Pop can well be solved by using the right input capacitor, but I am not going to further dig into that because this has already been discussed a million times....
All I can say is you should stay well away from the barrel sized high voltage junk.
Another way is to properly sequence the speaker relay, this doesn't really solve the pop, but just make it harmless....
http://www.youtube.com/watch?v=LhG9JjTRjJY
All I can say is you should stay well away from the barrel sized high voltage junk.
Another way is to properly sequence the speaker relay, this doesn't really solve the pop, but just make it harmless....
http://www.youtube.com/watch?v=LhG9JjTRjJY
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I thought that T1 & T2 from hifimediy have anti on/off pop included onboard already 😕
I've been reading quite a bit over here on last times, but only enaugh to let me decide to assemble my first diy amplifier (my electronics knowledge was 0 before that, and only a little bit more now, sorry)
Can you explain this: "All I can say is you should stay well away from the barrel sized high voltage junk."...
Hi, the t1 and t2 have anti pop relay's. Maybe something got damaged when you connected GND wrong.? can you hear the relays click now?
I'm sure relays click on power-on; I must check if they do it also on power-off (I was paying more attention to speaker pop, so I did not realize).
I will post it later when back home 😉
Hence my statement 'properly sequenced'.... The relays themselves don't prevent the pops, it's the timing/delay circuitry... (see my video)
The relays should click on later than the amp unmutes and click off before it mutes... The circuit on the breadoard there in my video can do that at a single flick of a switch. In the circuit that is attached it doesn't sequence a speaker relay though, but the SLEEP and MUTE pins directly. This doesn't always work well, but with a relay added it should be 100% fail safe....
The T1 and T2 boards should have pretty similar circuitry on the board, but I don't know these amps at all....
The relays should click on later than the amp unmutes and click off before it mutes... The circuit on the breadoard there in my video can do that at a single flick of a switch. In the circuit that is attached it doesn't sequence a speaker relay though, but the SLEEP and MUTE pins directly. This doesn't always work well, but with a relay added it should be 100% fail safe....
The T1 and T2 boards should have pretty similar circuitry on the board, but I don't know these amps at all....
Sorry to be so long replying, been gone for a while.
No, the Wurth coils on my T1 are no warmer than the heatsink nearby. The area between the output coils and the heatsink is the warmest on the board. I noticed this before the coils were changed and the trend has duplicated itself with the Wurth's.
I did run my T1 w/the Wurth's full range for a while before they were relegated to mid/tweeter duty and the coils were not noticeably warmer then, either.
No problems at all for me with this mod, all good.
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Thanks for the reply, it sounds like an interesting and relatively cheap experiment. I like the fact that the T1 runs significantly cooler than the T2(I have both) and would not want to add a lot of heat to the board. I may give the Wurth's a try and see if I can detect any improvement in an already good sound quality.
It's all a fight within the margin, want some big improvement get some BIG iron powder toroid inductors and see the idle current go down as well as the overall quality go up.
I can hear some tooth grinding going on:"But that is expensive!"....."But that won't fit on my board!"
Heck yeah!....
I can hear some tooth grinding going on:"But that is expensive!"....."But that won't fit on my board!"
Heck yeah!....
Hi,
I have a (probably stupid) question.
Is it possible to optimize the input sensitivity of the T2 board for iPod/iPhone devices?
The manual says:
Is there a simple workaround or do I have to use a preamp?
Thanks
I have a (probably stupid) question.
Is it possible to optimize the input sensitivity of the T2 board for iPod/iPhone devices?
The manual says:
Is there a simple workaround or do I have to use a preamp?
Thanks
Ever seen this??
http://www.datasheetcatalog.org/datasheet/Tripath/mXyzwqtx.pdf
It's all in there, and the answer is yes, you can change the sensitivity pretty easy by changing a few resistors.
There are tons of other resistor values on the board that actually NEED to be optimised for proper performance in your situation.
http://www.datasheetcatalog.org/datasheet/Tripath/mXyzwqtx.pdf
It's all in there, and the answer is yes, you can change the sensitivity pretty easy by changing a few resistors.
There are tons of other resistor values on the board that actually NEED to be optimised for proper performance in your situation.
Double gain
You can change R3/ R5 to 40k to double the gain in the front of the amp. Or, changing R1/ R4 to 10K will do the same thing.
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You can change R3/ R5 to 40k to double the gain in the front of the amp. Or, changing R1/ R4 to 10K will do the same thing.
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I would definitively NOT double the gain. This would create serious risks of damaging the amp!
eladmi : the amp will work well with an iphone. I used it with an HTC android phone for a while. You way not get full power out of the amp due to the limited output of a phone, but anyway who uses the full power given the distorsion at full level ?
you may :
1. just use it with the phone as source an be happy.
