Those 3 guys could answer pretty much ANY question regarding vintage (and current, for that matter) Ampeg stuff. A wealth of knowledge there for sure!!
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Official Ampeg Portaflex Club
- Thread starter JimmyM
- Start date
I've seen some videos from bands using loop-stations in the late 70's, but back then, seen that live, may let you thinking in some sort of alchemy going on stage.
I use Boos RC20XL and Line 6 delay.
Back in the 70's their loops were probably tape based.
Enjoyed the performance! Both products look interesting. A couple of nice things to bump up to the top of my list.
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The 70's cabs are bigger and weigh more. If the problem is the standby switch, you might be able to use a tool to set the switch so that it would work.
NAMM is coming up at end of January, you never know what'll be offered.
Hi folks,
I would like to know what's your opinion or experience with alnico speakers in bass, a couple of months ago I grabbed a NOS Hi-Fi Jensen Alnico that I wanted to try in my SB-12, so far my thoughts are that those speakers are very sensitive and responsive with highs, they behave "well" with mids but not with highs and lows, I simply don't feel they perform naturally with this amp, the fact that I need to tweak the amp and controls in the bass just doesn't feel right, if I compare it to the installed JBL-D123, no matter how I set the knobs in the amp and bass feel that I can dig into different bass styles, now I'm putting my eyes in the B15n to try a JBL, so going back to my initial question what was the ampeg approach in choosing alnico speakers in bass amps.
I would like to know what's your opinion or experience with alnico speakers in bass, a couple of months ago I grabbed a NOS Hi-Fi Jensen Alnico that I wanted to try in my SB-12, so far my thoughts are that those speakers are very sensitive and responsive with highs, they behave "well" with mids but not with highs and lows, I simply don't feel they perform naturally with this amp, the fact that I need to tweak the amp and controls in the bass just doesn't feel right, if I compare it to the installed JBL-D123, no matter how I set the knobs in the amp and bass feel that I can dig into different bass styles, now I'm putting my eyes in the B15n to try a JBL, so going back to my initial question what was the ampeg approach in choosing alnico speakers in bass amps.
So I figured I would say I have a 1964 Ampeg b18n restored by Jess Oliver in 2006. It sounds pretty damn good! If anybody is interested, it is also for sale. Just thought everybody would like to see it!!
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Ampeg used Jensen AlNiCo speakers in some of their early amps before ceramic was readily available. Once they moved to ceramic and didn't look back.
You shouldn't have to struggle to dial in a good tone with a speaker in an SB-12.
I find that Alnico and ceramic sounds a bit different from one another. Alnico speakers are known for their compression when pushed; they break up earlier and have a smoother distortion; ceramic speakers are cleaner and have more headroom. The magnets tend to be bigger on ceramic speakers. When you dig in, the alnico speaker will compress and possibly distort so that will affect the tone and you tend to want to compensate by adjusting the tone controls.
I use alnico speakers in guitar amps such as the '59 Bassman (410), VOX AC-30 (212), '59 Fender Deluxe (112) for the compression and distortion. If you don't want that in the SB-12, a ceramic would be better.
One problem with alnico speakers, is that if you drop them (some say driving them hard, rapid change in magnetic flux), they can loose some of their magnetization. Some old speakers do not perform up to spec. Some re-coners can renew the magnetic charge if this is an issue.
It looks like it's in very good shape. Obviously well cared for which is a plus. Good luck with the sale.
Guys,
Does anyone have any suggestions on what would be best to use to clean the grill cloth on my B15? I have an early 70's silver clothed cabinet and it has some brown staining around the edges. It looks like it's probably smoke stains from years of bar gigs -- but I'm just guessing.
Thanks in advance!
JC
Does anyone have any suggestions on what would be best to use to clean the grill cloth on my B15? I have an early 70's silver clothed cabinet and it has some brown staining around the edges. It looks like it's probably smoke stains from years of bar gigs -- but I'm just guessing.
Thanks in advance!
JC
Joel, there are some tips in the TB Portaflex Wiki.
It is most important to take a conservative approach. You can clean it without removing the grille cloth by dabbing cleaners. Too much water and the baffle can warp. If you want to do a more thorough job, it is best to remove the cloth, clean it, and then reinstall it. There also tends to be a buildup of dust under the cloth that should be cleaned. Some of this dust is decomposing foam that was installed on the baffle under the cloth. It is a good idea to install some felt in place of the foam. This helps prevent the cloth from flapping.
