The TAD EL84 seems to be the strongest(?) tube available so I have one to put in. porterburst' post was a TAD also which stopped the rattle apparently.

I love this amp!  It sounds incredible and feels even better than it sounds.  It's extremely touch sensitive and just has an elasticity that makes single not lead lines scream and sing with beautiful sustain.  Double-stops sound clear and distinct and there's no ugly modulation when playing root and third doubestops.  This is my third Class 5.  I bought two early on and returned them both due to tube rattle issues I couldn't resolve, but after reading the success people have had in dealing with the tube rattles, I decided I gave up too soon and had to get another one because they sound and feel so great.  I think my expectations regarding tube rattle were a little unrealistic given the sonic footprint of this amp. I had also not explored all the tube options people have had great luck with.  Anyway, I have decided that my love of the sound and feel of this amp trumps what I may have to deal with in regards to tube replacement and I'm just going to play and enjoy this beast!  There's truly nothing like it in this size package, weight and price range.

Hi Guys,
I hope to help someone with this post:

finally I solved my trouble of rattling on Class5!

During past two weeks, I opened Amp and I followed all the technical suggestions indicated by Marshall on PDF file.
I removed the screen between valves and OT, I move away all cables from chassis and from transformers... I also change the socket for V3 (the EL84) since I founded it was too loose (it is composed by two parts joined on centre) and I replaced with a chassis type belton socket.

I reassembled the chassis on cabinet and I switch ON again the Class5.
My wonder: NO CHANGE! rattle is again with my like before.

So I ordered from an online store 2 new EL84 valves: 1xEL84 Electro Harmonix and 1xEL84 Golden Dragon.

Yesterday I swap valve from stock (JJ EL84) to the Golden Dragon.
As you can immagine, Rattles went away completely! NO MORE RATTLES.

My conclusion is that only Valves are the real problem on Class 5.

However, in my opinion this little amp has several problems since Anybody of us solved rattling problem in different way...


I think rattles will come again in the future, but at least I will know which will be the source, and I will not go crazy tightening all the screws every day!

Cheers

Samuele

That little amp must  have some magic for you guys to continue to deal with the issues I am reading on the amp.

It really is a bad mofo!  It's got 100w Marshall tone that won't knock the house over.

Well I have read many posts with guys having some pretty bold claims like you just made. I have yet try it or even see one of these amps for sale. Also I have always owned heads and cabinets and never a combo type amp. Right now the new Marshall JMD and the new Mesa Electra Dyne are on my short list.

This really is a great have at home amp or practice amp with great grab and go qualities.  I haven't heard a better 5w amp yet or 15w amp for that matter.  Very fat sounding for 5w, which is unheard of at that small of size.

Depending on what you want to do the little Class 5 is a great sounding amp. I would say that its the best sounding 5 watt I have heard. It doesnt do everything though. Im still trying to find pedals that the amp really likes. Kicking it in the front end is a bit tricky and can result in spikey harsh tones. So if you want more gain and a more overdriven sound its a tough task with the C5. I have a Budda SD18 combo that does the uber-gain thing so Im covered

I find this to be a stand-alone amp. Plug in and redline it.

It likes treble boosters or clean boosts.

It also likes the MXR GT OD! ALLOT!!

I was considering the Seymour Duncan Pickup Booster pedal as a pure clean boost. Im wondering if that would work well?

I have one I could try out and let ya know.....

the Class5 likes zvex box of rock for sure.
and OCD 4 for my taste.

Strike Three against this amp. I'm done. I just got the three piece back model & the rattle is still there. It is not as bad as the others but I am at wits end. I will not change the tubes & I will not try to adjust or pad it to make it work. It is a shame because I love the sound of this amp. Sending it back again for the third time.  I'm done.