You just use a headphone splitter, like Belkin Rockstar or similar.
Given that the usual supported headphone minimum impedance is 16 ohm of almost any mp3 player or phone and that the typical input impedance of a TA202x amp is 22Kohm, any mp3 player's headphone output can effectively be split to (22000/16) 1375 TA202x based amps without the mp3 player seeing a more difficult load.
If you want an active solution something like a Behringer HA400 would do the trick.
You can even combine the two and use the Behringer to pull several of the Belkin Rockstars. That's 20 Boominators connected right away but limitless amounts is possible.
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Thanks for the replies, I'm not too far off then..... I hadn't thought of a headphone splitter but I still intend to build the throughput into the boominator......
we are planning a beach party in the summer and the boominator will be the main soundsystem and we will link up about 20 "minirigs" and an FM transmitter to it so that the signal can be picked up on radios over the whole coastline. I keep telling my minirig pals that they won't hear their minirigs over the boominator but they won't listen.... he he... can't wait to have the last laugh, for all the right reasons........
Tweeters on their way........
BJ
we are planning a beach party in the summer and the boominator will be the main soundsystem and we will link up about 20 "minirigs" and an FM transmitter to it so that the signal can be picked up on radios over the whole coastline. I keep telling my minirig pals that they won't hear their minirigs over the boominator but they won't listen.... he he... can't wait to have the last laugh, for all the right reasons........
Tweeters on their way........
BJ
Not sure if this should be asked here or on 41hz forums.
And I am Sorry if I'm rehashing anything, but a quick search didn't give a definative answer.
The Boominator in it's original design was for lower freq of 82Hz, and rolls of pretty quickly from there.
As you say 0.47uF is optimal, but looking at the calculation with the amp6 basic calculations ( assuming this is correct)
F=1(2*n*Rin*Cin)
So based on that the following should be correct Assuming the above is using the standard 22kohm resistors
0.47uF = 15hz
0.22uF = 33hz
0.15uF = 48hz
0.10uF = 72hz
so would not the ultimate Battery/Audio combo be 0.10uF low ESR caps, or is that too close to the roll off freq?
Q1. I might as well get the exact Capacitor now what would be the perfect size?
Q2. and could I get these from Jaycar?
Cheers, S.
Cheers, S.
Please look a few posts back where I explained it but the 0.47uF is the value.
It gives an x-o of 15hz and a roll-off that due to the low Q of the filter starts at 63hz. Even though the box Fb is 82hz the Fp (port tuning frequency) is 66hz. It is important that the Fp is unfiltered for optimum performance.
The input capacitor in itself is a feeble sub-cut filter but with the correct value it helps the built-in acoustic roll-off just enough. For greater effect I suggest a more advanced filtering.
Please get the exact replaced input capacitor suggested earlier in this thread or a similar compact size low voltage polyester or polypropylene capacitor. Large "audio grade" capacitors do not work well as input capacitors. Low ESR caps are especially unsuited for the task of input capacitors. Remember there's a 22Kohm resistor directly after it so the series resistance of any capacitor would be billions of times less than that anyways.
It gives an x-o of 15hz and a roll-off that due to the low Q of the filter starts at 63hz. Even though the box Fb is 82hz the Fp (port tuning frequency) is 66hz. It is important that the Fp is unfiltered for optimum performance.
The input capacitor in itself is a feeble sub-cut filter but with the correct value it helps the built-in acoustic roll-off just enough. For greater effect I suggest a more advanced filtering.
Please get the exact replaced input capacitor suggested earlier in this thread or a similar compact size low voltage polyester or polypropylene capacitor. Large "audio grade" capacitors do not work well as input capacitors. Low ESR caps are especially unsuited for the task of input capacitors. Remember there's a 22Kohm resistor directly after it so the series resistance of any capacitor would be billions of times less than that anyways.
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Yeah, that's all true!
