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    New person question: CD Player into PAS 2: input points

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    jimfour


    Posts : 3
    Join date : 2013-01-03

    New person question: CD Player into PAS 2: input points Empty New person question: CD Player into PAS 2: input points

    Post by jimfour Thu Jan 03, 2013 1:17 am

    I recently pulled out of the storeroom an old Pas 2 I restored years ago – which sounds quite nice with the old AR turntable I hooked it up to. I also want to plug a simple CD player into it. Unfortunately, I went the miminalism route when I restored the preamp and tore out the big selector switch, leaving the phone inputs as the only active ones left.

    At what points on PC6 - or on the tone controls perhaps - can I re-establish a sort of line stage / CD player input routing? My knowledge of electonics is very rudimentary, basic kit-assembly stage, so I'm looking for a simple solution.

    thanks ...



    Last edited by jimfour on Thu Jan 03, 2013 1:19 am; edited 1 time in total (Reason for editing : spellling)
    peterh
    peterh


    Posts : 1832
    Join date : 2012-12-25
    Location : gothenburg, sweden

    New person question: CD Player into PAS 2: input points Empty Re: New person question: CD Player into PAS 2: input points

    Post by peterh Thu Jan 03, 2013 12:45 pm

    you might connect to tape input and use the "tape" switch.

    Why did you rip out the selector ???
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    jimfour


    Posts : 3
    Join date : 2013-01-03

    New person question: CD Player into PAS 2: input points Empty Re: New person question: CD Player into PAS 2: input points

    Post by jimfour Thu Jan 03, 2013 4:59 pm

    The tape input is no longer connected.

    I'm trying to read the schematics but it's difficult to follow the wiring paths through the selector. Eyelet 13 on PC6 is the left side hot phono input and eyelet 11 is phono ground, but I can't see where the tape head input connects into the circuit. Other eyelet input points getting wires from the selector are 12 and another group 7, 8 & 9.

    I took the selector out to make the thing a bare-bones phono preamp. This was in the eighties - never thought I'd have to get a CD player!
    peterh
    peterh


    Posts : 1832
    Join date : 2012-12-25
    Location : gothenburg, sweden

    New person question: CD Player into PAS 2: input points Empty Re: New person question: CD Player into PAS 2: input points

    Post by peterh Thu Jan 03, 2013 5:18 pm

    jimfour wrote:The tape input is no longer connected.

    I'm trying to read the schematics but it's difficult to follow the wiring paths through the selector. Eyelet 13 on PC6 is the left side hot phono input and eyelet 11 is phono ground, but I can't see where the tape head input connects into the circuit. Other eyelet input points getting wires from the selector are 12 and another group 7, 8 & 9.

    I took the selector out to make the thing a bare-bones phono preamp. This was in the eighties - never thought I'd have to get a CD player!

    Well - you cannot blame anyone !

    For a couple of hundred you can get a working one at ebay!
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    Flyquail56


    Posts : 24
    Join date : 2009-05-04

    New person question: CD Player into PAS 2: input points Empty Re: New person question: CD Player into PAS 2: input points

    Post by Flyquail56 Sun Jan 06, 2013 1:03 pm

    The CD player should not go through PC-6 at all. That board is for low-level inputs, and is equalized for phono.

    The most simple solution is to reinstall the tape monitor switch, which can be used as a two position selector switch.

    Since the selector switch and tape monitor switch are removed, then the output from PC-6 must be going directly to the blend switch, balance control, or volume control, depending on what's still there.

    Reinstall the tape monitor switch as shown in the original assembly manual, with tape amp, aka tape in (not tape head!) wired to one side of the switch, and output from PC-6 (eyelets 1 and 7) wired to the other side. The center lugs of the switch are wired to the blend switch, balance, or volume.

    Hope this helps.

    Mike


    Last edited by Flyquail56 on Sun Jan 06, 2013 1:06 pm; edited 1 time in total (Reason for editing : added eyelet numbers)
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    jimfour


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    Join date : 2013-01-03

    New person question: CD Player into PAS 2: input points Empty Re: New person question: CD Player into PAS 2: input points

    Post by jimfour Sun Jan 06, 2013 4:06 pm

    Flyquail56 wrote:The most simple solution is to reinstall the tape monitor switch ...

    Thank you. I thought the signal should go directly into PC5, just didn't know how to get it there – and wasn't sure if "tape" would be tape head or tape amp.

    The amp I'm using – an old Heathkit – doesn't like direct input from the CD player which my former Stereo 70 and Bogen 6V6 could handle. Circuit's a bit unstable and rich transients, like jazz organ, tend to wobble going through.

    I always liked the PAS, especially the big soundstage – though I've heard it characterized as too bright and "glassy" sounding. Will compare the PC5 sound to that from an old Bottlehead line stage amp kit I'm just completing.

    thanks again

    Jim
    Roy Mottram
    Roy Mottram
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    New person question: CD Player into PAS 2: input points Empty Re: New person question: CD Player into PAS 2: input points

    Post by Roy Mottram Wed Jan 09, 2013 2:39 pm

    with a system like yours, I'd use the tape-source switch for the CD input.
    You would connect the output of the phono preamp to the "source" side of the switch, and connect the CD input to the "tape" side of the switch.
    The common output of the switch would then go thru the volume control to the line stage.

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