Pioneer SX-680 vs SX-650

[Rob_Feature]

My main receiver for a couple years has been a SX-650 and it's served pretty well despite the slight 'muffle' (too much low-mid) that I hear across all Pioneers I've owned (I 'fix it' with a 10 band Marantz EQ the best I can...).

Today I picked up a SX-680 for $17 at the thrift (score!). I actually kinda anticipated it would be half-busted, but I just fired it up and all is well. Actually better than that...it sounds great!!

What gets me is the model numbers being so close to each other, but the looks and sound being pretty radically different. The 680 sounds more 'scooped' (like my Sansui) and has less low-mid mud. I was going to clean it up, cap it, and re-sell to a friend, but I'm thinking I may keep it.

So...looking for a little context: How can 2 receivers with such close model numbers look and sound so different? (obviously...because they're different....but how? are they different eras? radically different electronics? I would have expected a 650 and 680 to be almost the same with slightly different power ratings or something)

Anyway...any enlightenment from the Pioneer nerds? Gracias, Amigos!

 

[larryderouin]

X2x series 1972-1974 (424-525-626-727-828) All Discrete, 1st series of the Silver faced Pioneers
X3X series 1974-1976 (434-535-636-737-838-939-1010) Discrete with a few IC's. Developmentally improved from x2x series
X50 Series 1976-1978 (450 to 1050) Redesigned all Silver faced, More IC chips, Mostly All Discrete output's
X80 Series 1978-1980.(580 to 1980) Slight layout improvement, More IC Chips. Lower end of the series used STK Modules for output sections.

Read the "PIONEER Equipment Database" STICKIES by Dr. Strangelove http://audiokarma.org/forums/index.php?forums/pioneer-equipment-database.126/

 

[SaturationPt]

Is this the SX680 and SX650 for sale on Detroit Craigslist where the 680 is "just out of storage" or just a coincidence?

https://detroit.craigslist.org/okl/ele/d/pioneer-vintage-receivers-sx/6258837499.html

 

[Rob_Feature]

Actually those are mine, but the 'just out of storage' comment was apparently copy/pasted from the OTHER receiver I'm selling (which DID just come out of storage): https://detroit.craigslist.org/okl/ele/6258881416.html I didn't realize I put that on this post too, thanks for the note, I'm correcting that now!

I've got about 6 more receivers in storage from the past 10 years of picking (I pick them up at the thrift when I see them cheap, restore or use them as necessary, then they go back into storage). Slowly pulling them out, testing them and seeing what's what! The 680 is fresh from the store, though...haven't done anything at all to it (yet!)

 

[Rob_Feature]

And...sounds like someone is buying the 650 today...so I guess I'm settling in with a new 680 as my main receiver!

 

[SaturationPt]

I wondered about that, saw your ad and at $100 I was trying to justify a trip up to motor city, ... a lot of music for the money.

The 680 is a good receiver, better than "settling" for sure.

I have a neighbor with a 650 (since new), I do like how his SX-650 sounds, but I haven't had the pleasure of A/Bing it with a 680.

 

[Rob_Feature]

I listened to the two models pretty close together...and maybe it's because I'm so used to the 650, or maybe it's something else...but my ears IMMEDIATELY registered the difference with the 680. So much richer, less muddy, with beautiful round low end. Hopefully it won't crap out in a month after I sold the 650 regardless, I think I prefer it over the 650.

 

[SaturationPt]

I've compared the 1250/1280 and the 1050/1080 and can't say that there is a LOT of difference to my ears, but I did eventually pick a favorite.

For there to be that much difference between them in the 6xx I don't know if it is a design difference or just condition, have to trust your ears.

 

[Rob_Feature]

Yeah, I'm betting a lot of it is condition...but the weird thing is: The 650 was fully cleaned and recapped last year, so that one SHOULD sound better. But regardless...my ears say the thrifter won this contest.

 

[Dave Susek]

X2x series 1972-1974 (424-525-626-727-828) All Discrete, 1st series of the Silver faced Pioneers
X3X series 1974-1976 (434-535-636-737-838-939-1010) Discrete with a few IC's. Developmentally improved from x2x series
X50 Series 1976-1978 (450 to 1050) Redesigned all Silver faced, More IC chips, Mostly All Discrete output's
X80 Series 1978-1980.(580 to 1980) Slight layout improvement, More IC Chips. Lower end of the series used STK Modules for output sections.

Read the "PIONEER Equipment Database" STICKIES by Dr. Strangelove http://audiokarma.org/forums/index.php?forums/pioneer-equipment-database.126/

Got my first Pioneer a rescue from a recycle center 2 days ago this is great information.