The bad news:
I had an all afternoon long fight with my TA2020 over a reasonable input cap solution. The volume pot on one end and resistor on the other end made most capacitors that I had on hand. . . perform exactly like bad caps. After much effort, I ended up with a large composite mess that was unpleasant to build in such a tiny space, quite the eyesore, and works nicely. I did notice that the capacitance value had to be rather huge or else a) the tone changed with volume and/or b) bass blocker.
This amp behaves exactly like an inverting amp with the buffer omitted. For one passive part to replace several active parts is not simple but rather laborious. I hope that specifically recommended models of input cap are in the wiki???
The good news:
The spot for efficiency tuning worked much better with a cap in series with the woofer crossover. I simply found the smallest size cap that also couldn't interfere with the bass it could output. What I blocked is the workload of super-low bass the woofer couldn't output and now the amplifier will play twice as loud without clipping.
More bad news:
Then I added the ClipNipper circuit to the TA2020 so that when it did clip, it switched on a compressor so that clipping never reached the speaker. That worked okay until I tried battery power. Fail! My battery instantly "sank" to 9v and that wasn't compatible with my sensor.
More good news:
SO, instead of the compressor, what I really need to do is bi-amp. The tweeter-only amp won't clip, and that solves the audio quality problem easily.
The bad news:
I had an all afternoon long fight with my TA2020 over a reasonable input cap solution. The volume pot on one end and resistor on the other end made most capacitors that I had on hand. . . perform exactly like bad caps. After much effort, I ended up with a large composite mess that was unpleasant to build in such a tiny space, quite the eyesore, and works nicely. I did notice that the capacitance value had to be rather huge or else a) the tone changed with volume and/or b) bass blocker.
This amp behaves exactly like an inverting amp with the buffer omitted. For one passive part to replace several active parts is not simple but rather laborious. I hope that specifically recommended models of input cap are in the wiki???
The good news:
The spot for efficiency tuning worked much better with a cap in series with the woofer crossover. I simply found the smallest size cap that also couldn't interfere with the bass it could output. What I blocked is the workload of super-low bass the woofer couldn't output and now the amplifier will play twice as loud without clipping.
More bad news:
Then I added the ClipNipper circuit to the TA2020 so that when it did clip, it switched on a compressor so that clipping never reached the speaker. That worked okay until I tried battery power. Fail! My battery instantly "sank" to 9v and that wasn't compatible with my sensor.
More good news:
SO, instead of the compressor, what I really need to do is bi-amp. The tweeter-only amp won't clip, and that solves the audio quality problem easily.
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If your battery is dropping so much voltage, it sounds like you either need one with lower internal resistance, or perhaps some bulk capacitors with low ESR to take the transients.
The other thing I'm curious about is the addition of a capacitor in series with the woofer. Surely that'd interact with the twin peaks of the ported box alignment. Results would be interesting.
I'd expect it to lower current draw, due to increased resistance at LF, but (assuming a rigid supply) shouldn't alter when the amplifier clips.
I think I'd go for a 2nd order HP filter on the input board, set it to ~50Hz. I'm fairly sure that could make up part of the buffer, too. A single TL072 would do the job nicely for both channels.
There'd be virtually no current flowing with a 2nd order filter, so you'd be able to eliminate the large caps needed for speaker-level filtering.
Chris
The other thing I'm curious about is the addition of a capacitor in series with the woofer. Surely that'd interact with the twin peaks of the ported box alignment. Results would be interesting.
I'd expect it to lower current draw, due to increased resistance at LF, but (assuming a rigid supply) shouldn't alter when the amplifier clips.
I think I'd go for a 2nd order HP filter on the input board, set it to ~50Hz. I'm fairly sure that could make up part of the buffer, too. A single TL072 would do the job nicely for both channels.
There'd be virtually no current flowing with a 2nd order filter, so you'd be able to eliminate the large caps needed for speaker-level filtering.
Chris
HEhehe, as you all may or may not know, Easter holidays are upon me, and I thought I would do a mission to get my boominator in a configuration I can use for the camping trip tomorrow.
Using a crappy Lepai amp that I've have used before, as I haven't finished my Amp6 Basic's.
I have wired up for charging the batteries, and also wired up a usb adapter so I could keep my phone charged.
