Jess Oliver's legacy - AMPEG PORTAFLEX CLUB part 10 - Page 17

Apex_speed · #**321** 02-08-2013, 08:35 PM

Quote:

Originally Posted by wessman

Hello,

Are your B15's dead quiet or they are making some constant pitched noise even though your guitar cable is not connected to the amp? Mine is dead quiet while on stand-by mode, but once stand-by switch is in a play mode it starts to make a constant pitched electrical noise . Many thanks for your replies.

BR yeppe

Ps very nice greeny amp 😎

They should have a VERY slight buzz to them and that is it. If it is on the original power supply caps, I would guess that could be a contributing issue. I assume you have tried the hum control already.

shadven · #**322** 02-08-2013, 08:37 PM

Quote:

Originally Posted by kuratacus

thanks....yeah, did all the tolex work myself... sticky job but someone has to do it. have a few other cabinets i recovered as well. and i did all the work on the upright (the tailpiece, finish flames etc...)

+2 Very cool. How did you do the flames on the upright? That is something I'd like to figure out. I am seeing tiki gods on mine

**Bass 45** · #**323** 02-08-2013, 08:55 PM

Quote:

Originally Posted by gjbassist

I dissembled the cabinet of my B-15T today to give it a thorough cleaning and replace a couple of broken parts. When I removed the speaker I noticed that it is 8 ohms instead of 4 ohms. All the info I can find on this amp says the EVM 15L speaker in the cabinet is 4 ohms. I find it a little hard to believe that someone would have replace the 4 ohm speaker with the exact same 8 ohm speaker. Is it possible that when it was built they used an 8 ohm speaker on a few of these amps?
Another thing I have noticed is the lack of the Portaflex nameplate under the Ampeg logo. Every image I have found of the B-15T has this. Mine doesn't even have holes where one could have been attached to the grill. I wonder if mine could have been a prototype or very early version of the B-15T?

I thought you might like to know there is an eighties catalog supplement for sale on Ebay for your B-15T.

http://www.ebay.com/itm/Vintage-Ampe...item43afa6235e

I have one of those brochures and it does indicate a four ohm EV in the specs. Does yours have a schematic printed on top? It is possible someone got a new 15L without knowing about the whole ohms thing.

gjbassist · #**324** 02-08-2013, 09:45 PM

Quote:

Originally Posted by Bass 45

I thought you might like to know there is an eighties catalog supplement for sale on Ebay for your B-15T.

http://www.ebay.com/itm/Vintage-Ampe...item43afa6235e

I have one of those brochures and it does indicate a four ohm EV in the specs. Does yours have a schematic printed on top? It is possible someone got a new 15L without knowing about the whole ohms thing.

That's cool! Thanks for the heads up! I just bought it. Hope it's in good shape.
Yes mine has a schematic on the top of the amp.

beans-on-toast · #**325** 02-08-2013, 09:52 PM

Quote:

Originally Posted by wessman

Are your B15's dead quiet or they are making some constant pitched noise even though your guitar cable is not connected to the amp? Mine is dead quiet while on stand-by mode, but once stand-by switch is in a play mode it starts to make a constant pitched electrical noise . Many thanks for your replies.

On standby, only the tube heaters are on, the amp is not fully turned on so it should be very quiet. Turn it off standby and the amp powers up. Off standby it should be quiet as well though.

We need to identify what kind of noise it is. There are many possibilities. Is it a 60Hz hum? Is it a higher pitched hiss? Does it sound like feedback?

beans-on-toast · #**326** 02-08-2013, 09:55 PM

Quote:

Originally Posted by gjbassist

Yes mine has a schematic on the top of the amp.

Does the schematic indicate how many ohms the speaker is supposed to be?

Despite what the label on the speaker says, if you can you should test it with an ohm meter to see if it is really 8 or 4 ohms. Do this with the speaker disconnected from the cab.

It is possible that someone replaced the speaker and installed one with the wrong impedance.

portaflexer · #**327** 02-09-2013, 09:39 AM

This is not directly portaflex related, but I though one of you Ampeggers might have an idea on this one...

http://www.talkbass.com/forum/f15/wh...c-417as-956747

kuratacus · #**328** 02-10-2013, 11:08 AM

Quote:

Originally Posted by shadven

+2 Very cool. How did you do the flames on the upright? That is something I'd like to figure out. I am seeing tiki gods on mine

the flames are done with a matt finish with gloss flames over top. for me it was stain and tung oil, then i masked the flames and did 2 very light coats of poly urethane. OR you could sand the lightly surface down to get a satin finish then apply the flames

shadven · #**329** 02-10-2013, 03:21 PM

Uh-Oh, looky what I just brought home! I haven't dated it yet, but it's in very good shape, I think it's the original cage and tolex, no dolly, and the speaker looks like it was replaced. $950. Sounds great! What is the best site to go for for dating via s/n (056629)? It looks like it's a 1967 SB-12.

portaflexer · #**330** 02-10-2013, 04:31 PM

This was the numbering system they used in those days...

000001 - 020000 = 1965
020001 - 049000 = 1966
049001 - 075000 = 1967
075001 - 080000 = 1968
080001 - 092000 = 1969

Based on those number, you are correct. However, its usually best to determine the date by pulling an EIA code off an internal component (pot, cap, etc).

JimmyM · #**331** 02-10-2013, 04:38 PM

Pretty cool. When I get too old to lug a B-15, I'll be getting me one of them.

Aussie Mark · #**332** 02-10-2013, 05:09 PM

^^^^
That SB-12 looks in great condition. Nice score! My SB-12 is much loved by recording engineers when I bring it to a session.

beans-on-toast · #**333** 02-10-2013, 05:32 PM

For those interested, here is a copy of the SB-12 user's manual.

shadven · #**334** 02-10-2013, 05:54 PM

Quote:

Originally Posted by beans-on-toast

For those interested, here is a copy of the SB-12 user's manual.

Thanks!

spacebassed · #**335** 02-10-2013, 08:21 PM

Anyone here snag that '60 B15??? It went for $736.27.

JimmyM · #**336** 02-10-2013, 08:30 PM

Quote:

Originally Posted by spacebassed

Anyone here snag that '60 B15??? It went for $736.27.

Gotta be kidding! I guess I better start watching Ebay more often.

fuzzy beard · #**337** 02-10-2013, 08:38 PM

I dont think it is a 67. Speaker connection through latchs was only done in 65 and 66. If it is a 67 it would have to be very early!

Also i thought 67 was the first year of the ext speaker out on the sb-12.

shadven · #**338** 02-10-2013, 09:34 PM

The s/n seems to indicate early '67. The speaker definitely connects through the latches.

kuratacus · #**339** 02-10-2013, 10:33 PM

Quote:

Originally Posted by JimmyM

Gotta be kidding! I guess I better start watching Ebay more often.

it was just the head and in pretty rough shape.

**ddbassGA** · #**340** 02-10-2013, 11:20 PM

Quote:

Originally Posted by spacebassed

Anyone here snag that '60 B15??? It went for $736.27.

I watched that auction. Very tempted but....

There are 3 complete double baffle-era B-15Ns on there now...a sweet NRF one, a '64, and a '61 with pilot light that was retolexed with blue check! ouch.