Ampeg B-15N Portaflex

Purchased new in 1973 for doing small to medium rooms. Used it with a Fender P bass for pop, blues, and jazz. Though rated at a modest 30 watts it has produced plenty of deep, warm, thunder. However, the original 15" Ampeg speaker didn't produce the crisp definition on the high-end to suit my taste even when the ultra high/low tip switches were enabled in hopes of deriving the hoped for result.

To obtain the enhancement I was after I purchased an 8-ohm Fender Professional PS-15 in 75'from my dealer source which gave me a 3"VC, and an 8-10 lb. magnet. Whatever, it added another 22-lbs to the overall unit. It produced the upper response i had hoped for while preserving, and even enhancing the depth on the lower end. If memory serves, I believe JBL produced the PS-15 for Fender using one the D-120 or 130F. I remember paying somewhere around $120 for the PS-15 at the time which was pricey for a speaker in the mid-70's, so it may have been a JBL. Maybe one of you other Ampeg/Fender afficionados might be able to confirm. The speaker is still in the cabinet and being used presently on a weekly basis. I alternately use the 'normal' inputs of both channel 'one' and channel 'two' just to keep the jacks abraded and active.

Presently, I'm using an Ibanez Soundgear SR400 with a set of DR 'High Beams' .40 - 100 with the B-15N, and for my audio taste in quality bass response, and those of our quartet, the sound is absolutely dynamite. Popping and slapping sound delivery is no problem. Although the B-15 has only two basic basic tone control knobs for bass and treble, and no mid-range, I find setting the B & T at 70%
and "contouring" with the actve electronics on the axe,
gives the mix I enjoy using for just about all the type music played. The pickups on the 400 are P & J. I always use the 'J' and finger pick right over top that soapbar. Volume on the B-15 itself has never gone beyond 40& so I can't comment on any distortion problems.I don't believe in "pushing" any electronics regardless of its purported excellence. I set the 'gain' on the bass at 80-100% which gives me plenty of clean, distortion-free bass balls! I've heard nothing in a medium-sized combo that can hold a candle to the portaflex.

The B15N has been totally reliable. I purchased a set of backup tubes for it at the time I bought it. Replaced 'one' 5AR4 in twenty years of on/off use. So reliable never had need for a backup. I did replace the original bluish grill cloth which had been color mutilated with/by tobacco smoke tar. Used a black semi-transparent replacement speaker cloth for aesthetic, and apparent purposes
.

Fortunately, the occasion never arose where service was required. There was an authorized Ampeg Service Repair in the area up until the 80's, and it vanished. The fellow doing the work retired and folded up Shop. Now the question arises as to where or whom can you send your powerhead if electonic repair servicing is required? Who knows AMPEG circuitry and is as reliable as the product itself?

Have been playing on and off over the years since the early 70's. Have a Yorkville KB100 I use for both keyboard or bass which is also highly reliable and sonically excellent for an amp half the weight and size of the B15N.
Doubt I'd want to spend $1600 for a new portaflex which is even heavier than the B15. Getting too old for that crap.
Would probably settle for the Ampeg Rocket Bass 50 if it came right down having to replace a stolen B15.
The B15N has a sound which is very difficult to imitate even with todays advancements in audio engineering. I have not heard anything so far that equals it except for Ampeg's solid state Rocket Bass.
For outright no gimmick bass playing, all the B15N requires (given a good bass guitar with active electronics), is one normal input, vol. treble, bass controls, and top of the line Eminence B15-8 or JBL's newest E-series 15".
My B15N with the PS-15 speaker, and dolly weighs in at 97 lbs. Ugggggh. Worth every pound, though!

This amp was made in 1965 I purchased it new , the small music store whre I got it let me try out several amps in actual gigs,including Fender Bassman which I and the band thought was good, but when we put them side by side there was no comparason!! the B 15N was the one.
will not repeat specs. they are same as other threads here

I play a 1965 Fender P bass I have used this setup sence new in country music, still sounds great, I'm sure this rig helped me get some jobs I wouldn't have gotten otherwise, it has what I call the "Big Foot" sound with the 15" JBL speaker it fills the room to the very back.

Use this amp without back up today on small gigs( plug directly into PA on larger ones) about 5 years ago it started blowing fuses, power transformer was bad, was repaired with new part from ampeg, have changed power tubes once, still have origonals as couldn't see much improvement with new ones! I have taken very good care of amp. still looks new. the origonal cover is getting a little tattered.

Have not dealt with the company but was able to get parts (just takes money, you know how that is!)by the way Ampeg has repoduced this amp in the B 15R, I have a catalog from Musicians friend listing it for just over $1500 with retail around $2300!!!

