SMD Capactitors for Amp

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I want to start using SMD capacitor on my diy amplifier. But it seem there is not a lot of topics about use SMD cap for amp in positions like:

- Local Decoupling.
- Cap multiplier output / filtering
- Feedback Capacitor
- Bootstrap Capacitor

I planed to go with either but Pana FK / UCC MVE but cant decide yet Do anyone already have experience about use SMD cap and can share with me?
 
SMD capacitors behave exactly as other capacitors including electrolytic types.
All that matters is the use of lead free solder to avoid leaching the silver conductor away from the connections.
They are more convenient to use as well, take up less space and come in various sizes. I frequently use 0402 size but for higher voltages up to 1005.
Read the specifications when you purchase them.
Examples include;
Electrolytic: Aluminium Capacitors | RS Components
Low value: Capacitor Sample Kits | RS Components
Resistors: Surface Mount Fixed Resistors | RS Components
Don't be fooled by "recommended makes" purchase Vishay, AVX, Murata, Philips etc. Known quality makers with a good stable history.
Most of all, read the specifications before choosing the wrong component for the job you have for them.
 
Hi Jon

I am looking to SMD more, mostly because the transistor parts that I like to use are being phased out in through hole form. The transistors that I am looking at for SMD are obvious (I like ON semiconductor) however, now that I am looking at the resistors, I am lost. The resistors that I use now are .6w and would like to stay near that or over, however, when I look for the values that I need, I find only some. The through hole types are far easier to find for me. I would like to stay within a series if I could for aesthetics and control etc.. What series do you use? I looked at the RS link that you provided and like I said, I find some here and some there.. I'm good on space for the 2010 size
Thoughts?

Thanks
S
 
Thanks Obscurus

Another reason that I am inquiring
Here is a snippet from a Suzyj blog..

" I wondered if I could improve the THD a little by winding up the negative feedback. This has the effect of reducing the output level, but I can sort that with more gain in the preamp. So I substituted a 5K1 MELF resistor for the 15K thick-film 1206 that was setting the feedback ratio. Bam! Instant huge improvement in THD. Much better than the couple of dB that I should have gotten. So I tried a variety of other MELF resistors for Rf. All show dramatically improved THD over the 15K thick-film chip resistor, and a gradual increase in THD in line with reduction in feedback:"
 
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Thanks Obscurus

Another reason that I am inquiring
Here is a snippet from a Suzyj blog..

" I wondered if I could improve the THD a little by winding up the negative feedback. This has the effect of reducing the output level, but I can sort that with more gain in the preamp. So I substituted a 5K1 MELF resistor for the 15K thick-film 1206 that was setting the feedback ratio. Bam! Instant huge improvement in THD. Much better than the couple of dB that I should have gotten. So I tried a variety of other MELF resistors for Rf. All show dramatically improved THD over the 15K thick-film chip resistor, and a gradual increase in THD in line with reduction in feedback:"

Thick film resistors are a big NO in audio circuits, by themselves they are both noisy and unlinear....

Use Thin film, like Susumu RR series, Digikey and Mouser have very good stock on those.
 
Thick film resistors are a big NO in audio circuits, by themselves they are both noisy and unlinear....

Use Thin film, like Susumu RR series, Digikey and Mouser have very good stock on those.

I'll agree, and add that the Susumu RG series is only a little more expensive than the RR series, far more stable, and readily available at Digikey and Mouser. The NiCr resistance element is sealed with a glass-like coating and laser trimmed through the glass, so their drift is extremely low. The RR series is sealed in resin, and it's less stable over time.

You can get lower temperature coefficients in the RG series too, something I feel is important to counteract their physically small size and the resulting potential for distortion from signal induced heating of the element. Their 10ppm/degree parts are extremely stable and sound/measure very well, and the standard 0.1% 25ppm RG parts are no slouch either. The Panasonic ERA series are almost as good, but the Susumu RG are a little better IMHO. The 2012 size is about as small as I'd use - they make smaller 1608 parts that seem to be more common, but I don't trust those to have low enough distortion. 3216 would be a better size than 2012, but they're not generally available off the shelf in oddball values.

I have used some larger thick film resistors for some power supply uses, but only because at low values like 100Ω, they really aren't completely awful, and in this case they are loaded into a giant 470µF cap and then a regulator, so their noise and distortion will be lowpassed and regulated away. Other than a few exceptions like this, where I needed the huge size and power rating of a thick film, never use thick film for any audio use.
 
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