I'm trying to get all the parts put together for my F4 build. Can anyone point me in the direction to look for a good UK supplier of mains transformers?
Tiger Toroids in Norfolk.
https://www.tigertoroids.co.uk/
The contact name is Stephen Foster.
Tell him it’s for audio and you need a stabilised core and a GOSS band. Ask for cloth wound and potted.
I’ve bought many transformers over the years but these are by a far margin the best. Absolutely superb.
https://www.tigertoroids.co.uk/
The contact name is Stephen Foster.
Tell him it’s for audio and you need a stabilised core and a GOSS band. Ask for cloth wound and potted.
I’ve bought many transformers over the years but these are by a far margin the best. Absolutely superb.
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You have to be wary of jellybean transformers. They’re ok for industrial applications, but don’t stack up to power transformers wound specifically for audio applications. I used Airlink but ditched them for my commercial stuff because the transformers worked ok but looked terrible - not the kind of thing you want a customer seeing if they opened the amp up.
I just received a custom order from Tiger Toroids, thanks to Bonsai earlier suggestion, the photo is attached.
I ordered earlier another 500VA custom toroid from Canterbury windings, but the owner is semi-retired and takes only several orders a month. Can try him. Not cheap, though.
I ordered earlier another 500VA custom toroid from Canterbury windings, but the owner is semi-retired and takes only several orders a month. Can try him. Not cheap, though.
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Hi All,
I'm very new to this so just want to make sure I ask for the right specs from Tiger Toroids, so would love your input if possible? Probably a stupid question, but how would these transformers compare to Talema / Triad medical grade range?
I'm building a streamer / DAC using IanCanada's parts. For the IV stage I am using his OPA861 board, which needs +/- 5V DC and using his LinearPi Dual low noise power supply (doc attached). In his documentation he recommends 2 independent coils, 2.5A or higher and 9V AC for a 5V DC application. I'm guessing 9V is because it is a standard but I can probably get away with 7V if I go the custom route to maintain headroom but not reach too high temperatures on the power supply?
So I guess what I am trying to confirm is:
Thanks
I'm very new to this so just want to make sure I ask for the right specs from Tiger Toroids, so would love your input if possible? Probably a stupid question, but how would these transformers compare to Talema / Triad medical grade range?
I'm building a streamer / DAC using IanCanada's parts. For the IV stage I am using his OPA861 board, which needs +/- 5V DC and using his LinearPi Dual low noise power supply (doc attached). In his documentation he recommends 2 independent coils, 2.5A or higher and 9V AC for a 5V DC application. I'm guessing 9V is because it is a standard but I can probably get away with 7V if I go the custom route to maintain headroom but not reach too high temperatures on the power supply?
So I guess what I am trying to confirm is:
- Is 7V the right secondary to ask for to get the right mix between headroom and keeping temperatures in check?
- Is 2.5A enough or is there any benefit of going higher? Do I need to specify it's 2.5A per coil?
- Looking at previous messages it seems I need to ask for: "flux density at 1T and always have a GOSS band fitted and an interwinding screen" and from earlier on this thread "stabilised core and a GOSS band. Ask for cloth wound and potted" though no idea what any of this means?
Thanks
I dispute that assertion - they are the same component doing the same job using the same copper and silicon steel (any evidence to the contrary?) - you can put the transformer in a can if you don't like the look (personally anything with cloth looks shady/sketchy in electronics to me!)
Come on - you don't really believe that do you?
The trick is in the core. Most toroid cores are simply plastic over-moulded and more often than not the core itself not particularly tightly wound. On general purpose commercial grade transformers, the core flux density is run at 1.3T.
On stabilized cores, the core is tightly wound and once over-moulded then vacuum impregnated. The transformer windings are then wound over this and the transformer is wrapped (take your pick - plastic or cloth - I prefer cloth) and then double vacuum impregnated again after which the core it potted.
Try an RS 500 VA transformer with some DC on the mains and most of them rattle away. Try a transformer wound on a stabilized core with low flux density (so it will be a bit oversized) and double vacuum impregnated and its dead quiet.
(I get my transformers wound by Tiger Toroids - I have no financial interest and gain nothing from sharing with fellow builders here what I've found using his products)
The trick is in the core. Most toroid cores are simply plastic over-moulded and more often than not the core itself not particularly tightly wound. On general purpose commercial grade transformers, the core flux density is run at 1.3T.
On stabilized cores, the core is tightly wound and once over-moulded then vacuum impregnated. The transformer windings are then wound over this and the transformer is wrapped (take your pick - plastic or cloth - I prefer cloth) and then double vacuum impregnated again after which the core it potted.
Try an RS 500 VA transformer with some DC on the mains and most of them rattle away. Try a transformer wound on a stabilized core with low flux density (so it will be a bit oversized) and double vacuum impregnated and its dead quiet.
(I get my transformers wound by Tiger Toroids - I have no financial interest and gain nothing from sharing with fellow builders here what I've found using his products)
Looks good 👍 🙂
(Make sure you ask for the finished product dimensions before ordering to make sure it will fit in your chassis)
I am probably spoiled and haven't used a low quality transformer that buzzes - DC on the mains is also something I've not had to deal with fortunately - All I've heard is a transient hum on switch-on. The toroids I've used all have silicone rubber washers to mount them which I guess helps suppress any noise getting to a chassis or enclosure, as well as protecting the windings.
Just banging the drum for Tiger Toroids again. Great service, very quick turnaround for my custom Pass F4 transformer!
RS have the nasty habit of supplying without mounting gear. Spec sheets are available on all so if say you buy an Xva transformer and use it at that you will know how hot it will get.