1176 *1 pin question

[rafafredd]

[quote author="tubejay"]What for?[/quote]

I´ll not use the lundahl at the input. It´s very clean. I will rather use a small and colored transformer, so that I can choose between color and clean (opamp) input. Anyway, it´s cheap to mount a little more components for the opamp input and I have plenty of 5532´s here, so, as the pads are there already on the board, I will just try it and listen to know if I will get different color from the two inputs...

 

[clintrubber]

from rafafredd:

I will just try it and listen to know if I will get different color from the two inputs...

I'm curious, already some further ideas & listening of the '5532' vs 'TX' (or who knows, also vs 'TX+5532') ?

 

[clintrubber]

Hi Rafafredd, any listening yet ?

Thanks,

Peter

 

[rafafredd]

No. I´m not working on my 1176s now. They are on the waiting list.

Many other projects.

 

[clintrubber]

OK, thanks.

Good idea of you anyway to just implement both options. :thumb:

No frontpanel made yet, so could still add an input-mode switch to select between TX or the 5532.

Just curious, if using the input-TX, is there some loading of the secondary (OEP-tx) required ? I figure not, otherwise it would have been on the MNats-PCB - but still, those older 1176-Rev-schematics have like 270 Ohms added.

Bye,

Peter

 

[clintrubber]

from rafafredd:

so that I can choose between color and clean (opamp) input.

Hmm, was thinking about that input-select switch, but just realized the consequence for the input-sensitivity is large:
if I'm not mistaken it'll be some 16 dB because of the 1:6.45 of the OEP inp-TX.

Perhaps don't want to transfer that job completely to the input-pot (?). Compensation for the added gain will be straightforward though - but it's just that I hadn't realized it before.


Hmm#2, that added gain makes me think of (from MNats' site):

Options for either OEP or Lundahl input AND output transformers. I believe the choice of the specified OEP input transformer allows the compressor to be used as a microphone preamp as well due to increased gain.

How about it, people have been trying this already ?

Bye,

Peter

 

[pahstah]

i tried to put both tx and opamp in the same unit and made them switchable by means of a relay on the input, i send then a cable from *1 to #1 and this is what happened: the opamp section works normally but when i switch to trafo (lundhal) i got hardly a signal and all the high frequency are attenuated..
paolo