Have been playing since the 60s am retired from my day job, I play a lot of senior dances Jam sessions county fairs, nursing homes etc. lots of volunteer stuff, just having fun now!
I also play guitar and sing, I have a Gretsch country gent, that play thru an old Kustom 150 or a crate ca 125, also just pruchased a Washburn Cumberland acoustic electric, I like it!!!

early 60's b/15 no frills amp now sits at home as a practice amp
i have to admit it still sounds good in a low volume situation
but it can't cut it on a loud gig, but i still use it for trio gigs.it is heavy and i'm getting older

i use a p/bass + play lounge style jazz and older style r+b. it has
a good solid basic bass tone.the amp is quiet and has a ground switch and a hum control to control unwanted noise. although the b/15 is small it can fill a room

i've had this amp since 1964 w/o any breakdowns. i change the big tubes but it still has the original pre tubes. i never take a backup amp.

i know ampeg is still in business but this model has been out of production for quite some time and i assume none of the "old timers" are there anymore

i have been playing since the 60's i also use a sunn bassamp.
if something happend i would like another one but they are not around like they use to be. i like the sound and the flip/top and the dolly roller for moving it around. i compared it to a fender bassamp which was a good amp but not as portable as a b/15

this has got to be one of the first...date of manufacture...1960
standard for this year was a 12" speaker with an optional 15"...it has three channels...guitar, bass, inst. volume, treble, and base controls...are split between two channels. no effects, actually no reverb...that came in 1964...I think...obviously all tube...I believe it runs at 30 watts...great for breacking up lead guitar licks...how I use it mostly....the bass is played through it occasionally...surprisingly both can be played together without appreciable loss...

I play an ibenez gax 70 through it using a boss me-5it will go totally sonic or smooth jazz...the feedback is smooth like paddling a canoe...it's great...bypassed it breaks up perfect for hard blues licks...it can be cranked up to ten if your carefull...carving surf nazis rule...

I would take it anywhere it is the best studio amp alive...it has blown the preamp cap twice once in 1967...and again in the early ninties...top flips down and it rolls away....

I took it to the local amp nazi.....I had to pretend I didn't know what it was to get him to work on it...he replaced the burnt cap and a resistor for $32.oo

I have had this amp for nine years....I got a steal on it from a pawn shop with the cap blown...I needed it for the seperate guitar and bass channels for a gig that weekend...honestly I didn't know what I got until my brother looked it up on e-bay...they were going for between $500.00 and $900.00 depending on condition... I work with two studios...currently I am setting up a small studio with my son...and will look for another on the net to fill in on bass....although I doubt I will ever be able to afford a 1960 again....p.s. this is the only blind luck this nigger has ever had....

This amp was made in 1969 by Ampeg. When I bought the amp, it did not have the original speaker, but I managed source out a 1971 speaker out of a B15S for it(Lucky!). The tubes are all original. The amp contains 2 6L6GC's, 3 6SL7's, and a 5AR4. It puts out roughly thirty watts, but compared to what you get from amps today, I'd say it probably has the volume of a 60-70 watt amp. The amp has 2 channels with 2 inputs in each (bright and normal). Each channel has a Volume, Treble and Bass, with an Ultra high, and Ultra low switch. Not by any means a lot of features, but the variety of sounds it produces more than compensates. It is truly versatile despite the lack of features. It does however have an extension speaker out, and an extension amp out. I feel that it deserves at least an 8. It is hard to compare it's features to todays amps. I feel it is probably one of the best if not THE best combo you can get.

I play with a Fender American Series precision bass with 1967 "grey" pickups(fender), and I have 2 Uprights with David Gage "Realist" pickups. I play mostly Jazz and blues, so the amp suits my style perfectly. It is the smoothest sounding amp I have ever heard, yet retains clarity. It is very deep sounding with the Precision, and is incredibly loud for it's wattage. It produces the warmest sound I have ever heard with all three of my basses. It is the best sounding amp I have ever had...heard...or played! And, amp has next to no hum unless you stand right over top of it. The amp distorts when you turn the volume just past 2/3rds, but the tubes are old, and I am replacing them with new Sovteks. This amp deserves an 11!

This amp has played perfectly for over 30 years according to it's previous owner, and I haven't had a problem. I'd gig without a backup.
Still, you've got to be careful with it. It has endured the test of time, I give it a 10.

I have been playing for a few years now, and it's the best amp I've ever owned. I own an Ashdown C110, and an SWR Baby Blue II, and it blows them both away. It doesn't have the power of the Ashdown, or the flexability of the SWR, but it sounds better than both of them!
It is deep, smooth, clear. It is the perfect bass combo.

The amp in question is an original 1966 Ampeg Portaflex Model B-15N (f), the "f" standing for the "f" circuit. It sports the blue check Tolex covering. It's an all tube amp, which uses three 6SL7's, two 6L6GC's, and one 5AR4. Three inputs, and two channels. Channel one has a "Guitar" and a "Bass" input, and channel two has an "instrument" input. Each channel has a volume control and a Treble and Bass control. Front panel also has a standby switch, ground reverse switch, and a on/off switch. Rear panel has hard wired output to integral speaker cabinet (I'll talk more about this later), AC plug, 8 OHM EXT. speaker output, EXT. Amp output, and hum control. The amp head clamps down to the speaker cabinet, and can be unclamped, flipped over, and clamped again, so the amp head is stored within the speaker cabinet. Light up plexi "ampeg" plate on the tube cage which acts as an on/off light. There is no channel switching. Not a lot of features by today's standards, but what more do you need? Personally, amps with a hundred knobs drive me nuts. The two tone knobs may appear limiting at first, but with just these two knobs, you can achieve a wide spectrum of sounds, from the lowest bassy blur to a crisp thin clanky high. The speaker cabinet has a 15 inch Ampeg Custom Design speaker with square magnet.

