Ampeg B15-S Suggestions

[lmfreeman9]

Just scored one of these that needs work. Probably new tubes, and a speaker which is currently a JBL 130.

I mostly use P-Basses and flats and play blues and classic rock and am looking for that syrupy, buttery, greasy, thick old school sound of a B-15-N I once tried.

Thanks to JimmyM whose advice was instrumental in helping me decide to purchase it.

I am looking for more first hand recommendations on speakers, tubes, etc to make this monster sound like it once did or better.

[bluestarbass]

Im not sure what kinds of tubes that takes. I'd guess 6l6 of some variation. RCA's if you want expensive old, JJ/Tesla's if you want reasonable new production. I really like anything JAN, which i realize are different brands. I think JAN tubes are still semi reasonable and thats all I've got in my guitar amps. What about getting the speak reconed? I dont have a ton of experience with swapping speakers but usually everyones answer when it comes to replacing old ampeg speakers is to recone.

[RickenBoogie]

It most likely needs more than just new tubes. I'd take it to a reputable amp tech and have it looked over closely, for capacitors, biasing, etc.

[JimmyM]

Originally Posted by bluestarbass

Im not sure what kinds of tubes that takes. I'd guess 6l6 of some variation. RCA's if you want expensive old, JJ/Tesla's if you want reasonable new production. I really like anything JAN, which i realize are different brands. I think JAN tubes are still semi reasonable and thats all I've got in my guitar amps. What about getting the speak reconed? I dont have a ton of experience with swapping speakers but usually everyones answer when it comes to replacing old ampeg speakers is to recone.

you know, you just reminded me...when they recone d130's these days, they use the recone kit for the jbl d140. that would make it a lot more useful for bass, and it should handle a b-15s no problem. it's not cheap, but it's about the same price as a vintage speaker. d130 just doesn't have enough ass for bass. sounds great at low volumes but even the 30w b-15's could take them out.

www.orangecountyspeaker.com is the best speaker reconing joint according to everyone i've talked to.

[coreyfyfe]

I think the B15S uses 7027s if I'm not mistaken, but those can be swapped for 6L6s fairly easily. As for the speaker, I'm with Jimmy on reconing instead of replacing. I have a JBL K140 in my 65 B15N and it's a really fantastic sounding speaker, and if they're using the 140 kits to recone the 130, it could work out well. You can find original speakers floating around on ebay, as well at the Altec 421s which were the "upgrade" available from the factory.

Fliptops.net sells a full tube set package for those which is all JJ's:
http://www.fliptops.net/catalog/prod...tymvprxmclimnr

Your pre tubes are probably fine, might need power tubes depending on how old they are. I'm a fan of taking any "new" vintage tube amp to a reputable tech for a good once over soon after purchase. Can't hurt, especially for these vintage pieces which may have a less-than-perfect history.

[coreyfyfe]

Oh yeah, and we need pics!!!!!!

[MR PC]

The B15-S can be easily modded for 6550's, according to Aspen Pittman. What a great piece of gear you have there! I've played through a couple, but they seem to be pretty scarce out here on the west coast. I wish Ampeg had made more of these. From what I know, it's different than than rest of the fliptop line, with an power amp that's more like a McCintosh monoblock, and a much more HiFi preamp too.

EDIT: I believe the amp was issued with 7027's.

[coreyfyfe]

Originally Posted by MR PC

The B15-S can be easily modded for 6550's, according to Aspen Pittman.

They can, similar to V4s, but AFAIK people did the conversion when 7027s were out of production and not necessarily as a means of getting more headroom/wattage out of the amp.

[lmfreeman9]

tubes are: 2-12AX7, 1-12DW7, 1-12AU7, 2-7027
according to Unoffical Ampeg pages, I was planning on buying them from Fliptops.
I already have it with a tech and have a line an Altec 421A for $100 which I would think would trump the Stock JBL, which I would sell.
One last thing, I'm looking to get this to sound more like a B15-N. Should I go with the Altec or the cheap Deltas that Fliptops recommend?
Here's the photo of the head, thanks for all the imput thus far.

