Can Lundahl ll1539 replace ll5402?

Hi.
I am wondering if I can substitute the ll5402 unbalanced line driver with the ll1539 balanced line driver with out adding a balanced driver circuit?

In other words, can I hook up the ll1539 as if it where a ll5402?

Will the performance be noticably poorer than just using a ll5402?

Are there any benefits to using a balanced drive, or is it just dependant on the circuit?

Would for example the many projects that use it, such as the G 1176, benefit in any way?

Thanks,
Hejsan

As the transformers are not the same, performance will be different.

To find out HOW different, and at what aspects, you need to consult the data sheets of the mentioned types and crosscheck with the parameters of the design you want it to work in.

Jakob E.

Hi. thanks for your reply.

I do however not know enough about transformers to be able to find out myself.

I can read from the datasheet that the transformer is more than good enough when driven by a balanced source, but I just have no experience in driving a balanced transformer, so:

1) I would like to know if it is doable to easily mod single ended circuits to use a balanced trafo.

2) I would like to know if a balanced trafo can be hooked up as an unbalanced one, especially if the LL1549 can be hooked up as a LL5402, since I have a few LL1549, but most (trafo out)circuits here seem to use LL5402.

3) If you think I'm out of luck, any suggestions for using the LL1549's would be appreciated.


Thank you very much,
Hejsan

I have no direct experience with the LL1539, but its parameters are such that it is optimized for balanced drive compared to the LL5402. I strongly suspect that it will sound somewhat different, but you are going to have to try it to find out.

I have done two 1176 with the 1539 and they sound great.
I never found any downsize soundwise.
But they will not fit in Jakob's PCB, so I made a small extra board.

[quote author="Michael Krusch"]I have done two 1176 with the 1539 and they sound great.
I never found any downsize soundwise.
But they will not fit in Jakob's PCB, so I made a small extra board.[/quote]

Hi, could you please explain how you hooked it up? The 1539 has two more pins than the 5402. Did you leave some of them out?

Thanks,
Hejsan

[quote author="Michael Krusch"]But they will not fit in Jakob's PCB, so I made a small extra board.[/quote]

[quote author="Michael Krusch"][quote author="Michael Krusch"]But they will not fit in Jakob's PCB, so I made a small extra board.[/quote][/quote]


:green:

Toff

Hey can the ll1539 be wired as 1:2 ?
The datasheet says 2 : 1+ 1  but there are two primary windings...

saint gillis said:

Hey can the ll1539 be wired as 1:2 ?
The datasheet says 2 : 1+ 1  but there are two primary windings...

Click to expand...

Old thread....

I guess for 1:2 you need to connect it backwards

hejsan said:

Hi.
I am wondering if I can substitute the ll5402 unbalanced line driver with the ll1539 balanced line driver with out adding a balanced driver circuit?

In other words, can I hook up the ll1539 as if it where a ll5402?

Will the performance be noticably poorer than just using a ll5402?

Are there any benefits to using a balanced drive, or is it just dependant on the circuit?

Would for example the many projects that use it, such as the G 1176, benefit in any way?

Thanks,
Hejsan

Click to expand...

Why not drop Per Lundahl an email? He's always happy to help.