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    cary audio design SLM-100 Monoblock's with my PAS 3



    Posts : 37
    Join date : 2011-09-04

    cary audio design SLM-100 Monoblock's with my PAS 3

    Post by pscottlowe on Thu Sep 29, 2011 5:39 pm

    I have a dyna pas-3 pre amp and am looking at a pair of cary audio design amps that have an input sensitivity of 750 mv and an input impedance of 150 k ohms. Is my pre amp compatable with these numbers? t [ i am now using an ST-70 to drive a pair of Klipsch LaScalla speakers and need more power ] Thanx for all your help. I also wondered about a mod for the PAS 3 that was mentioned when i talked about using a beringer 2496 to both time align the drivers {the midrange is 2 feet behind the tweeter and the woofer is 5 feet behind the tweeter it also is an active crossover that will " really open up the midrange " } this was from a tech that i use ,and i trust him .anyway i thank you. I would like to use these amps. I hope they will mate well with my system , Thanx again , Scott.


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    Re: cary audio design SLM-100 Monoblock's with my PAS 3

    Post by GP49 on Fri Sep 30, 2011 12:25 am

    You say you have a Dynaco PAS-3...not a PAS-3x for which the instructions are different.

    The Dynaco PAS-3 in stock form is designed to drive a 470KΩ load. The 150KΩ load of the Cary amp will cause a roll-off in the bass. To correct this, disconnect the 62KΩ load resistors on the linestage circuit board of the PAS-3 (I'd suggest lifting one end to disconnect them; they can easily be restored later if you want). Remove the 510KΩ load resistors at the output jacks of the PAS-3 and replace with 100KΩ resistors. This will provide an acceptable match to amplifiers of 100KΩ to 200KΩ input impedance.

    There is no modification other than major circuit redesign, such as adding a buffer stage or a cathode follower, that will enable a PAS-3 to drive that Beringer unit or anything else with a similar, low input impedance.

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