nah.

It's just actively buffered ground.


For the recent months, I have some doubts and mixed feelings about three channel after reading jcx's analysis.

I have not done enough homework and testing on it yet but jcx's stand is that an active buffered ground with a very good star grounded layout, is better than three channel.

From his analysis, I can somewhat agree with it however I'm still far from actually testing it myself.

Assuming circuit simplicity is still in priority, would rail to ground cap be considered as a good alternative to provide more current?

can point me to the link ka bro

If you want simplicity, the best way is to not even use VGND at the first place. Just use single ended and use output caps. The GND is then a true GND with very lowest impedance possible from the PSU.

It's not to "provide" more current. It's that the current is now sunk by the caps instead of the TLE2426, which means that it's is going to affect bass if you do not have big enough caps.

I'd say yes, simplicity in question, caps after rail is still better.

never use this chip..how it sound

not an opamp

I don't know where to ask this, but is it ok if I put the volume on the amp full and control it only on my mp3 player?

Yes. You can.
Unless you amp gain is kinda high, there'll be some(or lots of hiss.)
I'd say mid position should be workable.

what type of amp do you used?

No, this is an ill manner of doing things.

Well, this is because the noise figure of the MP3 player remains pretty much the same throughout the entire output. You want to maximize the signal to noise ratio by putting it to max and control the volume using the amp. This way the relevant signal is at its loudest and the noise is small in comparison.

I'm using GoVibe Martini headphone amp. And yeah, the hissing is high at full volume So using half now. Thanks ya

Ohhh I see. So the best way is to put full volume on mp3 and control on the amp? Thanks

yes

Btw, what's the switch inside the amp? High & low

take pictures. It's hard to tell since we don't own one.


But my guess would be a gain switch. Which in all cases you should use the lowest settings as much as possible.

Is it sonically possible to build a prototype amplifier on breadboard? I just had a quick try with simple OPA2132. Ordinary jumper wires were used. Audio jacks would not fit on breadboard hence I used crocodile clips for input and putput. I know it sounds very wrong but the performance was way below expectation.

Constant hiss. Sounds like white noise. Terrible low frequency roll off; bass filtered even without any input capacitors. When the song goes through bassy passages, the entire volume dips down. Vocals are excessively wide soundstage. Singer sounds like singing in a hall. At complex passages, the roll off would affet the vocal as well i.e. Voice gets filtered like minus one track.

DC offset is normal (3mV) on both channel. Rail splitter appears balanced and stable during operation. No heat on battery, op-amp and TLE2426 rail splitter.

Could the breadboard and interconnects caused so much degradation or the problem is within the circuit itself?

This post has been edited by mengsuan: Dec 28 2010, 03:21 AM

What is it for bro? Can explain? It's not stated in the manual


This post has been edited by FaezFarhan: Dec 28 2010, 06:00 AM

Looks like a gain switch alright.

Yes, it's definitely possible. Both me and Ijan used to build big amps on breadboards and they'd still work properly. For Ijan, he even used a breadboarded amp for years before finally transferring the circuit into a perfboard (YES A PERFBOARD NOT EVEN PCB LOL).


Show some pictures of your build. This is most likely a layout issue. Then again CMOYs arent good performers especially if you listen loud and you're pushing the limits of the tiny little chips with no power.

Try having caps to rail after the splitter.

What is it for? Should kept at low?

as low as possible.