Clearance above 300b tubes

[Chris H]

Looking to make the leap into Kaiju and BeePre but need to redesign my hifi rack.
I have space to extend upward but not sideways which means one of either BeePre or Kaiju will need to go on a lower shelf.
Natural inclination is to have Kaiju below with BeePre on top shelf.
How much clearance above the Kaiju is needed?

I understand tubes will generate some heat.  Will have good ventilation at rear and sides.
Shelves are solid 40mm walnut. OK to get hot but don't want it to get scorched.
Legs will be made to order and am currently allowing 290mm (11.42") total clearance which should give just under 2" clearance.
Is this enough and if not, how much should be allowed?

Thank you in advance for any suggestions or advice.

[Paul Birkeland]

The BeePre and the Kaiju will be the exact same height, but the Kaiju will run a LOT hotter than the BeePre will, so you may want to just pop the Kaiju up top.

[Chris H]

Thanks Paul.
Also on the top shelf will be the Eros.
I've always tried to maximise distance between power amp and phono hence why was looking at Kaiju lower down or should I not be concerned?
Assume 2" clearance above BeePre tubes is sufficient but would I need more for Kaiju tubes?

Chris

[Paul Birkeland]

It's tough to give you a definitive answer either way.  I've run some very hot tubes (838) about 1" below some maple ply and nothing scorched, but I've seen less heat damage other surfaces.  If it seemed too hot, a little moving air goes a long way.

[Chris H]

OK, that's understood regarding a defnitive answer.
I will stretch the headroom as far as I can and be prepared for either on top.
They both look good either way, it's just a shame I don't have room for both on top.

Worse case, I could rig up one or two spare low noise computer fans at low speed.
It's an old house - an extra blower heater in winter wouldn't hurt!

Thank you for the speedy replies as always.

Chris

[Doc B.]

I'm thinking a couple inches above the tops of the tubes as you propose would be adequate.

[Chris H]

Thank you for the advice.
Order placed for 1 x Kaiju.
I have just ordered the stock kit for now, holding off on BeePre until upgrades are available and will make decision on those and Kaiju filament upgrade then.
Rack redesigned to make space allowing for some swapping around of components if needed.
Pics are of current setup and redesigned layout.  Can't wait!

[Deluk]

If the TTPSU can tuck between the Eros and the BeePre you can drop the Kaiju down 105. That should help. Having the PSU closer to the TT is no bad thing.

[Chris H]

Thanks for the suggestion.
I have about 7 different layouts so far including ones where I lose a shelf.
That's the favourite at the moment and minimises number of new legs to buy.
I should have added, manufacturer recommends max 300mm (12"), or bolted legs for anything longer.  This may entail a new shelf.
Manufacturer probably being cautious but better safe than sorry!
If Kaiju is too hot on lower shelf I can swap with BeePre (which I am told is less of an issue).
Main concern is getting some distance between Eros and components that might cause noise.