I'm just looking... maybe you should consider buying from somewhere that doesn't require you to buy a million of everything.
Can't see anything in small quantities 🙁
Can't see anything in small quantities 🙁
Hello! Not gone away yet! 🙂 Life is just getting in the way with work and crap 🙁 Will be back with an update very soon 🙂
Well, got nearly all the bits I need. Except a couple of things. And they won't be delivered until sodding April!!! Thanks Brexit 🙁
Hello again. Whilst (still) waiting for some of my ordered parts to arrive, I've started collecting the parts to make this: A Complete Guide to Design and Build a Hi-Fi LM3886 Amplifier - Circuit Basics. As I had a couple of spare LM3886s around and I got hold of the PCBs for this project from a friend. I have almost every part except the transformer. I was going to order the exact same one, then wondered if it makes any difference that my domestic supply is 230v and this is based on a US 110v. Can someone let me know?
🙂 again.
It is vital that the transformer you use is suitable for your mains voltage. Many (but not all) transformers have the ability to configure the primary windings to suit the supply voltage.
I can't just see which specific transformer is recommended in that design but suitable ones for an LM3886 amp are available from many sources.
You need to decide what secondary voltage you want... and higher is not always better for reliability. An 18-0-18 transformer would give around 25-0-25 volts DC and deliver around 25 to 30 watts per channel into 8 ohms.
A 25-0-25 transformer would give 35 volt rails and deliver around 50 watts per channel.
Check the primary voltage can be configured to either 230 or 240 volts.
It is vital that the transformer you use is suitable for your mains voltage. Many (but not all) transformers have the ability to configure the primary windings to suit the supply voltage.
I can't just see which specific transformer is recommended in that design but suitable ones for an LM3886 amp are available from many sources.
You need to decide what secondary voltage you want... and higher is not always better for reliability. An 18-0-18 transformer would give around 25-0-25 volts DC and deliver around 25 to 30 watts per channel into 8 ohms.
A 25-0-25 transformer would give 35 volt rails and deliver around 50 watts per channel.
Check the primary voltage can be configured to either 230 or 240 volts.
This is the one used in the build...Vigortronix VTX-146-300-218 Toroidal Transformer 300VA 0-18V | Rapid Online
That one is OK. It has a dual primary which means you connect the two 115v windings in series to make a 230v one.
Look at the data sheet on that page. You connect the grey and violet wires together and apply 230v to the brown and blue.
Look at the data sheet on that page. You connect the grey and violet wires together and apply 230v to the brown and blue.
Attachments
That one is out of stock, so would this one be a good substitute?...Security Check
Or this one?...Security Check
Or this one?...Security Check
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The first one is OK but is quite hefty, you don't really need anything quite that large (the VA rating).
Second one is more suitable
Second one is more suitable

Back to the original amp: can I add a couple of inputs relatively easily? I need to add a CD player and a turntable. Is this something I can do with your help, without ruining everything so far? 🙂
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