B&K ST-140 amplifier buying decision


I have heard good things about this old amplifier. I like lush sound and read this amp fits the bill. Is it that good? Is it worth to pay $300 for it?

I have read there are two versions of this amp. I believe the one I put links below is the first/“better” version. Can someone confirm?

I don’t see any serial or tag on the back but it is old, so it is fine. I doubt it is something else inside :)

It is in working condition but probably would need to be recapped soon. So, that’s another cost. I do want to try this type old amps but then I am not that handy when it comes to fixing this type of stuff. Can do some fixing but not enough. 

https://ibb.co/GCSSsjf
https://ibb.co/pQ9ztym
https://ibb.co/Cw4dp8g
https://ibb.co/NtpKJ1B
celo
Admins: Can you please fix the & sign in the subject line. I wrote B&K but it shows gibberish!
These are really fine amps that have a mosfet output stage and sound very tube like. I have owned several, buying the newer model first and building a very good system around it as the power, it had 105 watts a side and a removeable power cord and I still own it. The earlier models, bought 2 used, were 70 watts a side and their power cords were hardwired in. Out of the 3 I believe the newer latter model was the better of 3. $300.00 seems high for one on the used marked but if it has been reworked might be a steal. Enjoy the music
I owned the early version of the 140 with 70 watts a side, it was a great amp, slightly warm/tube sounding but not mushy.  I Agee with tooblue, $3-400 already recapped would be fine. It is 20+ years old easily if not 30, and B&K went out of business a long time ago.
Plan to buy a 2nd one for spare parts if you fall in love with the amp. Boards are long gone.
Owned many B&K amps and preamps 20+Yrs, and sold the last three and two for scrap parts.
$300 seems a tad high, but it’s not like there’s that much room to come down from that price.
While a pretty nice sounding amp considering the price point, they are not at all suited for use with speakers with with low minimum impedances.
I’ve owned several of these - all of them the 105 watt versions. If that’s the 70 version in pristine condition it may be worth a little more, but if not it should sell for $150-$200 if it’s in excellent condition.
Well made, very  nice sounding amp.  $300 isn't a steal, but I doubt you'll find better for that price.  That amp caused quite a stir when it came onto the scene.  I picked one up for my son recently, and was thrilled to find it.
i believe the earlier version of the st140 had a blue/red B&K logo and the later one had a gold logo. i used to own the later (gold) version and it was a nice amp--warm and full-sounding-though slightly grainy and not the most transparent. overall i preferred comparably-priced parasound hca, and as per the above i'd think $300 is a tad rich.

Thank you guys! I Iearned more about it after your posts. I think I will get it but need to work on the price.


I have read more on the Stereophile link and noticed Sam Tellig talking about Eagle 2 which I have never heard. I looked into it and come to find out there is a strange story about the designer, John Gordon Iverson, of that amp!


Read it here:


https://charleyproject.org/case/john-gordon-iverson


I had an original ST-140 in the 1980's, and now own an Eagle 2A. The two amps have different sonic signatures, the B & K the slightly diffused/soft "mosfet-mist" character, the Eagle more focused and transparent, with particularly good bass reproduction.

Iverson disappeared off the face of the Earth one day, never to be seen again. Legend had it he was working on something that drew the attention of the FBI and CIA!
I owned the first version and it was a nice little amp; very much enjoyed it. At the time had hybrid Apogee Centaur speakers with a ModWright SWL 9.0 SE with all Clear Days cables… Kimber power cords except on the amp. Was a very nice modest system. Mine was pristine and gave it to a cousin. I bought it used I recall for $120 but that was probably 7+ years ago. I moved to an ARC 100.2 which was a far superior amp but it should be for an amp used is around $1700. I’d shoot for $200 and see if you can cap it at $250. Very clean simple amp and I’d be surprised if the caps need replaced… I bet they’re fine even for it’s age. 
I own one, purchased new in 1985. Had the toroid tranny. Owned it for 25 years. Sold it here on AG for $225 10years ago. 
I own one, purchased new in 1985. Had the toroid tranny. Owned it for 25 years. Sold it here on AG for $225 10years ago. 
I also have owned several Eagle 2 models. I still own a 2C prime (the last one ever made - says so right on the serial #plate). Much better amp, especially if you get the Eagle 2c prime, or Eagle 4 versions. They will likely need recapping too, and will cost more than the st140. There are some Eagle 2’s listed on eBay that are very overpriced (and not selling).
The B&K ST140 had at least 7 different versions I believe, 3 black with silver handles (70 wpc, 105 wpc, 105 wpc w/ toroidal transformer) and the black with black handles with red lettering. And then silver lettering without handles and one with red lettering with no handles.  All were 105 wpc, except for the earliest version which was 70 wpc.  There was also the 70 wpc version with a push button power switch instead of the rocker switch which was the earliest 70 wpc version. 

Over the years, I had 2 of them, both silver lettering, 1 with handles, 1 without.  I prefer the earlier versions maybe because I’m an old head :)