Here is my 4-channel Xmas amp made from a cardboard magnetic snap lid chocolate box.
That looks good.
Thanks! But I am afraid it doesn't sit well with the folks who think an amp should sit in a 60lb black anodized aluminum case with fins.
The box is actually covered in decorative aluminum foil that is electrically conductive - I had to remove certain parts not to cause a short. So there may be some shielding going on. The foil is connected to ground.
That's definitely an embargo thing. That's too bad because you mentioned how a lot of native Taiwan speaker companies were moving shop over to China. Then trade can't go from there to here. Highly asymmetric.
But we have a problem of being able to ever return ship anything from US to China. Due to asymmetric transportation of needing to fill the empty bellies of DHL airplanes returning from their perishable food deliveries to China, shipping from China is essentially free. Same package from US costs $15 to $80 to ship back. It sort of puts a diode on trade direction.
China trade
I've heard the opposite, at least as it pertains to container ships. I've heard that empty containers are shipped back to China to be re-filled with consumer goods to be sold in the US. If that's true, the cost to ship via boat to China is extremely low.
What you describe is probably correct, In my own business a Chinese vendor has recently started to provide "express" freight via air from China that is less expensive than slower container shipments.
I've heard the opposite, at least as it pertains to container ships. I've heard that empty containers are shipped back to China to be re-filled with consumer goods to be sold in the US. If that's true, the cost to ship via boat to China is extremely low.
What you describe is probably correct, In my own business a Chinese vendor has recently started to provide "express" freight via air from China that is less expensive than slower container shipments.
I wish one could use paypal for ali but paypal doesn't seem to do offshore purchases. Probably just a coincidence but my cc was recently compromised. The cc company must have a great algorithm as it nailed the problem and locked the account immediately with all fraudulent charges denied. Still an inconvenience as it took a week to get a new cc in hand.
Use a cc. Aliexpress works with a 3rd party credit card verification company that works with your bank - they have you verify the transactions the first few times and it is a pain at first to get an account all greased up and ready to go with Aliexpress. I had to buy a lot of small $5 and $10 amps, many of which the transactions got rejected over an over because of the security concerns. Once established though it is painless and I have not had any issues with security. Aliexpress sales via cc are also escrowed automatically. If you don't get your item in a certain time or if it is defective, the vendor does not get paid and you get a refund no questions asked.
How big is a practice amp? Like a 0.53x K'nator? A PA130-8 (50 watts nominal, 100 watts max) in a 0.53x Karlsonator would be a perfect pairing for the little 60w amp.
The PA130-8 also probably has the nice "guitar amp" sound too.
That full range is a pro audio driver designed for abuse. If you are worried, maybe put a line level -12dB/oct high pass filter at about 50Hz (a couple of tiny resistors and small caps). That will prevent over-excursion. But really, the 60watts won't kill the full PA130-8 in all likelyhood.
for a larger speaker, Cannabis Rex (12) was attractive sounding on guitar imo (and music) - PA130 may do well - there should be 6.5" for guitar to run off these little amps - - what's the highest power single polarity power supply amp module?
I don't know if the eight inch Eminator 1508 would be good for guitar but "maybe" - its resonance is right and so is the price at $15.50 delivered - two in parallel in a little open back cabinet might rock - what would one use for the preamp?
?
1508 ordering direct
Speaker Detail | Eminence Speaker
I don't know if the eight inch Eminator 1508 would be good for guitar but "maybe" - its resonance is right and so is the price at $15.50 delivered - two in parallel in a little open back cabinet might rock - what would one use for the preamp?
?
1508 ordering direct
Speaker Detail | Eminence Speaker
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hi X - do you think a 2092 would be good for a large boombox? - nice thing about say a TPA3116D2 would be the ability to truly be portable using a tool battery or bundled cells. How does the 7498 sound overall? do they come with an input plug/header? - the board I see seems to have a 3-pin input near its volume control. I also see a bluetooth version cheap - that could be great if it also has an aux input.