2. jaillbreak your phone to enable higher output level
3. use a preamp
4. go with T4 which has higher gain (and higher voltage power)
BTW, input sensivity of tc2000 is 1.5VRms
eladmi : the amp will work well with an iphone. I used it with an HTC android phone for a while. You way not get full power out of the amp due to the limited output of a phone, but anyway who uses the full power given the distorsion at full level ?
you may :
1. just use it with the phone as source an be happy.
2. jaillbreak your phone to enable higher output level
3. use a preamp
4. go with T4 which has higher gain (and higher voltage power)
BTW, input sensivity of tc2000 is 1.5VRms
Double gain no problem
The Sure 2X100 has switched input gain which can provide unity, +6db, or +9db in the input circuit as I have recommended. Many users choose to run +6db based on sound even if they can also achieve a loud listening level at unity. It is proven to work well. No problem. Just don't forget to turn the volume control down when changing sources. If you leave the volume control wide open and connect a loud source, you can blow the amp regardless if you mod the input or not.
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The Sure 2X100 has switched input gain which can provide unity, +6db, or +9db in the input circuit as I have recommended. Many users choose to run +6db based on sound even if they can also achieve a loud listening level at unity. It is proven to work well. No problem. Just don't forget to turn the volume control down when changing sources. If you leave the volume control wide open and connect a loud source, you can blow the amp regardless if you mod the input or not.
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Nonsense, this won't by far damage the amp!!
The 20K/20K gain setting is pretty standard and you can freely triple or quadruple the gain with still barely risk of damaging the inputs.
Off course best thing is to measure (or loop up) the output level of the phone/MP3 player and then calculate the correct gain level to make the output swing to the full voltage.
You can also use step-up audio transformers to increase the level.
You can off course add a preamp, but this is the least easy way t achieve higher output.
If you are scared to damage the inputs you can always use diodes to clamp the inputs to max 5Vpp. This is a pretty simple circuit to add which ensures the input can not be overdriven...
The 20K/20K gain setting is pretty standard and you can freely triple or quadruple the gain with still barely risk of damaging the inputs.
Off course best thing is to measure (or loop up) the output level of the phone/MP3 player and then calculate the correct gain level to make the output swing to the full voltage.
You can also use step-up audio transformers to increase the level.
You can off course add a preamp, but this is the least easy way t achieve higher output.
If you are scared to damage the inputs you can always use diodes to clamp the inputs to max 5Vpp. This is a pretty simple circuit to add which ensures the input can not be overdriven...
Thanks for all the replies. So changeing r3 and r4 to 20 k would do the trick? I am not good at smd soldering though.
R3/ R5
That would be R3/ R5 according to the schematic and it shows they are already 20k. If R1/R4 are indeed 20k then change R3/ R5 to 40k to double the gain and sensitivity to improve the use with Ipods. The schematic is posted here.
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http://hifimediy.com/wp-content/uploads/2010/11/T2-100W+100W-classT-amplifier.pdf
That would be R3/ R5 according to the schematic and it shows they are already 20k. If R1/R4 are indeed 20k then change R3/ R5 to 40k to double the gain and sensitivity to improve the use with Ipods. The schematic is posted here.
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http://hifimediy.com/wp-content/uploads/2010/11/T2-100W+100W-classT-amplifier.pdf
for information
Highest Voltage Output (source : http://beavishifi.com/articles/headphonejack/)
The gain V/V of the amp is (for the right channel) :
R5/R4 * (R15 + R11) / R11
to increase gain, increase R5 or lower R4 ?
SURE seems to lower R4 on their board. They add 22K resistors (0,1,2 depending on switch) in parallel to the existing 22K input resistor on their board.
I would suggest you do the same : if you want to double gain V/V, solder a 20K resistor in parallel to existing R4. And to R1 for left channel.
Highest Voltage Output (source : http://beavishifi.com/articles/headphonejack/)
an Ipod output is 1Vrms where a typical consumer audio device is 2Vrms
The gain V/V of the amp is (for the right channel) :
R5/R4 * (R15 + R11) / R11
to increase gain, increase R5 or lower R4 ?
SURE seems to lower R4 on their board. They add 22K resistors (0,1,2 depending on switch) in parallel to the existing 22K input resistor on their board.
I would suggest you do the same : if you want to double gain V/V, solder a 20K resistor in parallel to existing R4. And to R1 for left channel.
Either way
Either way works the same. I prefer higher than 20K values for both resistors based on listening even though I run 1:1
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Either way works the same. I prefer higher than 20K values for both resistors based on listening even though I run 1:1
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