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Dug out the SX-780...

steveinazsteveinaz Posts: 19,083
edited January 5 in 2 Channel Audio
Getting ready to put this 'ol girl back to work in my shop. Cracked the lid to blow it out a bit and have a look at the caps (Nicholson) which all looked good. This SX-780 was built in 1980 (Japan). Gonna replace the lamps while the lid is off, they all work, but I figure I'll do it now as they are original and easy to replace. I also need to de-ox the balance pot.

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Source: Bluesound Node 2i - Preamp/DAC: Benchmark DAC2 DX - Amplifier: Parasound Halo A21 - Speakers: PSB Imagine T2
Post edited by steveinaz on
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  • verbverb Posts: 8,240
    Nice looking unit Steve! It looks minty!
    Basement: Polk SDA SRS, Cary SLP-05 Pre, Enlightened Audio Designs CD Transport, Northstar Designs Excelsio DAC, Silnote Morpheus Ref2 Digital Cable, Marantz SA-14 SACD, McIntosh MC300 Amp, Furman 15PFi Power Conditioner, Pangea Power Cables, Wireworld Oasis 8 RCA IC's, MIT Shotgun S3 IC's, MIT Shotgun S1 Bi-Wire speaker cables
    Office: PC, EAR Acute CD Player, EAR 834L Pre, PASS ACA Monoblocks, Denon UDR-F10 Cassette, Acoustic Technologies Classic FR Speakers, SVS SB12 Plus sub, MIT AVt2 speaker cables, IFI Purifier2, AQ Cinnamon USB cable, Groneberg Quatro Reference IC's
    Spare Room: , Antique Sound Labs Wave AV-8 Monoblocks, Tisbury Mini Passive Pre, Tjoeb 99 tube CD player (modified Marantz CD-38), Analysis Plus Oval 9's, Zu Jumpers, AudioEngine B1 Streamer, Klipsch RB-61 v2, SVS PB1000 sub, Blue Jeans RCA IC's
    Living Room: Peachtree Nova Integrated, Cambridge CXN v2 Streamer, Furman 15PFi Power Conditioner, Polk RT265 In Wall Speakers, Polk DSW Pro 660wi sub
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  • oldrockeroldrocker Posts: 2,234
    Nice.

    Mine is on a shelf for now.

    Delivers a great sound with my DM4's.
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  • steveinazsteveinaz Posts: 19,083
    edited January 5
    It's an interesting story. Let me bore you with the details. Back in 1980, my best friend (Rob) and & I went to an audio "super sale" at the Checkerdome in STL. We both bought SX-780's and I also bought a Pioneer CTF-500 cassette deck. Fast forward to several years ago, I was able to make contact with Rob. My SX was long gone, but he still had his, which had been stored for over a decade. He sent me his, gratis, when he found out I was doing a 70's themed man cave. It IS mint, and I at least got him to agree to let me pay for the shipping. I had to agree to never sell it, and I did so willingly. So here she is!

    Tell you what, this thing is HEAVY. Nothing like receivers today. I'd bet it's near 20lbs.

    At the other house, in that HUGE RV garage, I had the 780 hooked up to a pair of ENERGY C-9 towers, and that SX could FILL that area (2500 sq ft) at incredible volumes thru those C-9's.
    Source: Bluesound Node 2i - Preamp/DAC: Benchmark DAC2 DX - Amplifier: Parasound Halo A21 - Speakers: PSB Imagine T2
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  • EndersShadowEndersShadow Posts: 16,936
    edited January 5
    oldrocker wrote: »
    Nice.

    Mine is on a shelf for now.

    Delivers a great sound with my DM4's.

    Gotta say I’d love to hear that pairing!
    "....not everything that can be counted counts, and not everything that counts can be counted." William Bruce Cameron, Informal Sociology: A Casual Introduction to Sociological Thinking (1963)
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  • DaveHoDaveHo Posts: 2,492
    Sweet looking gear. They don't make them that pretty any more.
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  • verbverb Posts: 8,240
    steveinaz wrote: »
    It's an interesting story. Let me bore you with the details. Back in 1980, my best friend (Rob) and & I went to an audio "super sale" at the Checkerdome in STL. We both bought SX-780's and I also bought a Pioneer CTF-500 cassette deck. Fast forward to several years ago, I was able to make contact with Rob. My SX was long gone, but he still had his, which had been stored for over a decade. He sent me his, gratis, when he found out I was doing a 70's themed man cave. It IS mint, and I at least got him to agree to let me pay for the shipping. I had to agree to never sell it, and I did so willingly. So here she is!

    Tell you what, this thing is HEAVY. Nothing like receivers today. I'd bet it's near 20lbs.

    At the other house, in that HUGE RV garage, I had the 780 hooked up to a pair of ENERGY C-9 towers, and that SX could FILL that area (2500 sq ft) at incredible volumes thru those C-9's.

