Sure Electronics New Tripath Board tc2000+tp2050

[kristleifur]

Originally Posted by Drakmin

Hi,

Can I set the input sensitivity to high without the fear of breaking anything with Ipod and cellphones as audio source? I'll be using the amp with 18,5V battery in a ghettoblaster. How much power do I get with 18,5V for 4 ohm load?

Is it safe to use only one output channel and just convert input signal to mono since my blaster is a mono design.

Thanks!

Speaking from my experience with 41Hz Amp4 / Amp11 that use the same chipset - they can't be too different:

1) You can set the gain pretty high. I have mine at 50 / 22 = ~2.3 X voltage gain in input stage. No problems. People have used 80 / 22 gain resistor ratios successfully. Besides that, I have my rail-voltage "power gain" resistors set a little too hot for the power I'm feeding my amps, and still everything is running very happily. If you set the input gain too high and feed a hot signal, you'll get an input-overload warning logic signal from the chip, that probably feeds a little LED that will crunch on. If you come too close to the power rails with the power stage gain, you'll get some crunch and distortion.

Too high gain costs some noise of course. But you won't destroy anything.

2) You'll be getting just under 40W max.

3) Mono? Yep. You can either zero the extra channel, or parallel them both into the same load.

You could check the 41Hz forums also for some more background on these issues - they're pretty commonly discussed there.

[chaos_maniac]

Oh, I'm sorry. It seems my toroid inductors are material 52, it was hard to see the blue because of the black coat on the coils. Will this pose a problem in the TK2050 or TA2020? Permeability = 75 according to: iron powder material properties

I see most of you use coils with permeability = 10 or less, will 75 cause serious issues then?

[sendler]

Originally Posted by ChuckT

Hi sendler,

a question about the coil, if such a low value 3.5uH is used for those tiny hi perm shield coil, than perhaps the same low value on those high quality high perm coil would give even better result. eg. MPP core with 125 perm.

I think I am done with coils. Done with amps! Done with my source (modified DCX2496). Time now to move on to the speakers. Active cross, constant directivity, dipole array, 4 way.

[kristleifur]

Originally Posted by sendler

I think I am done with coils. Done with amps! Done with my source (modified DCX2496). Time now to move on to the speakers. Active cross, constant directivity, dipole array, 4 way.

Impressive and interesting. Please keep us posted.

[chaos_maniac]

Originally Posted by chaos_maniac

Oh, I'm sorry. It seems my toroid inductors are material 52, it was hard to see the blue because of the black coat on the coils. Will this pose a problem in the TK2050 or TA2020? Permeability = 75 according to: iron powder material properties

I see most of you use coils with permeability = 10 or less, will 75 cause serious issues then?

I couldn't wait for an answer, sorry. I just put the 52 material 10uH coils into my Lepai TA2020, it seems to work - though I haven't been able to properly test it. If it works fine without any ringing etc. these toroids are going on my Sure TK2050 board as well.

[Drakmin]

So this is a safe way to get a mono output and not to lose another channel?

[kristleifur]

Originally Posted by Drakmin

So this is a safe way to get a mono output and not to lose another channel?

Ah, you can't feed it a stereo signal - each channel must be fed the same signal. You can do it by simply wiring inputs 1 and 2 together.

If I understand the picture like it's meant to be understood, the amp is trying to feed a stereo signal into a mono load. The mono load is fine, but the signal must also be mono, and identical.

[sendler]

Originally Posted by Drakmin

So this is a safe way to get a mono output and not to lose another channel?

I don't think you can just parallel the outputs. The differing DC offsets will be a problem and you would also need some .22ohm output resistors on each leg to keep one channel from current hogging and it still might fry something. Not sure. I probably won't be the first to try it.

[sendler]

Originally Posted by chaos_maniac

I couldn't wait for an answer, sorry. I just put the 52 material 10uH coils into my Lepai TA2020, it seems to work - though I haven't been able to properly test it. If it works fine without any ringing etc. these toroids are going on my Sure TK2050 board as well.

The perm value doesn't prevent you from using a coil as long as the windings and core have enough current rating to avoid saturation. These amps are only mid powered so it would take a really small core to cause a real failure in the event of a short circuit at the speaker wires.

[kristleifur]

Originally Posted by sendler

I don't think you can just parallel the outputs. The differing DC offsets will be a problem and you would also need some .22ohm output resistors on each leg to keep one channel from current hogging and it still might fry something. Not sure. I probably won't be the first to try it.

OK I'll back this up somewhat: DC offsets must certainly be 0.

Paralleling any Tripath amp is generally possible, AFAIK!, as long as you observe the current limits and watch the temperature. But it's not explicitly supported in all cases ...