Closed everything up and took the unit outside.
Now to the right hand side of my house is a 'paddock' roughly 1/2 an acre, and placed the boominator a good 30 meters from the house accross the grass.
I powered it up and started playing some Led Zep remastered.
Volume about 30% I wandered around the unit a few times listening at different points , beer in hand... (mind you this is about 8pm, dark, no spot lights, after reading to the kids and the kitchen window open).
This was sounding quite good, so I crank up to %50, nodding my head and grinning with the unbelievable possibility that I put this thing together in the first place
I left the boominator out on the grass and wandered back to the house (this is a high set house with the top level with a wrap around veranda 4 meters off the ground, kitchen, dinning then lounge and bedrooms).
I got up to the veranda and it sounded clear as a bell! awesome..... then the wife comes out of the house...
"What the heck are you doing?... the kids are wondering what that noise is! and I can't hear the Television!"
test mission successfull!!! Ready for camping, but I think I may have to keep a restraint on the volume. lol
Solid Design Saturnus, Solid.
Cheers, S.
Using a crappy Lepai amp that I've have used before, as I haven't finished my Amp6 Basic's.
I have wired up for charging the batteries, and also wired up a usb adapter so I could keep my phone charged.
Closed everything up and took the unit outside.
Now to the right hand side of my house is a 'paddock' roughly 1/2 an acre, and placed the boominator a good 30 meters from the house accross the grass.
I powered it up and started playing some Led Zep remastered.
Volume about 30% I wandered around the unit a few times listening at different points , beer in hand... (mind you this is about 8pm, dark, no spot lights, after reading to the kids and the kitchen window open).
This was sounding quite good, so I crank up to %50, nodding my head and grinning with the unbelievable possibility that I put this thing together in the first place
I left the boominator out on the grass and wandered back to the house (this is a high set house with the top level with a wrap around veranda 4 meters off the ground, kitchen, dinning then lounge and bedrooms).
I got up to the veranda and it sounded clear as a bell! awesome..... then the wife comes out of the house...
"What the heck are you doing?... the kids are wondering what that noise is! and I can't hear the Television!"
test mission successfull!!! Ready for camping, but I think I may have to keep a restraint on the volume. lol
Solid Design Saturnus, Solid.
Cheers, S.
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Finally, music wins, television defeated. That's rare! Congrats!!
P.S.
I see so many stories of diy labors to create high quality audio systems for music, and these labors defeated by placing a television in the same room to silence the music. SO, it was wonderful to see an opposite story, where the music has won the battle. Thanks!
P.S.
I see so many stories of diy labors to create high quality audio systems for music, and these labors defeated by placing a television in the same room to silence the music. SO, it was wonderful to see an opposite story, where the music has won the battle. Thanks!
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I have used my boombox for at least 25-30 hours at moderate/comfortable listening levels and the LiFePo4 has been at 13.3 v for the last 20 hours. It hasn't even dropped a tenth of a volt.
Definitely won't use MDF again though. Way too brittle. Couldn't find a good source for other wood though.
Definitely won't use MDF again though. Way too brittle. Couldn't find a good source for other wood though.
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Finally started assembling my box and now it's time to fasten the woofers to the baffle!
Unfortunatly I ran out of silicone but I do have an opened tube of SuperSet - Casco , will most likely not be used before it gets to old anyway. Shouldn't be a problem using this instead ?
Also wondering if it necessary to fasten them with screws aswell ? Will the presure on each side och the speaker be enough will the glue and chemical metal settle?
Unfortunatly I ran out of silicone but I do have an opened tube of SuperSet - Casco , will most likely not be used before it gets to old anyway. Shouldn't be a problem using this instead ?
Also wondering if it necessary to fasten them with screws aswell ? Will the presure on each side och the speaker be enough will the glue and chemical metal settle?
The experience and proper equipment needed to surface mount nearly all the components on a 25 mm x 50 mm PCB.
Sound-wise they should be identical, as the Tripath TA2021B is just a repackaged TA2020A chip.
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