A complete newbie builds KEL84 (hopefully)

[Shane]

Looking at the pic of KennyK's kit, a thought occurred to me, so here's daft question #276:

Is it possible to fit the transformers so that the cores are below the level of the top of the chassis and only the top covers are visible from the outside, and if it is possible, would it be likely to have any undesireable side-effects?

[david counter]

I think they're too tall to fit inside the chassis,
why would you want to do it?

[Shane]

Just my weird aesthetic sense. Valves look nice on top of the case. Transformers don't (definitely IMHO!).

[david counter]

only thing you could do is make a deeper chassis,
that's the trouble with being an artist

[Greg.]

Hi Shane,

Provided transformers used are well, maybe even over spec'd there is no reason why they can't be hidden inside the chassis. To be inside they need to run cool, so spec is an issue. These days everything is divided down to the minimum needed, hense modern Tx's tend to run hot, albeit that modern production makes this performance managable. Internal mounting takes up valuable space which can frustrate future tweaking or development of your amp. Generally O/P Tx's run cool and could easily be adapted to mounting in this way. Mains Tx's are different because they are more likely to generate heat and need the surface mount for cooling. If well and probably over spec'd that might not be an issue. The original WAD KiT/KaT88 had an internally mounted toroid Tx that got hot and didn't over-stress components closely mounted, but experience was that in terms of hum etc, the amp sounded best with the Tx mounted on the top of the chassis. I covered mine with a sprayed up old sausepan to make it look good

I know where you're coming from, but we have to work within reasonable limitations. You and I can talk on this. You'd be lost in a conversation with Nick and Paul where visual aesthetics have no priority, oh and space doesn't appear to be an issue

They do build great amps though.

Best wishes,

Greg

[Shane]

Thanks Greg, I thought there probably was a good reason why not.

I know what you mean about Nick and Paul's amps, but they do have a sort of wild, sod-you look about them that has an appeal all of it's own! God knows what the health and safety boys would think though.

[petercom]

Mains TFMRs always run hot in valve amps - they have a lot of continuous power to pump out in a Class A design. Of course the more money, and size, you throw at a TFMR the cooler it will run.

Over the years manufacturers have come up with lots of ways of 'hiding' transformers from costly plated covers to full size chassis. The drop through design that WAD and WD use reduces the height above the chassis and allows cooling of the laminations. If you don't like the look of 'em then a nice shiny box over the top will have the added advantage of reflecting the valves.

[Paul Barker]

Well for the short time I've been involved in scratch building there has been the Trichotomy. There are the ones who take a kit like the Dyna 70 or say a WAD kit, and they make it look the best possible, like chrome plating everything and just adding the final tweaks to the looks. Then there are the guys who do an imaculate scratch build, they cut each length of wire to be just so and route it just so. They design and implement the most beautiful metalwork, pure works of art. Then there are the guys who have a go at that, turn out something that looks like you made it in your own shed, throw in the towel and just pay no attention to looks at all, because it doesn't make any differnce if you can get those around you round to accepting it taking up 3/4 of the listening room, and you don't mind steping over it to change the record.

Oh and then when James says that wood sounds better than metal anyway, you think, that's a relief. No more pnching holes in metal yipee!

[KennyK]

Originally Posted by Shane

Looking at the pic of KennyK's kit, a thought occurred to me, so here's daft question #276:

Is it possible to fit the transformers so that the cores are below the level of the top of the chassis and only the top covers are visible from the outside, and if it is possible, would it be likely to have any undesireable side-effects?

I wondered about it and nearly did. but I realised that it would foul the phono sockets.

[KennyK]

just been wiring up my mains transformer and it looks like there's an potentially dangerous error in the instructions - if you follow the instructions to the letter they tell you to wire up the brown to the switch from the wrong end of the fuse, essentially bypassing it. therefore there's no protection.

if you've already completed the kit, try removing the fuse and making sure that it breaks the circuit.