Hi,
I was wondering is the Lundahl LL1540 can be a good choice for SY's Heretical line stage.
http://www.lundahl.se/pdfs/datash/1540.pdf
It can be configured as 1:1 or 1:2 to give some boost (if needed), what do you think about it (electrically and soundwise)?
Cheers
Andrea
I was wondering is the Lundahl LL1540 can be a good choice for SY's Heretical line stage.
http://www.lundahl.se/pdfs/datash/1540.pdf
It can be configured as 1:1 or 1:2 to give some boost (if needed), what do you think about it (electrically and soundwise)?
Cheers
Andrea
Hi,
thanks for the reply.
I have another question: in case I need to use them as step-up (1:2) the source would see 1/4 of the input impedance (roughly equivalent to the potmeter paralleled to the 15K resistor in your schematics.
Do I need to adapt these values to keep the impedance at about 10k?
Is there a particular reason to use a 100K pot with a paralleled resistor instead of a lower value pot?
I ask because I have on hand a motorized 50k blue velvet and a 20k black velvet...
Cheers
Andrea
thanks for the reply.
I have another question: in case I need to use them as step-up (1:2) the source would see 1/4 of the input impedance (roughly equivalent to the potmeter paralleled to the 15K resistor in your schematics.
Do I need to adapt these values to keep the impedance at about 10k?
Is there a particular reason to use a 100K pot with a paralleled resistor instead of a lower value pot?
I ask because I have on hand a motorized 50k blue velvet and a 20k black velvet...
Cheers
Andrea
Another lundahl transformer for the heretical...
http://www.lundahl.se/pdfs/datash/1545a.pdf
Can I use it without any changes in the schematic if I'd choose R4B / R4U : L4B / L4U connection?
Thaks SY
Mark
http://www.lundahl.se/pdfs/datash/1545a.pdf
Can I use it without any changes in the schematic if I'd choose R4B / R4U : L4B / L4U connection?
Thaks SY
Mark
I've used the LL1540 as an output to a balanced 12b4 line stage, and it sounds fine in parafeed - doesn't overload to my ears. I don't think it likes many volts of signal through it, though, so a low mu valve might be required. A friend put it on the scope with a 3A5 driving it (higher mu) and found that it was overloading.
Thanks Stuart.
I'll try to assemble it as soon as possible.
Just another question ( a bit OT, sorry): I've read the DiyAudioMag article about the heretical line stage and, in the last schematics, I can't see how you feed the opamp. I suppose using the +/-12V supply...I'm right?
Mark
I'll try to assemble it as soon as possible.
Just another question ( a bit OT, sorry): I've read the DiyAudioMag article about the heretical line stage and, in the last schematics, I can't see how you feed the opamp. I suppose using the +/-12V supply...I'm right?
Mark
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