I think this subject is worthy of its own thread and I don't want to continue to hijack Alexc's post about eBay transformer cans, so I'm moving those posts from that thread into this new one.
The tape topic started off with this comment:
Quote:
"I’ve tried one of the 65x65x80mm steel cans from eBay you speak of. Quick and dirty test showed about 6dB noise attenuation. I lined the inside with 3M magnetic shielding tape, and subsequently measured 34dB attenuation. I ended up actually using that setup on the input of an AM-864 point to point build with an Edcor XSM 600:10k (wax potting)..."
AusTex64 asked what tape I used, and I replied that is was 3M CN-3190.
There are tapes that appear on paper at least to be better than the CN-3190 I ended up with. I bought that product because I found a deal I couldn't pass up. The stuff is marketed as a "conductive fabric" in the charts here, but in the datasheet, 3M describes it as EMI shielding tape with conductive adhesive. The datasheet claims ~70 dB attenuation for 3190, so it was good enough to my thinking.
Obviously, my measurements didn't get close to -70dB, but the tests I did were as close to "real world" for pro audio as I could get. And I only used a single layer of tape.
Take a look at the "EMI shielding tapes" chart below. You might want to look into those first. Or not.
The tape topic started off with this comment:
Quote:
"I’ve tried one of the 65x65x80mm steel cans from eBay you speak of. Quick and dirty test showed about 6dB noise attenuation. I lined the inside with 3M magnetic shielding tape, and subsequently measured 34dB attenuation. I ended up actually using that setup on the input of an AM-864 point to point build with an Edcor XSM 600:10k (wax potting)..."
AusTex64 asked what tape I used, and I replied that is was 3M CN-3190.
There are tapes that appear on paper at least to be better than the CN-3190 I ended up with. I bought that product because I found a deal I couldn't pass up. The stuff is marketed as a "conductive fabric" in the charts here, but in the datasheet, 3M describes it as EMI shielding tape with conductive adhesive. The datasheet claims ~70 dB attenuation for 3190, so it was good enough to my thinking.
Obviously, my measurements didn't get close to -70dB, but the tests I did were as close to "real world" for pro audio as I could get. And I only used a single layer of tape.
Take a look at the "EMI shielding tapes" chart below. You might want to look into those first. Or not.
![4CnK1RI.png](https://proxy.imagearchive.com/61f/61f1a544dbdd121d03e8da85c295b5dc.png)
![eFljTbL.png](https://proxy.imagearchive.com/f4d/f4d048d9ac55b4952cc2108782573a91.png)
![sNig4Bm.png](https://proxy.imagearchive.com/653/653bfef7a7cca3bfad7c4fd98500db1d.png)