[KramerBassFan]

Keep us updated!

I'd love a gut shot too.

[JimmyM]

Originally Posted by lmfreeman9

tubes are: 2-12AX7, 1-12DW7, 1-12AU7, 2-7027
according to Unoffical Ampeg pages, I was planning on buying them from Fliptops.
I already have it with a tech and have a line an Altec 421A for $100 which I would think would trump the Stock JBL, which I would sell.
One last thing, I'm looking to get this to sound more like a B15-N. Should I go with the Altec or the cheap Deltas that Fliptops recommend?
Here's the photo of the head, thanks for all the imput thus far.

altec.

[MR PC]

Altec 421 is the best for fliptops, IMO. The smaller voice coil breaks up just right. JBL is cleaner. 6550's sound and better for bass than 6l6. Stick with some nice 7027's if you can find them. I've owned and gigged every type of fliptop except the b15-S. Closest to the sound of this amp is the check tolex B-18...........bass + treble maxxed, and volume at one o'clock, you've got chocolate tones spreading over everything in the room. Above that point it really roars. If you have a roots band that isn't slaying with stage volume, there is nothing better than this sound!

[RobertPaulson]

Let me know what you decide on the speaker, I'm thinking of replacing the one in my B15s, but can't make up my mind

[johnk_10]

i'd have the JBL reconed as a 140. they actually use an E140 kit now, so it would be most like a K140 which, IME is the best speaker that you could put in one. i never liked Altecs in them at all (too honky) and preferred the stock CTS speaker over an Altec.

for the best output tubes, i'd go with a pair of NOS 7581A's.

2 cents.........

[pedro]

No advice just a congrats. (pedro a happy B15S owner)

[JimmyM]

Originally Posted by johnk_10

i'd have the JBL reconed as a 140. they actually use an E140 kit now, so it would be most like a K140 which, IME is the best speaker that you could put in one. i never liked Altecs in them at all (too honky) and preferred the stock CTS speaker over an Altec.

the reason i chose the altec is because those bigger thiele cabs could stand a little upper mid boost. just my opinion, but one thing i did notice with the delta 15a in a thiele cab is the upper mids aren't quite as strong. you can dial them in, but i would think the altec would make you not work so hard for it.

[lmfreeman9]

Originally Posted by johnk_10

i'd have the JBL reconed as a 140. they actually use an E140 kit now, so it would be most like a K140 which, IME is the best speaker that you could put in one. i never liked Altecs in them at all (too honky) and preferred the stock CTS speaker over an Altec.

for the best output tubes, i'd go with a pair of NOS 7581A's.

2 cents.........

On the speakers, I'm after pure bottom. I have flats on all but one bass and I generally run the tone rolled off to 10-20%.

I now have a line on 2 altecs at good prices. But I'd like to know what speaker will give me the best bottom? Honky is not for me.

Also on the tubes, please clarify the suggestions by recommending a whole set. No offense, I'm new to this world and just confused.

I will attempt to put up a poor photo of the cabinet later.

[coreyfyfe]

Originally Posted by lmfreeman9

Also on the tubes, please clarify the suggestions by recommending a whole set. No offense, I'm new to this world and just confused.

7581As would sub for the 7027s (power tubes). Your pre-amp tubes (the 12AX7s and 12DW7) that are in there now are probably ok and unless you're getting noise from them you can probably stick with what you have.

[salcott]

7027s are readily available both new and NOS. The easiest tube swap is no tube swap. Here's a good source for all things Ampeg: http://www.fliptops.net/

[lmfreeman9]

This thing has been in storage for 10 years. Maybe I should have mentioned that. Also, it sounds real farty. Breaks up way too soon, may be the speaker.