BBBMU

[Dr Bunsen Honeydew]

Big Bastard Balanced Mains Unit is finished and running. It will now cover all my system and builds and development work as it has 12 outputs = 6x13amp, 4x15amp, and 2xSchuko.

Surprisingly quiet, as I thought the jump from 1kva to 5kva would make it more noisy, it hasn't. Will report on musical benefit later.



Needs a crane to move it, I haven't weighed it but I would estimate it is nearer 40kg than 30kg.

[Fretless]

40 Kg ! - So no free postage then?

Looks seriously massive Doc - I expect it'll give you much pleasure.

[Dr Bunsen Honeydew]

It is not for selling, it is for me, so hopefully apart from pushing further back to the wall it wont need moving. I still don't think the change from 1kv to 5kv will make much of a difference, what makes the differences is case construction and earthing, as a BMU is far safer and better constructed as a Class 2 (double insulated) appliance than those rattly steel industrial Class 1 (earthed case) jobbies others are using.

[BilliumB]

Interested to hear how it turns out on musical benefit.

Do you expect that the lower impedance will have a significant effect?

Cheers. Bill

[Dr Bunsen Honeydew]

No. It has been built as I need lots of sockets which meant bigger box so I might as well use larger transformer, 1kva is ample for normal hi-fi system. Transformers vary in noise because the winding process varies, so I have been lucky with this one, another one I may have been unlucky, and that is the trade off - transformer noise v size.

[BilliumB]

That's good news on the transformer noise.

Looking forward to your listening experiences.

Cheers. Bill

[Dr Bunsen Honeydew]

I have definitely got weird mains here. The transformer in the BBBMU has suddenly started buzzing like mad, it had a couple of bouts of it earlier today, it has lasted less than 5 mins and now it has gone much quieter again. There is still noise acoustically from the transformer which shows the mains here not to be generally that good, but you have to be near it to hear it. Something around us (probably in a factory) is really putting shite on the mains intermittently. It is probably the case that these bouts of bad mains coincided with the system going off song that I noted before. The BBBMU should solve that.

[BilliumB]

Does acoustic noise / vibration on the BBBMU transformer have any impact on the 'musicality' of thr follow on kit, or is it totally irrelevant as long as the noise itself isn't intrusive?

Cheers. Bill

[Dr Bunsen Honeydew]

The point of the BMU is it does its job no matter what happens before it. So the only agg is the acoustic noise from the transformer. AND once again the bigger the transformer the more the problem, this was no where near as bad with the 1kva.

I am going to pack the BBBMU box with damping foam and put more doping on the transformer - later on when I have found some time.

[AshM750.]

Very nice Doc, that's a great achievement! What a big beast!