Sure Tk2050 4x100 really quiet

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I'm a little confused on this. The Sure site states the input sensitivity as 0.771 V. That is the required input voltage to drive it to full output and most home audio equipment should put that out. Is the issue the input impedance of 22 K? If driven by a device with a high output impedance the amps input could be loading that down too much so that the input voltage actually drops.What are you driving the amp with?

If the above is correct then the gain of the amp is not the issue, but the somewhat high input impedance. If that is the case then a buffer with very high output impedance might be required.

Rod
 
It's being run off an M-audio audiophile USB from my pc. With the PC turned up to full and the m-audio turned up to full running some bose 4 ohm pc style speakers I'm getting a fairly normal listening volume, definitely by no means loud.

I asked sure the same question and their response was that I needed a 400w power supply, amazes me how clueless they are there, I'm definitely getting NO WHERE near 100w a channel out of it, my old 20wpc @ 4 ohm went much much louder.

Can't find the output impedance of the m-audio anywhere :(
 
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If the above is correct then the gain of the amp is not the issue, but the somewhat high input impedance. If that is the case then a buffer with very high output impedance might be required.

Rod

I misspoke - Should have said "If the above is correct then the gain of the amp is not the issue, but the somewhat LOW input impedance. If that is the case then a buffer with very LOW output impedance might be required.


Rod
 
quick bump to this as I don't want to start another thread.

My version isn't a shure, is an ebay thing claiming to use a TK2050 but it isn't as loud as it should be.

setup is a 12 volt battery going to a voltage booster outputting 30 volts

the odd thing is I can turn it up to full volume (on the MP3 player putting sound into it) and adjust the input voltage from 12 to 30 volts and there is no discernible change in volume, wtf? might try burning it in for a while.
 
quick bump to this as I don't want to start another thread.

My version isn't a shure, is an ebay thing claiming to use a TK2050 but it isn't as loud as it should be.

QUOTE]

I think the Sure versions have a set of dip switches for setting gain. Any on your amp?

the odd thing is I can turn it up to full volume (on the MP3 player putting sound into it) and adjust the input voltage from 12 to 30 volts and there is no discernible change in volume, wtf? might try burning it in for a while.

Increasing the rail supply will only increase headroom to accommodate higher output. It will not change the overall gain.

I working with a TPA3116 eBay amp now. I can drive it to full volume with line out on my PC but can't get anything useful with my mp3 player as its output is much lower.

My solution was easy, the Sure headphone amp for ~$8. it provided the necessary boost (selectable gain of 9 or 15 dB). Now mp3 players drives the TPA3116 to full volume. The beauty of this was that I'm running the amp at 24v and the Sure headphone amp will also run at 24V as well. So all on I needed was a tap on the power and 1 additional signal cable.

If your running your amp at 30v, you would have to step that down to 24V or less for the Sure headphone amp (or just tap the 12V before the up converter - the Sure will run fine of 12v).
 
Thanks for the reply Mike, much appreciated.

I think the Sure versions have a set of dip switches for setting gain. Any on your amp?

none that I could find, there are two potentiometers but I worked out they are for adjusting DC offset.

Increasing the rail supply will only increase headroom to accommodate higher output. It will not change the overall gain.

I working with a TPA3116 eBay amp now. I can drive it to full volume with line out on my PC but can't get anything useful with my mp3 player as its output is much lower.

My solution was easy, the Sure headphone amp for ~$8. it provided the necessary boost (selectable gain of 9 or 15 dB). Now mp3 players drives the TPA3116 to full volume. The beauty of this was that I'm running the amp at 24v and the Sure headphone amp will also run at 24V as well. So all on I needed was a tap on the power and 1 additional signal cable.

If your running your amp at 30v, you would have to step that down to 24V or less for the Sure headphone amp (or just tap the 12V before the up converter - the Sure will run fine of 12v).

That makes sense I guess, a pre-amp would be ideal as having to use the volume control on the MP3/whatever player is annoying. I have one of these (or a clone of it) based on a TA2024 and it seems just as loud and a bit less noisy, probably has a rudimentary preamp of some kind.

Dayton Audio DTA-2 Class T Digital Audio Amplifier Module

Do you have a link to the headphone amp you used? I'm sure 24 volts will give all the juice I need, but can easily tap into the 12 volt side if that will work.

I'll hook up my PC or something else to confirm it will work as I expect, then buy more bits to make it work.
 
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oops, looks like Sure is a brand as well as Shure, that's my thing learned for today.

also thanks for the tip on the TPA3116, there are some variants which are very relevant to my interests!

Here's a link to the Sure pre-amp.

Sure Electronics AA-AB32261 Stereo 2 x 150mW Class AB LM4881 Headphone Amplifier Board

Here's a link to the TPA3116 2.1 board I'm working with. The ".1" subwoofer portion of the board has all the "pre-amp" components for summing the stereo signal and providing the low pass filter. I've reverse engineered that portion of the board. That may allow you to modify the board to suit your needs.

12V 50WX2 100W TPA3116D2 2 1 HiFi Digital Subwoofer Amplifier Verst Board | eBay
 
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