Oliver B120 Help?

Chuck_G · #1 08-11-2011, 07:57 AM

So, I won an Oliver B120 on eBay last week! That's the good news. The bad news is that it's in pretty rough shape right now. It powers up but won't make a sound - and it looks like a previous owner did some questionable "modifications" to the speaker connections. I'm not especially worried about the electronics - I have a great amp tech who worked on my SB-12 a few months ago.

However... a previous owner also cut pretty rough holes in the back panel to accommodate some extra(?) 1/4" jacks. The jacks themselves aren't connected to anything, and I'm thinking of doing a real refurb to the amp, including making a new back panel, and maybe re-covering the whole thing.

So, for starters- does anyone have a picture of the back panel of a B120 in good shape? Were there supposed to be any 1/4" jacks there in the first place?

The seller of the amp had a bunch of detailed pictures of the Oliver in the eBay ad, and he said he'd send them to me; I can post them when I get them.

Thanks!

bongomania · #2 08-11-2011, 08:34 AM

Man, it's too bad Jess passed away recently, he was super helpful about his amps right up to the end.

Phendyr_Loon · #3 08-11-2011, 11:07 AM

I owned a B 120 for a while. The only mods that it underwent during my ownership were a 3 prong power cord in place of the frail original 2 prong and I had a effects loop added. I don't know if the loop was a common mod but it might account for the random added 1/4" jacks on the back of your amp.

Are there any small holes in the grill cloth? Is the original speaker still in there?

Chuck_G · #4 08-11-2011, 12:37 PM

Quote:

Originally Posted by Phendyr_Loon

Are there any small holes in the grill cloth? Is the original speaker still in there?

Actually, grill cloth is in pretty good shape. Not sure if it's the original speaker. There's no label on it, but it has "28-67-003" and "67-7109" stamped on it.

...I'll get on uploading some photos.

Thanks!

Chuck_G · #5 08-11-2011, 01:06 PM

Here's the speaker:

Chuck_G · #6 08-11-2011, 01:07 PM

...and the chassis:

Chuck_G · #7 08-12-2011, 05:37 PM

...Anyone know anything? Is there supposed to be a line out or anything?

pgk · #8 08-12-2011, 06:04 PM

Quote:

Originally Posted by Chuck_G

...Anyone know anything? Is there supposed to be a line out or anything?

well from what i see they're just extra chassis holes, some covered by caps. my oliver b200 chassis looks exactly like yours and has those same extra holes. but it looks like someone removed the rectifier tube socket on yours and replaced it with a solid state recifier. my amp has a pair of 6L6's, gz34 rectifier and three preamp tubes, not two like yours. no line out, just two speaker jacks and that's it. looking at the back of my amp the one furthest to the right is the loudest and punchier of the two for sure, so maybe they're hooked up differently than a typical fender style head. hope this helps and good luck!

Vintage-Blue · #9 08-12-2011, 07:39 PM

I know you said you had a good amp tech but maybe this will be of use. It's the only B-120 info I have.

Oliver B-120 Schematic

Phendyr_Loon · #10 08-12-2011, 08:03 PM

The speaker connection to the chassis of mine, which I believed to be original, was a single RCA jack it was center positive from what I could remember.
From that photo it looks like someone did a hack job on the speaker connection.

Chuck_G · #11 08-13-2011, 09:58 PM

Thanks for the info, pgk, Vintage-Blue, and Phendyr_Loon!

Here's the back panel of the amp:

...Anyone know if that's the appropriate number of holes? The 1/4" jacks aren't connected to anything...

Thanks!

BassmanPaul · #12 08-14-2011, 11:43 AM

The more I look at this the more I come to the conclusion that this is an amp cobbled together from bits of other amps. the cabinet has a reverb tank and wiring, taped down, but no RCA jacks to connect it to. Even if there were there's not enough tubes for the driver/recovery circuits. I'll bet there were no phone jacks on the amp originally.

KramerBassFan · #13 08-14-2011, 12:15 PM

Quote:

Originally Posted by BassmanPaul

The more I look at this the more I come to the conclusion that this is an amp cobbled together from bits of other amps. the cabinet has a reverb tank and wiring, taped down, but no RCA jacks to connect it to. Even if there were there's not enough tubes for the driver/recovery circuits. I'll bet there were no phone jacks on the amp originally.

So its not just me?

My first glance at that piece of equipment made me think "what a thrown together piece of junk!"

I'd imagine Mr. Oliver would have hated to see some of his equipment in such a state.

It's got potential certainly, don't get me wrong. But that thing has seen one too many a hack saw and soldering iron.

Get that bad boy all cleaned up and working great.

beans-on-toast · #14 08-14-2011, 03:55 PM

The so called uniflex design was a combo. I don't believe that any of the 1/4" jacks or the holes were original. The wiring from the speaker to the amp would have been internal.

The amp did not come with the spring reverb so that was added. Perhaps someone modified the amp by adding a driver and recovery stage. You can check the circuit against the schematic that Mark posted.

Here is the user's manual for the B120. The amp was 35W RMS and listed for $269. It was available with an optional Altec Lansing speaker (model: B120A) the price was $389. The dolly was optional at $17, as was a black vinyl cover for $13.

Chuck_G · #15 08-14-2011, 06:16 PM

Thanks, BassmanPaul, KramerBassFan and Beans-on-Toast for the replies and additional info. Yeah, I was sort of wondering if that was a reverb tank, and I didn't figure that any of those holes in the back were original. I did know that the cabinet is original, and the amp came with the dolly attached.

I'm probably going to take my time on this and do it right. As I see it, it's not like I'm going to take the thing out on a gig tonight, anyway. And I have to admit a little sentimental/nostalgic value here: back when I was at Berklee, my teacher had one in his studio (not sure if they were in every studio or bass classroom...) so I know that a good B120 is a terrific-sounding amp.

I mentioned my amp tech - I use Stan Dey - and he's not only excellent, prompt, and reasonably-priced, but he's great about talking shop, so I can discuss "fixing" vs. "restoring" the amp with him, and I'm sure he'd be open to whatever. Also, my father is a handyman, and I think he'd helping with re-tolexing the cabinet.

Thanks again the input, everyone!

Wannabass · #16 08-14-2011, 06:51 PM

Hey chuck, mine was missing the back cover when I got it and the speaker was shot. I was lucky enough to have Jess go thru it while he was still here. He left the original two pronger on there..
Let me know if you find any detail on the back cover. I am pretty sure it should be flush with the back speaker cover.