed (possibly both).
Let's see what happens.
I am suspicious that it will be great.
I just made two purchases.
1). TDA8932 Bluetooth Stereo board. Stereo with just one chip also means SE mode. The filter caps look small; but, they're through-hole so that isn't difficult. Also, I put the Onkyo app on the phone, for the bluetooth hi-fi.
2). That little 6a SMPS board. Sure it was only $1 cheaper than the 10a version; however, the 6a version didn't annoy me with a photo of three electrolytic caps pressed up against a heatsink for a fast demo of incompetence like the 10a version. So I bought the nice looking 6a version. Looks like it probably works. And that other thing didn't.
Also, 43% of the 6a capacity is enough for 2x channels in SE (stereo) mode without assuring dirty power. Well, I do have 8 ohm speakers. So, the loading is evidently within the clean capacity of the 6a SMPS even if I improve the caps on the amp board, as planned.
Well, this looked like a good idea, so I bought them. You know I won't hesitate to either complain or praise as needed (possibly both).
Let's see what happens.
I am suspicious that it will be great.
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Yes.
I searched for TDA8932 Stereo
And then I bought it.
Link:
TDA8932 Bluetooth Stereo Digital Amplifier Board Speaker 2X15W for 12V 24V Car | eBay
Looks like there might be a caveat solvable by easy through-hole soldering.
It is in the mail.
Definitely let us know how it sounds. I looked at them but thought it was too expensive considering the price of other amps.