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Thread: Copland CSA 14, rework and upgrade.

  1. #1
    Join Date: Oct 2010

    Location: Ebbw Vale, Wales

    Posts: 31
    I'm Liam.

    Default Copland CSA 14, rework and upgrade.

    Hi Everyone,

    been a while since i have posted on here, my apologies, but life has been abit busy recently.

    The main reason I am here is to get thoughts from members on upgrading my beloved Copland amp. its coming on for 20years old now, and while built like a battleship one or two things have begen to crop up.
    namely one channel has began to cut out, if i have the amp switched off for a period of time.(therefore i leave it on), and dreaded 'crackling' has began to affect the volume switch, a failing alps potentiometer i suspect, i think this also effects the channel balance, but i dont use that in any case.

    Anyway, i was wondering if its maybe a case of having a look and simply rectifying these faults with new componets, or a more indepth look at what i have and upgrading aspects at the same time, with new capacitors, regulators, etc. as i am fairly electraiclly minded, ie i test and rebuild ECU's all day, I think I could perform said upgrades well.

    Would welcome any thoughts and suggestions on the matter, meanwhile here are a few pics of my innerards!




  2. #2
    Join Date: Jun 2010

    Location: Adelaide, South Australia

    Posts: 378
    I'm Steve.

    Default

    Hi Liam,

    I have a 1995 CSA14, I had a problem with the left channel over heating and eventually causing the cutout circuit to switch the amp off completely, this was traced to the valve in the left channel, now running NOS mullards and all my problems have gone.

    Nice amp isn't it

    Steve
    Steve.

    TT: 1986 Townshend Rock
    Arm: AO modified Moth RB250
    Cart: Nagaoka MP11
    Phono: Hagerman Bugle 2 - modded to 54dB (not in use)
    Mat: Plattamat 2
    CDP: Pioneer DVD 676A-S
    Digi: SB Touch
    Amp: 1995 Copland CSA-14 - 70s Mullard NOS 6922s
    Speakers: 1995 Castle Howard S1
    Headphone Amp: Musical Fidelity X-Can v3
    Headphones: AKG Q701

  3. #3
    Join Date: Oct 2010

    Location: Ebbw Vale, Wales

    Posts: 31
    I'm Liam.

    Default

    Hi Steve

    Thanks for the tip btw, havent really had any cutout issues, feel its more consistant with a dry joint or failing component, as channel is intermittant when cold.
    Have noticed that two of the big caps are bulging ever so slightly at the top, so i will be replacing them in due course.

    Lovelly sounding amp though, particulary with female voices, just started to take it apart today, so am getting my magnifying glass out tomorrow after work to have a good look at the pcb.

  4. #4
    Join Date: May 2008

    Location: A Strangely Isolated Place in Suffolk with far away trains passing by...

    Posts: 13,049
    I'm David.

    Default

    Might 63V caps last even longer, or will this upset things?
    Dave R

  5. #5
    Join Date: Oct 2010

    Location: Ebbw Vale, Wales

    Posts: 31
    I'm Liam.

    Default

    voltage doesnt really matter as long as its greater than the 50v thats currently present.

    just taken out all the caps, awaiting replacements atm

  6. #6
    Join Date: Mar 2010

    Location: Sheffield

    Posts: 1,985
    I'm Simon.

    Default

    Caps and valves will be a good start. let it run a few weeks then maybe think about the rectifiers, they aren't Schotky devices. Take a look at the volume pot, maybe a new one or a stepped attenuator of similar range and value.

    You really need to understand the circuit be fore doing anything beyond that, otherwise it's just pure guesswork. Best of luck with it.

  7. #7
    Join Date: Oct 2010

    Location: Ebbw Vale, Wales

    Posts: 31
    I'm Liam.

    Default

    Hi Simon

    am only going to recap and replace the potentiometers in any case, may have a look at the rectifiers later, as u suggested. The vales are new (old stock)siemens items, so they are fine, they just lost the markings when the pins were cleaned thats all.

    Any advice/recommendations when it comes to caps, and rectifiers? going maybe mundorf, not keen on alps though, stepped attenuators i may look into, any concerns over precise volume contol?

  8. #8
    Join Date: Oct 2010

    Location: Ebbw Vale, Wales

    Posts: 31
    I'm Liam.

    Default

    So finally got round to recapping the copland, took a while as i havent had much time to get round to it recently.

    It also gave me the oppourtunity to strip it down fully, have a look at the build quality and give it a clean and dust up.

    starting to strip it down, just making a note of what goes where, such as these power cables from the toroidal transformer.



    alps potentiometers on the volume, and the balance.



    electrolytics were joe masters, which i havent really come across before, so its difficult to know how to rate them.
    most electrolytics removed from the board, just a few at the bottom in order to not confuse myself, i replaced them in due course.

    By rabid1981 at 2011-09-26

    where the main powercaps sit.


    By rabid1981 at 2011-09-26

    some nice big mundorf 10000uf 63volts instead.


    By rabid1981 at 2011-09-26

    bare chassis, bar the transformer, and leads. Didnt replace them, just the brass ends due to oxidization.


    By rabid1981 at 2011-09-26

    front plate back on.


    By rabid1981 at 2011-09-26

    almost all done now, replacements were a little bigger than stock so where they were touching in just two cases, i glued a tiny peice of foam between them.


    By rabid1981 at 2011-09-26

    all back together and warming up!


    By rabid1981 at 2011-09-26

    nice night shot, turned it on, thankfully no hum or burning! lol


    By rabid1981 at 2011-09-26

    additioanlly the speakers hookups were replaced with HGC pure silver wire.
    the remaining caps were all fairly decent ELNA, NKZ, and Nichicon

    big difference, more than i anticipated if i am honest, seems theres more drive than before and detail too, hasnt really resolved the limited soundstage, but cant hope for everything. overall i would recommend giving it a whirl, especailly on amps coming upto 20 years old, like mine.
    only cost 150 in parts so much cheaper than a new amp.

    what say you? also have a Technics SL 10 refinish, if anyone is interested for me to post..

  9. #9
    Join Date: Aug 2010

    Location: Montseny National Park, Catalonia

    Posts: 3,256
    I'm John.

    Default

    Nice job Liam.
    Did you just do the caps?

    Always nice when nothing goes pop after these rebuilds.
    I've got an Exposure Pre and Power waiting for similar attention.
    Single spur balanced Mains. Self built music server with 3 seperate linear PSU, Intel i5, 16 GB RAM no hard drive (various Linux OS). Benchmark Dac2 HGC, single ended XLR interconnects/Belkin cable. Exposure 21RC Pre, Super 18 Power (recap & modified). Modded World Audio HD83 HP amp. Hand built Monitors with external crossovers , Volt 250 bass & ABR, Scanspeak 13M8621 Mid & Scanspeak D2905/9300 Hi. HD595 & Beyer 880 (600 ohm) cans.

    The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts.
    -Bertrand Russel

    John.

  10. #10
    Join Date: Oct 2010

    Location: Ebbw Vale, Wales

    Posts: 31
    I'm Liam.

    Default

    just the caps, may look at the rectifiyers at a later date.

    yeap, its always a relief! just totting up my copland cda266 for a recap and clock upgrade atm

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