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Obtaining Transformer for LM3875 Kit in NZ

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Hi. Way down here in NZ freight is a huge issue... usually about twice the price of the product, especially from US. I'm finding it hard to find 300VA 2x22v transformers to suit the Audio Sector LM3875 Kit.
I'm a noob and want advice if a slightly different transformer is ok or what would have to change to suit them.

found these locally in NZ
https://nz.element14.com/vigortronix/vtx-146-300-224/300va-toroidal-transformer-2x24v/dp/2817701

18V [url]https://nz.element14.com/vigortronix/vtx-146-300-218/300va-toroidal-transformer-2x18v/dp/2817700?st=toroidal%20transformer.[/URL]

I want to make sure I can find and afford ALL the parts before ordering anything.

Also could you explain what should I expect the difference between the "classic" version and the "Premium" version to be?
 
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I assume you mean the Audiosector kit?

In the last page of the kit instructions, Daniel says this:

Based on that, for 8 ohm speakers 2 x 22V AC transformer is recommended, and for 4 ohm speakers 2 x 18V AC transformer.

In practice, I didn't find any drawbacks with using 2 x 22V AC secondaries with 4 ohms either, so that value can be a good overall choice.

So it depends on your load, but 2x18 should work fine for both.

I've used quite a few Vigortronix transformers from Farnell / E14 and have always been happy with the quality versus price.

Looking at the classic versus premium, the PCBs in the 'premium' are better quality (gold plated), and the kit comes with 'lower noise Kiwame resistors'.

The classic will be just fine, the premium isn't too much more expensive if you want better quality - depends on your tastes and wallet.
 
Thanks
yes, the Audio Sector LM3875 Kit... So lower voltage better than higher? how will this change the output power, if at all?

I have to replace my speakers for this purpose also, so don't have any yet, would like to DIY them also, pretty sure they will be 8 ohm, (or maybe 6 ohm if I buy those cheap JAMO's ive seen on trade me)

I've built a Raspberry Pi streamer with Justboom DAC to play my CD libraray (flac) from a plex server. and it works well. This is for listening while working in my studio (art) so doesnt have to be too high end
 
Thanks
yes, the Audio Sector LM3875 Kit... So lower voltage better than higher? how will this change the output power, if at all?

I have to replace my speakers for this purpose also, so don't have any yet, would like to DIY them also, pretty sure they will be 8 ohm, (or maybe 6 ohm if I buy those cheap JAMO's ive seen on trade me)

I've built a Raspberry Pi streamer with Justboom DAC to play my CD libraray (flac) from a plex server. and it works well. This is for listening while working in my studio (art) so doesnt have to be too high end
 
I just took of windings of to small toroidals that delivered to many volts, and thee same to a 1kw toroidal that gave dual 65 volt now its dual 32 volt, now delivering +/÷ 45 volt after rectifier, it's quite easy actually, haven't tried a ecore yet, I suspect it to be trickier
 
2x 24V transformer will be fine too, if you go with 8 ohm speakers; power wise anything in 200-400VA range will work fine. The amp actually sounds better with higher voltage (more lively and engaging). if you prefer more laid back sound, than lower voltage might work better.
Attached graph shows power vs supply voltage.
The premium kit comes with better resistors, and that will produce more refined sound, you may hear a difference or not, depending on your system and ears ;-)
 

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Hi Maakbow,

This one includes shipping, thats the good thing about mouser and digikey as well. It is Center tapped, but should work fine.

https://nz.mouser.com/ProductDetail/Hammond-Manufacturing/1182T12?qs=qPaGMJUC%2BSvy8n2QkfhQuQ==

these guys are good and ship to NZ

Power transformers - Internet shop Toroidy.pl

you could try aliexpress, but never bought transformers from them. Keep an eye out on trademe if your in no rush. I used to use jaycars, but I think they dont stock torroidals anymore. Good luck.
 
G'day Mate,


You will get free shipping on orders over $65 (iirc) so any transformer orders should be free freight. They normally ship on Toll or DHL and orders typically come overnight from Sydney. At least to Auckland anyway.


I've had nothing but good experiences with both Element 14 and RS components.
 
I just came across this thread and thought "Ive got a 400VA 22+22 I could sell, but by the time I read the tread Im now thinking Id sooner use it for a Peter Daniels build who I remember from my F5 build 10 years ago and nice to see still going, so my question is Peter what kit today has that "tube-like in harmonic content" the most as a contrast from F5 ?
 
that is not hijacking IMO. My transformer has just arrived...it weighs a ton. but any cheap source for NZers is welcome as...who knows, if this works out maybe ill be making another. Took a trip to the big city (aucks) this weekend and got some aluminium off-cuts from an engineering company to build the case. Just waiting for the kit to arrive and i can start the build
 
I’ve built them last year. The Raal tweeter came actually from Australia and the field coil Fertin drivers I had for a long time, but recently wasn’t using at all. They both match actually really nicely and made me believe that there’s no such thing as full range driver. For now it’s complemented by corner sub woofer, but I already acquired 4 SB Acoustcs open baffle woofers.
 

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