Need advise for audio

Hello,
I'm a beginner with HW4 (less than one year). For the moment, and for my first step in this fantastic world, I'm using my HP laptop 4 go Ram computer, linked to my 3 manuals + pedal organ Content, using its internal audio. I have no problem, no latency at all, to play french sample sets, by-passing here and there some stops (because internal PC capacity) : Forcalquier, St Michel en Thierache and several demos from Sonus Paradisi (Tks to Jiri!).
Beside that, I've a good audio set up with following items:
- Technics turntable direct drive
- AGI model 511 pre-amp from USA
- Scientific Audio SAE 2200 ampli (2x100 watts rms) from USA
- a pair of speakers KEF 104 ab from UK.
All this vintage equipment is 36 years old (yes, 1978 when I was working in the new world!) and for me still one of the best set up. My question:
Can i use it with HW out of my PC (only one stereo 3.5mm outlet). Do I have to go through the pre ampli, or directly to the ampli???
The ampli has two RCA inlet (2 channels) hooked up to the pre-amp for the moment.
Thanks for your help and advise.
Rolland

Can i use it with HW out of my PC (only one stereo 3.5mm outlet).

Yes.

Do I have to go through the pre ampli, or directly to the ampli???

You don't have to go through the pre-amp, though it may be more convenient to do so if the system is also used for playing back from other sources.

Nick

Nick,
Thank u so much for your fast reply. This means I havé just to go with à câble équiped with one side a stéréo jack 3.5 mâle (from output off my laptop) and double RCA male ,thé other side, to plug: one into channel À, the second into channel B of my amp??
Best rgds
Rolland

Yes, exactly so.

Nick

If it's any consolation my home speakers are 25 years old and sound beautiful, and at Christmas I powered the church sound system from a 3.5mm laptop output running Hauptwerk connected to a MIDI enabled electronic organ that had decided not to work the day of the carol service apart from MIDI out. There are no shortage of interconnectors on Ebay that cost next to nothing you could try if necessary - once you find which size socket works then you can upgrade to unobtainium-coated whatevers if you must.