[scytheavatar]

I think that with the closer component placement and the lesser inductance/capacitance due to not having the component wires a SMD based amp probably will have a better performance than a through hole amp. Plus SMD parts are cheaper than through hole parts. I know that getting those large capacitance for SMD parts is a bit difficult, or how through hole op-amps are more easy to roll, but then we can have a hybrid SMD/through hole design. The whole 'SMD parts are hard to solder' is complete bullcrap, it is hard at first but once you get used to it you'll think that through hole is a hopelessly obsolete technology. So why aren't the amp designers using more SMD parts?

 

[cotdt]

not true, even switching amps operating at very high frequencies do just fine with thru-hole components. i've builty many such things and they sound great.

 

[_atari_]

I asked the same thing myself!

Of courser there are people just loving through the hole stuff more.

But SMT offers a lot advantages: No question if the leads are magnetic, cheap and good components. For crititcal components (like capacitors) you can still use through the hole. Builds should be much smaller.

And most modern components (i.e. chips, like DACs & stuff) are only available as SMT.

So what are the disadvantages?
Which SMT parts are considered as 'high end compatible'?

 

[Pars]

Quote:

Originally Posted by _atari_ /img/forum/go_quote.gif I asked the same thing myself! Of courser there are people just loving through the hole stuff more. But SMT offers a lot advantages: No question if the leads are magnetic, cheap and good components. For crititcal components (like capacitors) you can still use through the hole. Builds should be much smaller. And most modern components (i.e. chips, like DACs & stuff) are only available as SMT. So what are the disadvantages? Which SMT parts are considered as 'high end compatible'?

The disadvantages would include much greater difficulty in repair/rework of a PCB or design than thru hole in most cases. Large pin count ICs are probably easier to change in SMT than thru hole parts would be however. Most amps etc. aren't using parts like these. SMT in many ways seems to lend itself to a throw-away mentality.

 

[_atari_]

Quote:

Originally Posted by Pars /img/forum/go_quote.gif The disadvantages would include much greater difficulty in repair/rework of a PCB or design than thru hole in most cases. Large pin count ICs are probably easier to change in SMT than thru hole parts would be however. Most amps etc. aren't using parts like these. SMT in many ways seems to lend itself to a throw-away mentality.

Hmmm, that is one of the most interesting points I have heard so far. Never thought about it that way.

You need a ompletely different kind of tool kit to work with SMT as effectively as with through the hole. I have an hot air reflow station - and swapping parts is much easier than with through the hole. But it was a painfull learning process towards it.

But I associate small and elegant with SMT.

I would really like to see an fully discrete SMT amp. Think of beta22 in a mint tin (I know it is not possible THAT tiny - but to get a picture). What do you think?

 

[MrSlim]

Quote:

Originally Posted by _atari_ /img/forum/go_quote.gif I would really like to see an fully discrete SMT amp. Think of beta22 in a mint tin (I know it is not possible THAT tiny - but to get a picture). What do you think?

Hmm.. Now what I would really like to see is how you'll mount the heat sinks on those teeny tiny transistors..

 

[MrSlim]

here's a couple of links on DIY reflow devices:
Reflow Skillet: SparkFun Electronics
DIY SMD hot air gun: How-To: Make a surface mount soldering iron - Engadget

 

[tomb]

Quote:

Originally Posted by MrSlim /img/forum/go_quote.gif Hmm.. Now what I would really like to see is how you'll mount the heat sinks on those teeny tiny transistors..

Exactly. Most of the better headphone amp designs are biased into Class A and thus need to dissipate qutie a bit of heat. This negates much of the advantage of using SMD. Similarly, the needs for capacitance often dictate larger electrolytics which don't lend themselves well to SMD.

There are some exceptions, to be sure. Pete Millett's TTVJ Millett Hybrid Portable comes to mind. I believe it's mostly SMD with pixie tubes. There's also the PPAS which is totally SMD. Tangent's PINT was another.

 

[DaMnEd]

Quote:

Originally Posted by _atari_ /img/forum/go_quote.gif Hmmm, that is one of the most interesting points I have heard so far. Never thought about it that way. You need a ompletely different kind of tool kit to work with SMT as effectively as with through the hole. I have an hot air reflow station - and swapping parts is much easier than with through the hole. But it was a painfull learning process towards it. But I associate small and elegant with SMT. I would really like to see an fully discrete SMT amp. Think of beta22 in a mint tin (I know it is not possible THAT tiny - but to get a picture). What do you think?

I think I have seen a SMD version of the B22, unofficial made by some asian dude, some pics where posted on headwize.com a couple of weeks back, the headwize forums are offline atm, when they comeback have a look their.

(I do not know if that SMD design was authorised by AMB, I think it wasn't since he didn't comment if I remember correctly, but it maybe worth a look)

 

[pabbi1]

I simply cannot solder SMT to save my life.

 

[amb]

Quote:

Originally Posted by DaMnEd /img/forum/go_quote.gif (I do not know if that SMD design was authorised by AMB

It was not authorized by me. This "dude" is actually selling assembled boards and making profit. I urge everyone not to patronize him.

 

[DaMnEd]

Quote:

Originally Posted by amb /img/forum/go_quote.gif It was not authorized by me. This "dude" is actually selling assembled boards and making profit. I urge everyone not to patronize him.

Sorry for mentioning it then :\

I only did because the post remained in their visible faik :|

I can edit my post if you want!

 

[amb]

Don't bother editing posts. It is what it is, and does nothing to stop anyone from taking a free ride on other people's work.

 

[mape00]

I agree, I too think SMD would be a much better option in most cases. One problem that I can think of is that not all people have the ability to solder SMD consistently regardless of the amount of training (lack of fine motor skills maybe).