The Ampeg B-15N is a legendary amp, and with good reason. Without a doubt, this amp creates the finest bass tone I have ever heard. I've been playing bass for 20 years, and recording for 15, and never have I encountered an amp that shaped my sound in such an indispensible way. Before I picked up the B-15, I used to play bass, and amplify it with an amp. The B-15 adds so much to my sound, I feel as if I'm playing the amp as much as the guitar. I use two Rickenbackers (4001 and 4003), and even with these classicaly clanky basses, the Portaflex sounds warm, smooth and creamy. As I said earlier, this amp is capable of creating high endy clanky tones, but it's not really where it excels. The strong suit for this puppy, is warm, rolling, smooth, rounded, buttery, creamy, rich, crushed velvet,...well, you get the idea. The amazing thing is that the tone remains completely focused even with all the smoothness. You really have to hear one of these guys to understand what I'm talking about. As boring a proposition as practicing the bass alone can be, I often find myself playing endlessly on this amp just to listen to the tone. The warmth can be addicting. I've heard a lot about this amp not being that loud, but it does a real good job for a 30 watt amp. I can be heard just fine in a room with my drummer, and my guitarist playing with a 4X12 cabinet and a 300watt Boogie head. Don't get me wrong, he could dust me if he wanted to, but for a small room, there's plenty of volume. I've often heard it said that this amp is fine for small venues, but not for larger halls. If you're in a band, and you're playing a larger venue, there really is no excuse for not using a PA, and just miking the amp. Don't get confused into thinking that each band member can just crank up their 300 watt amps and the band is gonna sound great. Unless you're very lucky, the only time a band sounds great playing in a large space, is when they're miked, and mixed through a PA by a competent sound guy or gal. Therefore, for practice, recording, or ANY professional live performance using a PA, this amp is great. It's also as quiet as can be. The transformers start humming if you get right on top of it with your bass, or if you turn on a TV right next to it (I learned this the hard way. After spending hours trying to figure why it was humming, I just turned the TV off and it stopped!). Otherwise it is really silent. When turned up past 3/4 (there are no numerical designations on the knobs) the amp does begin to break up, but it's a pleasing sort of breakup, that was put to great use on many early hit records of the 60's and 70's.

I haven't had a problem so far, and I wouldn't gig with it. This baby doesn't leave the studio! After using this amp for awhile, as reliable as it is, it becomes hard to believe that it was manufactured in 1966.

Ampeg may have a few usable parts for these amps, but your best bet is to contact Gregg Hopkins at Vintage Amp Repair, who can be reached at vintageamp@aol.com, or (314) 631-5030. Gregg is one of the authors of the new Ampeg book. He's very helpful, and stocks lots of parts for these units, as well as other old Ampegs. When I purchased my B-15, the amp was shipped with the head flipped down into the speaker cabinet. In transit, UPS gave it a good shot, and the rubber shock mounts that hold the head to it's mounting board gave out. The head slammed into the speaker magnet and took some damage (smashed fuse holder, speaker conector), and the shock mounts were destroyed. Amazingly, Gregg had the replacement shockmounts, and told me where I could get the other parts I needed around my own area. Let this be a warning! If you ship one of these amps, have the head and the cabinet shipped separately, lest your amp suffers the same fate that mine did! My customer support rating of 10 refers to Gregg Hopkins, at Vintage Amp Repair.

Just to clarify, I paid $450.00 for the amp, but that was without the original dolly. I found someone selling a dolly and original cover for $100.00, so with the dolly and cover I paid $550.00 for the amp. I've seen people saying they picked these up for less, but out on the West coast (SF Bay area) it's not uncommon to see these selling for over $600.00. Univibe in Berkeley currently has one for $625.00. I couldn't continue as a bass player without this amp! It is absolutely the coolest sounding, coolest looking, and just plain coolest piece of music gear I have ever seen! With the light up Ampeg plexi-plate, the blue check Tolex, the flip top, and the fantastic sound, this amp resembles a work of art more than just a guitar amp. Oh, I said I'd talk more about the speaker connector! There's a hard wired cable that comes out of the head that plugs into a 4 pin cannon plug on the side of the speaker cabinet. The top two pins are the speaker lines, and the bottom two pins complete a circuit when the plug is plugged, allowing the standby circuit to be shut off, and the amp to be played. If the plug is not plugged in, the amp will not come out of standby mode. This is to protect the amp from being played without a speaker attached, so that it doesn't go into fly away and damage itself. More coolness! For more info on this amp and other Ampegs, you can check out http://home.att.net/~gggjaguar/GGGJAG.HTM .