Electronics > Projects, Designs, and Technical Stuff
DIY Headphone AMP, any ideas???
<< < (3/4) > >>
John B:

--- Quote from: nick_d on February 28, 2019, 01:14:42 pm ---As to amp specs, I am not really sure what the fuss is about. I built a lot of amps with LM358 or LM324 back in the day and never had a problem with them. I am aware they have horrible crossover distortion, I myself cannot hear it.

--- End quote ---

You must have loaded the op amp in such a way to keep it in one conduction mode. Crossover distortion has a lot of high frequency content and sticks out like a sore thumb. Always a good idea to feed in the maximum amplitude signal you expect in order to make sure that even the very crests of a signal aren't starting to distort from crossover distortion.

Anyways, on the topic you might get some ideas from this place:
https://www.jlmaudio.com/shop/amp-head-ii-phone-kit.html?display_tax_prices=1

Looks like they are using ne5532 op amps, maybe in parallel.

Been meaning to pick up a kit myself.


Just don't parallel them like this:

http://www.barberelectronics.com/parallelopamps.htm

 :-DD
DaJMasta:
I dunno, a "muscular" sound color may be just what the OP ordered in which case I think soldering opamps in parallel is probably the only thing I've heard of that will make that claim  |O
Conrad Hoffman:
A parallel design with some LME opamps would be good. Or, do a simple class A design. There are a ton of ideas on the 'net, with fans and detractors of all of them.
SiliconWizard:
You really need to define your requirements in order to select an adequate design, particularly in terms of max. output power and typical headphones impedance range.

Using a single opamp will not always be adequate. Unless you specifically use an high output current one, most will not be able to deliver more than +/-20mA or so (if that) without an enormous amount of distortion. With typical 16-ohm headphones, that's about 6mW! So, that could be enough for small earbuds, but with standard headphones (especially the lower impedance ones), the output level will be very faint.

Paralleling several opamps can work (with some precautions), but frankly unless you're targetting something very specific, I wouldn't bother, and I'd use an off-the-shelf headphones amp such as the one jeffheath suggested (there are many on the market, either class AB or class D): they can put out a lot more power and usually have integrated protections and such.

For a discrete design, class A is one of my favorites for that. Not efficient at all energy-wise, but will get you very low distortion with very few parts if done right.
Bassman59:

--- Quote from: cterawskyj02 on February 28, 2019, 09:05:57 am ---Hey guys, this is my first post and i am wanting to build a headphone amp, more because i can than any other reason, my PC does OK.
But i am looking for ideas, or if any one has made one or seen a good post on how to make one. Let me know.

--- End quote ---

Use the OPA551. It is available in DIY-friendly 8-pin DIP. You need two, as it's a single amplifier chip. It has enough oomph clean the wax outta your ears.
Navigation
Message Index
Next page
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod