Official Ampeg Portaflex Club

Discussion in 'Amps and Cabs [BG]' started by JimmyM, May 25, 2008.


  1. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    I haven’t. The system says he was last logged in January 29, 2018.

    I hope that he is well.
     
    lowplaces likes this.
  2. earache60

    earache60

    Apr 16, 2018
    Wow you guys are extremely helpful - and fast!
    Thanks for all the info!

    Do people usually wire around the speaker/latch connection or do they keep it that way?
     
  3. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    People do the speaker connection both ways. It comes down to personal taste and if you want to keep the amp all original or not.

    Personally, the latches can be a weak link. The latch can oxidize and loosen, risking the amp. If you keep it that way, make sure that it is checked once in a while just to make sure that all is well. Later revisions did not use the latches to make a connection, they used a connector.

    You might find the attached file of value. It's for an earlier revision.
     

    Attached Files:

    JoeWPgh likes this.
  4. JimmyM

    JimmyM

    Apr 11, 2005
    Apopka, FL
    Endorsing: Yamaha, Ampeg, Line 6, EMG
    I've seen them go about half and half. Some love the kitschy way of connecting it, some hate it and install regular 1/4" jacks. I would definitely run that by your client.
     
  5. el murdoque

    el murdoque

    Mar 10, 2013
    Germany
    The PF20/50T have dropped in price over here in Germany. Thomann lists the 50 at €899 (was 999) and the 20 at €559 (was 699) now - in fact, all the major (online) shops do.

    Any specualtions why that may be?
     
    JimmyM likes this.
  6. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    In the US and Canada there is a $100 rebate for a limited time. They do this a couple of times a year during periods when sales are typically slow and they want to boost their quarterly profit. Maybe the reductions in Europe are instead of a coupon sale.

    Prices sometime drop due to competition. The market sets how much they can charge.

    The question is, are the prices permanent or time limited.
     
  7. BLDavis

    BLDavis Master of Snarks. Gold Supporting Member

    May 21, 2009
    Ellenboro, NC
    Can I get in?
    029.jpg
     
  8. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    The amp fits right in there with Americana and Bluegrass music.

    It looks like a double baffle cabinet, very good condition. Do you have a date of manufacture?
     
  9. BLDavis

    BLDavis Master of Snarks. Gold Supporting Member

    May 21, 2009
    Ellenboro, NC
    The serial # puts it in 1962/63. Sounds like an angel having an orgasm.
     
    mnats, lowplaces, JimmyM and 2 others like this.
  10. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    62 to early 63 used the 5u4GB tube rectifier. Later ‘63 had a solid state rectifier, only five tubes. Early ‘64 used a 5AR4 rectifier. The best way to tell is to look at the pot codes inside the chassis. 137 followed by year and week.

    Good characterization of the heavenly sound.
     
  11. JimmyM

    JimmyM

    Apr 11, 2005
    Apopka, FL
    Endorsing: Yamaha, Ampeg, Line 6, EMG
    #646 BLDavis

    Looks to be in pretty decent shape, too. Nice!
     
  12. BLDavis

    BLDavis Master of Snarks. Gold Supporting Member

    May 21, 2009
    Ellenboro, NC
    Thanks B-O-T and Jimmy,
    It's in great shape for 55 years old. A lot better than I am at 55y/o. Missing the dolly but a previous owner attached casters directly to the bottom. Someone had installed metal door handles on the side that looked like ass so I replaced them with leather handles from Fliptops.com. Still has the kick stand though. I had my tech re-tube it and replaced the caps and install a grounded a/c cord.
    B.
     
  13. Backbeat

    Backbeat Supporting Member

    Nov 15, 2011
    Hello Everyone,
    I'm really new to posting, so bare with me.
    My pursuit of a B15 has been long and uncertain. But I have always read this thread, because the amp is...
    So beautiful! Looks and sound!
    The people involved here are quite exceptional as well. Jimmy M, Beans On Toast, Vintage Blue et al.

    I have a '61 B15N, NRF. It's in really beautiful condition. I bought it last September. Finding it and buying it was luck. You guys have actually seen it before. I found a thread about it from 2010-11...?
    I'll post pics later when I'm home, but now I had a question...

    Today I was checking the self noise by turning up the volume on channel 1. At 3 o'clock it gets quite noisy, At about 5 o'clock, I start to hear a high pitch, and then it starts feeding back heavily. I quickly turn it down, and the channel cuts out. The channel cuts in and out a few times, then it's normal. It kind of behaves like a dirty pot. But when it's back to normal, there's no scratchiness in the pot at all! Now of course, I never play it turned up like that, but I feel like it's something that shouldn't be happening. Am I correct?
    Otherwise, it's really pretty quiet, and sounds so good!
    Channel 2 is really noisy, as well, when turned up, but it doesn't feed back.
    The amp was recapped, couple new power tubes, and a 3 prong power cord.
    Just a great thread! Many thanks.
     
    cazclocker, beans-on-toast and JimmyM like this.
  14. JimmyM

    JimmyM

    Apr 11, 2005
    Apopka, FL
    Endorsing: Yamaha, Ampeg, Line 6, EMG
    #647 Backbeat

    Thx for the nice words and welcome to the cul...er...club! It's normal to hear more noise, as turning up the volume also turns up the noise floor. Feedback, however, is not what you're supposed to hear. My first thought is a microphonic preamp tube. Could be wrong, but that what it sounds like to me. But Beans is really the amp expert and he knows way more about the inner workings than me, so wait for his second opinion before you go buy new tubes.
     
  15. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008

    No you shouldn’t have any feedback when the amp is turned up.

    There isn’t a magic answer as to why this is happening. It’s something that’s best resolved by a tech. But any issues can be fixed.

    It could be:
    a bad preamp tube,
    a bad shielded wire in the preamp,
    the layout of the wires,
    a microphonic component such as a capacitor.

    The oscillation could lie in the preamp or the in the power amp. Try isolating it to one or the other. You can send the preamp out via the Ext Amp jack to another amp and see if the oscillation is inthe preamp. Likewise, you can fee a preamp signal from another amp into the power amp via the Ext Amp jack.

    To tackle the noise, the tube socket contacts should be scrubbed with deoxit. The sockets should be retensiond if necessary. The ground points to the chassis need to be clean. Remove the jacks and the pots and check for oxidation. If there is any, use deoxit. The solder joints may need to be reflowed. Old resistors can get noisy. The tone circuits are another possibility.

    Basically the circuits need to be gone over with a fine toothed comb. Everything needs to be checked. All this sounds more complicated than it really is, it just takes a bit of time.
     
  16. Backbeat

    Backbeat Supporting Member

    Nov 15, 2011
    Thank you Jimmy M and Beans On Toast. I’m going to drop it off with a tech in the next couple of days. I have to admit, I wish I could just send it to you Beans. :)
    Just to be clear. I never get feedback, or the high pitch when I’m playing. It only occurs when I turn the volume up to max, with nothing plugged in. Otherwise it sounds great, and is pretty quiet.

    This amp was the 82nd unit made in Dec 1961.
     

    Attached Files:

  17. JimmyM

    JimmyM

    Apr 11, 2005
    Apopka, FL
    Endorsing: Yamaha, Ampeg, Line 6, EMG
    Dang...just dang!
     
  18. beans-on-toast

    beans-on-toast Supporting Member

    Aug 7, 2008
    I don’t know if I’ve ever seen a cleaner example of a ‘61. Wow, congratulations!

    I recall seeing a Barney that was posed with a B-18.
     
    JimmyM likes this.
  19. Backbeat

    Backbeat Supporting Member

    Nov 15, 2011
    You are correct. I searched and found a short thread from the guy I bought it from. He mentioned it to me. It’s a bit of a story.
     
  20. Backbeat

    Backbeat Supporting Member

    Nov 15, 2011
    Does media gallery embed upload my photos? I'm a little confused by the options. Looking for the easiest way.
    I'd like to show you all some pics of the amp. I know I like to look at others amps and guitars. Figured you might like it too.
     
    spellcaster, JimmyM, JoeWPgh and 3 others like this.
  21. Primary

    Primary TB Assistant

    Here are some related products that TB members are talking about. Clicking on a product will take you to TB’s partner, Primary, where you can find links to TB discussions about these products.

     
    Jun 13, 2021

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