Doing this requires that you have a heavy duty stapler. Reinstalling a grille cloth is not as hard as installing a new one because the folds stay in the cloth. There are some details on installing a cloth on Roberto's SB-12 here. The SB-12 is a little different than that of the B-15 in that the cloth on the B-15 wraps around the baffle. But the stapling part is the same. Earlier in that section, the technique for removing the cloth is demonstrated.
If it doesn't clean well, you can always buy some replacement cloth from a place such as Invalid Link Removed.
David
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Hello all, I am writing to find out how to "join" the portaflex club. I just picked up a 1967 BT15 portaflex Illuminated face. Here are some pics. It is an awesome unit although it is SS, it still has quite a bit of balls-out tone! Missing the left side handle. Anyone know if they are made anywhere?
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Thanks David. I'll give it a try this weekend. If I can't get it clean I'll consider buying new grill cloth for it. I'll circle back and share the results.
I would be clueless about that, although Jess stated a preference for edge wound voice coils. I do know that my favorite SVT 810 speakers have usually been CTS alnicos, but I think the ceramic ones in the Heritage 810e are their equal for tone. They come across as very similar when I'm standing in front of both. And I know that many decisions of Everett Hull's had as much an eye on the bottom line as tone and performance. The stock speakers for both the B-12N and SB-12 were the Jensen C12N's, with JBL D120F's available as upgrades for both, and at different times, you could get the Jensen EM1202 or the Altec 417B as upgrades, although I'm pretty sure the Altec was for the later Unimusic SB-12's with the bigger cab.
So to sum up, I know nothing
Your amp is in great condition. Often the illuminated panel is broken on these amps so having one that works is a big plus.
It looks like your good handle is a replacement. All the ones that I've seen have had the same handle that is on the B-18 cabinets. The handles are sold by fliptops.net. There is another source: http://www.barefrigeration.com/Products/Kason-573-Offset-Pull-Handle.html. The Kason 573 can sometimes be found for a good price on ebay.
Well thank you for the handle info. This one is my first experience with the portaflex of this generation. I have played a few gigs with B15N Reissues as back line. This amp sounds louder than 50 watts, especially with the extension cabinet. The speaker is an Altec 421 and has such a resonant ampeg mid punch. I can't believe the pullout ultra high pots still work. I am seriously impressed with the tone of the amp. I am using this on top of my PF410HLF and it smokes the PF500 for the vibey tone. The sound is a bit fuzzy and has that vintage loud "pop" upon initial startup. Yet the cabinet doesn't rattle as much as expected. I tightened up all of the interior nuts on the cab and the speaker. Question- Is this the same design as the 1970 (last year?) I only question because I know the cab design is different and it is larger with a little more power output. I actually was told it was a 1970, so I was a little disappointed when I opened it and the board is hand written 22 NOV 67. But after playing through it for a few hours the sound has won me over. Also didn't the '70 have the ultra low and ultra hi black toggles?
There were revisions to the BT-15 amp. I'm not sure what years it was in production, although it was in the 71 catalog. The early version had the Hi-cut switch; the later (as seen in the 71 catalog in the PF Wiki) had ultra-hi and ultra-lo switches.
Your cabinet, with the double inlay in the front, is consistent with the 67 revision. I wouldn't just go by the 22 Nov 67 date on the circuit board. Circuit boards spanned years. A better indicator is to look at the codes stamped onto the pots. Look for one on the pot's metal case that starts with 137 (the CTS code), the date code follows. Look for any other parts with date codes on them to refine the date of manufacture.
An extension cab really makes the amp sound louder as you said. The Altec 421 was an option that costed more.
It is possible that the power supply caps need changing due to their age. Look for any swelling of the cans but a tech can test them. This could help with the fuzzy sound if it turns out that the caps are in rough shape.
Your cabinet, with the double inlay in the front, is consistent with the 67 revision. I wouldn't just go by the 22 Nov 67 date on the circuit board. Circuit boards spanned years. A better indicator is to look at the codes stamped onto the pots. Look for one on the pot's metal case that starts with 137 (the CTS code), the date code follows. Look for any other parts with date codes on them to refine the date of manufacture.
An extension cab really makes the amp sound louder as you said. The Altec 421 was an option that costed more.
It is possible that the power supply caps need changing due to their age. Look for any swelling of the cans but a tech can test them. This could help with the fuzzy sound if it turns out that the caps are in rough shape.
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