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Project Specific Discussions => Magnetics => Topic started by: Ricardus on April 09, 2020, 09:36:21 PM

Title: Dibao Transformers
Post by: Ricardus on April 09, 2020, 09:36:21 PM
Has anyone done any testing or work with these? They claim to have a Lundahl LL1527 clone among others.

They sure look nice.

https://www.aliexpress.com/item/32963385840.html?spm=2114.12057483.0.0.6b7b3ee5JIaSCg
Title: Re: Dibao Transformers
Post by: ruffrecords on April 10, 2020, 04:43:27 AM
I don't know how the specs compare with a Lundhal but 1% distortion at 50Hz at +18dBu output is not very good in my book.
 for an output transformer.

Also, the case seems to be made of copper which is very much cheaper than the  mu-metal used in the Lundhal and also it useless at screening magnetic interference which is essential in a mic input transformer.

Edit: and at $57 each they are not much cheaper either.

Cheers

Ian
Title: Re: Dibao Transformers
Post by: gyraf on April 10, 2020, 11:23:12 AM
There's several Chinese companies claiming to make good 1527's, e.g.

https://www.aliexpress.com/item/32981126165.html  - probably there's just a single OEM and a lot of sub.brands

but as Ian points out, they don't care much about magnetic shielding, which is a very important parameter - just ask anyone fighting with the OEP-type transformers..

/Jakob E.
Title: Re: Dibao Transformers
Post by: ruffrecords on April 10, 2020, 01:56:25 PM

but as Ian points out, they don't care much about magnetic shielding, which is a very important parameter - just ask anyone fighting with the OEP-type transformers..

/Jakob E.

But to give them their due, OEP do offer proper mu metal screened versions.

Cheers

Ian
Title: Re: Dibao Transformers
Post by: abbey road d enfer on April 11, 2020, 11:52:50 AM
Both links are dead...
Title: Re: Dibao Transformers
Post by: gyraf on April 11, 2020, 12:08:36 PM
?? strange - here they open fine..?
Title: Re: Dibao Transformers
Post by: abbey road d enfer on April 11, 2020, 01:32:32 PM
Well, for me they open the AliExpress portal with leggings, dresses, furniture... :D
Title: Re: Dibao Transformers
Post by: Ricardus on April 11, 2020, 02:39:56 PM
But to give them their due, OEP do offer proper mu metal screened versions.

Cheers

Ian

Yeah. Whenever I use their traffos, and so far it's only been in some Bo Hansen DIs, I bought the addition mu metal screens.