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The IRS2092's have a lot of power and are scalable in their design with selection of more powerful output stage mosfet's. They can be 1200w amps. They also have very low distortion figures. The downside is a requirement for dual rail power supply.
The TPA3116 can be battery powered that's for sure. The TDA7498's sound excellent and you are right - they have a 3pin header. The give you the 3pin connector with flying leads so you can connect to your source. I just take an old RCA cable and solder it directly to yen bottom of the board at where the 3 pins are.
The TPA3116 can be battery powered that's for sure. The TDA7498's sound excellent and you are right - they have a 3pin header. The give you the 3pin connector with flying leads so you can connect to your source. I just take an old RCA cable and solder it directly to yen bottom of the board at where the 3 pins are.
if I find a brick whose plug fits the board then will order some stuff - dunno what to do for a boombox - have neo mag 8" Fender 4ohm speakers, neo 8 ohm 10" P-Audio cx - do you know if the 7498 and 3116 bluetooth boards have switching between BT and aux? - the only BT transmitting device I have is an old laptop
here's a bluetooth version cheap http://www.ebay.com/itm/TDA7498-2-1...639152?hash=item25b3299e70:g:S1cAAOSwHPlWcOBL
here's a bluetooth version cheap http://www.ebay.com/itm/TDA7498-2-1...639152?hash=item25b3299e70:g:S1cAAOSwHPlWcOBL
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That's a nice board - I recently tested Sanwu boards and they sound excellent and are well made. Seeing that it has RCA inputs I would say it has a switch between BT and RCA inputs.
I might get that board myself. However I think that is a typo. That board has no BT visible from pictures. It looks like a great amp regardless though with switchable gain and volume knob and nice layout.
Here is a suitable 24v SMPS brick with correct connector.
http://www.amazon.com/gp/aw/d/B00LUIKY4S
This is a 3116 board with BT
http://m.aliexpress.com/item/32281628547.html?tracelog=storedetail2mobilesitedetail
I might get that board myself. However I think that is a typo. That board has no BT visible from pictures. It looks like a great amp regardless though with switchable gain and volume knob and nice layout.
Here is a suitable 24v SMPS brick with correct connector.
http://www.amazon.com/gp/aw/d/B00LUIKY4S
This is a 3116 board with BT
http://m.aliexpress.com/item/32281628547.html?tracelog=storedetail2mobilesitedetail
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I personally don't like those unshielded toroidal inductors. They are just asking to get knocked off with a bump. I like shielded inductors that are surface mount. Much sturdier and emit less RF.
These are the 7498's I use and they are excellent.
Online Shop TDA7498 100W+100W Class D Amplifier Board High Power Amplifier Board|Aliexpress Mobile
These are the 7498's I use and they are excellent.
Online Shop TDA7498 100W+100W Class D Amplifier Board High Power Amplifier Board|Aliexpress Mobile
same seller (I think -?) offers it on Ebay for a bit more TDA7498 100W 100W Class D Amplifier Board High Power Amplifier Board | eBay
also on Ebay shipped for $12.99 http://www.ebay.com/itm/New-TDA7498...174740?hash=item48666ead94:g:WXcAAOxyYANTcIW4
is the gain structure appropriate so it could be fed from the headphone jack of a cheap mp3 player without undue distortion?
there's that other version with 4 settings from ~21 to 33dB gain - would its heatsink be adequate at high levels?
http://www.ebay.com/itm/TDA7498-Cla...eea5d4d&pid=100005&rk=4&rkt=6&sd=131542224482
also on Ebay shipped for $12.99 http://www.ebay.com/itm/New-TDA7498...174740?hash=item48666ead94:g:WXcAAOxyYANTcIW4
is the gain structure appropriate so it could be fed from the headphone jack of a cheap mp3 player without undue distortion?
there's that other version with 4 settings from ~21 to 33dB gain - would its heatsink be adequate at high levels?
http://www.ebay.com/itm/TDA7498-Cla...eea5d4d&pid=100005&rk=4&rkt=6&sd=131542224482
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