    Not to thread jack, but I worked at the Checkerdome at that time (not that show, mainly Blues games and concerts) while I was in college! St Louis University! Small world indeed! :smile:
    Basement: Polk SDA SRS, Cary SLP-05 Pre, Enlightened Audio Designs CD Transport, Northstar Designs Excelsio DAC, Silnote Morpheus Ref2 Digital Cable, Marantz SA-14 SACD, McIntosh MC300 Amp, Furman 15PFi Power Conditioner, Pangea Power Cables, Wireworld Oasis 8 RCA IC's, MIT Shotgun S3 IC's, MIT Shotgun S1 Bi-Wire speaker cables
    Office: PC, EAR Acute CD Player, EAR 834L Pre, PASS ACA Monoblocks, Denon UDR-F10 Cassette, Acoustic Technologies Classic FR Speakers, SVS SB12 Plus sub, MIT AVt2 speaker cables, IFI Purifier2, AQ Cinnamon USB cable, Groneberg Quatro Reference IC's
    Spare Room: , Antique Sound Labs Wave AV-8 Monoblocks, Tisbury Mini Passive Pre, Tjoeb 99 tube CD player (modified Marantz CD-38), Analysis Plus Oval 9's, Zu Jumpers, AudioEngine B1 Streamer, Klipsch RB-61 v2, SVS PB1000 sub, Blue Jeans RCA IC's
    Living Room: Peachtree Nova Integrated, Cambridge CXN v2 Streamer, Furman 15PFi Power Conditioner, Polk RT265 In Wall Speakers, Polk DSW Pro 660wi sub
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  • steveinazsteveinaz Posts: 19,083
    Sweet! Once a year they would have model year-end super sales at the Checkerdome. I remember seeing a Pair of HPM 100's that had acrylic see-thru cabinets--awesome.

    I need to make a correction: Nichicon capacitors.
    Source: Bluesound Node 2i - Preamp/DAC: Benchmark DAC2 DX - Amplifier: Parasound Halo A21 - Speakers: PSB Imagine T2
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  • rooftop59rooftop59 Posts: 6,010
    I was 2 in 1980.

    Sweet reciever!
    Living Room 2.1: Dynaudio Contour 1.3mkii; Energy s10.2 sub; Cambridge Azur 851a; Cambridge Azur 752BD; Bryston BPD-1; NVidia ShieldTV
    Game Room HT: Denon AVR-X4200w; Definitive Technology SM350; Definitive Technology LCR2000; Definitive Technology Procinema 800; Mirage Nanasats; Sub - HSU VTF-2 MK5; LG UP870 4K BDP;
    ; Master Bedroom
    Cambridge Azur 551r; Definitive Technology SM45, ACI Titan Subwoofer Squeezebox Touch
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  • oldrockeroldrocker Posts: 2,234
    EndersShadow wrote: »
    oldrocker wrote: »
    Nice.

    Mine is on a shelf for now.

    Delivers a great sound with my DM4's.

    Gotta say I’d love to hear that pairing!

    Funny you say that.
    When I came to your GTG with the DM4's I almost brought it with me.

    Don't know what it is about those 2 pieces but they really work well together.



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  • honestaquarianhonestaquarian Posts: 2,523
    What's the power output per channel on this beast?
    I remember those days well. Most of the receivers looked like this one back then, with some notable exceptions like Sansui. These boat anchors were durable and sounded good.
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  • honestaquarianhonestaquarian Posts: 2,523
    Oh wait I see it on the meters in the close up pic. 50 wpc
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  • oldrockeroldrocker Posts: 2,234
    Need to pull her off the shelf.

    ybgbwt19q5ar.jpg
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  • EndersShadowEndersShadow Posts: 16,936
    oldrocker wrote: »
    EndersShadow wrote: »
    oldrocker wrote: »
    Nice.

    Mine is on a shelf for now.

    Delivers a great sound with my DM4's.

    Gotta say I’d love to hear that pairing!

    Funny you say that.
    When I came to your GTG with the DM4's I almost brought it with me.

    Don't know what it is about those 2 pieces but they really work well together

    Next time for sure!
    "....not everything that can be counted counts, and not everything that counts can be counted." William Bruce Cameron, Informal Sociology: A Casual Introduction to Sociological Thinking (1963)
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  • mhardy6647mhardy6647 Posts: 23,613
    rooftop59 wrote: »
    I was 2 in 1980.

    Sweet reciever!

    I graduated from freaking college in 1980...

    Nice lookin' SX-780 :)

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  • mhardy6647mhardy6647 Posts: 23,613
    From the SX-780 manual
    source: http://www.kallhovde.com/pioneer/sx-780om.pdf

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  • steveinazsteveinaz Posts: 19,083
    What have you fellow SX owners used for replacement lamps (faceplate illumination)?
    Source: Bluesound Node 2i - Preamp/DAC: Benchmark DAC2 DX - Amplifier: Parasound Halo A21 - Speakers: PSB Imagine T2
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  • oldrockeroldrocker Posts: 2,234
    Haven't replaced mine. They all still work...
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  • joecoulsonjoecoulson Posts: 3,717
    I was 5 in 1980 and full o beans
    Sweet looking receiver for sure. Love 70’s and 80’s gear. They looks so pretty compared to today’s gear.
    Auralic Vega G1/Rega TT/Denon SACD - Parasound P6 - PS Audio M700x2 - Elac Adante AF-61 - AQ Niagara 5000 - SVS SB16u
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  • joecoulsonjoecoulson Posts: 3,717
    Omg. That’s insane Mark!! Lol
    Auralic Vega G1/Rega TT/Denon SACD - Parasound P6 - PS Audio M700x2 - Elac Adante AF-61 - AQ Niagara 5000 - SVS SB16u
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  • mhardy6647mhardy6647 Posts: 23,613
    That's just the rack with the most seventies-era stuff on it (you'll notice a few imposters).
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  • steveinazsteveinaz Posts: 19,083
    I think I spy some Fischer or Scott tuners in that stack.
    Source: Bluesound Node 2i - Preamp/DAC: Benchmark DAC2 DX - Amplifier: Parasound Halo A21 - Speakers: PSB Imagine T2
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  • mhardy6647mhardy6647 Posts: 23,613
    Those be Sherwoods, young man.
    The Fishers and Scotts live on another shelf.

    All three brands were/are very good, but the sound quality of Sherwoods per dollar (on today's market) is, in my characteristically unhumble opinion, exemplary.

    11375465156_6aa8243414_o.jpggreat scott by Mark Hardy, on Flickr
    14815780530_d960f53533_o.jpgDSC_9821 by Mark Hardy, on Flickr
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  • mhardy6647mhardy6647 Posts: 23,613
    ... but I digress.
    Sorry!

    Unfortunately, I don't know squat 'bout no SX-780 :(
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  • aprazer402aprazer402 Posts: 1,542
    01hze5hpo7nu.jpg

    My SX-780 is resting at the moment, enjoyed it's sound with my older small Monitor 7's and 5 JR+'s.

    About four years ago I started using it again after several years. Low volume, easy loads. Then after about 2-3 months of maybe once weekly use, no output, powers on but nothing. Took it to the shop. Owner replaced one of two Darlington IC power packs (he said failed), less than $100.00. Okay, so now good. Take it home use it again, worked fine for about six months, then dead again. So I never took it back to the shop and that has been almost four years. Could be the other channel power pack has failed or the replacement was defective? Or something else? Unit is 9/10 otherwise.
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  • mhardy6647mhardy6647 Posts: 23,613
    edited January 6
    Good quality replacement "STK" power output packs for things like the SX-780 are notoriously hard to find. Many of the parts available today, regardless of source, are reputed to be counterfeits of poor, or at best, dubious, quality :(

    It is a major bugaboo* with the late 1970s into early 1980s mass(ish) market Japanese-brand hifi hardware (receivers and integrated amplifiers), unfortunately.

    Here's some example discussion on the subject.
    http://audiokarma.org/forums/index.php?threads/is-there-any-better-new-type-stk-0050.822331
    http://audiokarma.org/forums/index.php?threads/stk-0050-replacement-for-sx-780-and-others.721181/


    _________________
    * Major Bugaboo, of course, distinguished himself in the trenches in WWI. This is a different bugaboo altogether.

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  • aprazer402aprazer402 Posts: 1,542
    ^^^^ Thanks Mark. So another option could be the find a donor power pack from a used 780? Is the pack used for each channel identical or specific to L/R?
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  • mhardy6647mhardy6647 Posts: 23,613
    edited January 6
    I am not 100% sure, if the STK-0050 is a mono pack, it'll use two; if it's a stereo pack, it'll use one.

    EDIT: looks to be mono:
    https://www.digchip.com/datasheets/parts/datasheet/922/STK0050-pdf.php
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  • verbverb Posts: 8,240
    OMG! Professor does have an 8-track player! Don’t get me started, again! :smile:
    Basement: Polk SDA SRS, Cary SLP-05 Pre, Enlightened Audio Designs CD Transport, Northstar Designs Excelsio DAC, Silnote Morpheus Ref2 Digital Cable, Marantz SA-14 SACD, McIntosh MC300 Amp, Furman 15PFi Power Conditioner, Pangea Power Cables, Wireworld Oasis 8 RCA IC's, MIT Shotgun S3 IC's, MIT Shotgun S1 Bi-Wire speaker cables
    Office: PC, EAR Acute CD Player, EAR 834L Pre, PASS ACA Monoblocks, Denon UDR-F10 Cassette, Acoustic Technologies Classic FR Speakers, SVS SB12 Plus sub, MIT AVt2 speaker cables, IFI Purifier2, AQ Cinnamon USB cable, Groneberg Quatro Reference IC's
    Spare Room: , Antique Sound Labs Wave AV-8 Monoblocks, Tisbury Mini Passive Pre, Tjoeb 99 tube CD player (modified Marantz CD-38), Analysis Plus Oval 9's, Zu Jumpers, AudioEngine B1 Streamer, Klipsch RB-61 v2, SVS PB1000 sub, Blue Jeans RCA IC's
    Living Room: Peachtree Nova Integrated, Cambridge CXN v2 Streamer, Furman 15PFi Power Conditioner, Polk RT265 In Wall Speakers, Polk DSW Pro 660wi sub
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