The Ampeg V-4B

[anderbass]

Personally, I think they sound sorta similar. I have never a/b them as I only have one cab, but both sound like ampeg. The V4 sounds better at lower volumes I think. The V4 would be my choice for smaller gigs. The SVT, of course, for when I need more power.. like outside gigs or when I think I might need a little extra! I would say the power needed is the defining factor, not tone.

+1... I own both and pretty much agree with ya denton. Although I do notice a few subtle tone/feel differences I cant really find the right words to describe.
I love playing my V4 and consider its tone (and volume level) to be kind of a halfway point between the B-15n and an SVT.

 

[bobyoung53]

Personally, I think they sound sorta similar. I have never a/b them as I only have one cab, but both sound like ampeg. The V4 sounds better at lower volumes I think. The V4 would be my choice for smaller gigs. The SVT, of course, for when I need more power.. like outside gigs or when I think I might need a little extra! I would say the power needed is the defining factor, not tone.

I had a real early one, was a nice little amp for quiet gigs, always brought out the SVT when I thought I may need it. 6L6's are really not very good for these as the 7027A's are a heavier duty tube and should last longer. 6550's do need some change in the amp and if it's set up for 6550's I wouldn't put 7027A's in it without changing it back. The tone centers on the V4-B's are different than SVT's, I thought V4-B's were more mellow sounding, I like the SVT heads sound much better. The original cabs had double 15"s in them and were a kind of folded horn type cab, were the size of an SVT cab but about twice as deep, lots of bottom out of them and very efficient, they were similar to Sunn 2000S cabs but much deeper (physical depth) and sounded deeper too.

 

[doktorfeelgood]

I have an original 1966 Ampeg B-18-N and it still has the original working 7027 A's in it. Those tubes were originally labeled as JAN (joint Army/Navy) 7027A's and were originally designed for military use because they were pretty much bullet-proof and would last for a ling time as well. If your amp has the original 7027's, they will probably sound better than the newer ones that are available today. Back about 10 years ago, there wasn't anybody making new 7027's and I considered changing out the tube sockets for 6L6's but I didn't and I'm glad. I don't use the amp now for more than a table in my studio (God forbid...) and probaly won't unless I get to do some recording sometime soon. The amp was given to me by my Uncle and I keep it not only because it's a cool amp and a collector's item, but because it came from family. )-(

 

[pedro]

Personally, I think they sound sorta similar. I have never a/b them as I only have one cab, but both sound like ampeg.

Well I'm sure that all the Ampeg tube amps have some characteristics in common. I ask because back in the early 70's I occassionally would use a SVT and never really warmed up to it. The only time since that I've played thru SVT's was newer stuff in music stores and had similar impressions. But the VB has a softness to the sound that sounds (to me) more like my B15S. Anyway, it would be way cool if some day you did A/B the two.

 

[pedro]

The tone centers on the V4-B's are different than SVT's, I thought V4-B's were more mellow sounding,

Yea that's perhaps what I was noticing. You prefer the SVT bite but to me, in the kind of music I play (soul/r&b) the VB seems a better fit. Perhaps if I was playing classic rock I'd lean more towards the SVT. In fact, as much as I love my VB and B15, I'm seriously thinking I'd better give an SVT another try someday.

 

[nysbob]

I have both too...frankly the V4B is plenty of juice for 80% of the gigs I play.

I still love my SVT, but some gigs don't allow you to even get into it's sweet range, so the V4B is a nice alternative. I've got one with very old RCA 7027s in it.

 

[bobyoung53]

I have an original 1966 Ampeg B-18-N and it still has the original working 7027 A's in it. Those tubes were originally labeled as JAN (joint Army/Navy) 7027A's and were originally designed for military use because they were pretty much bullet-proof and would last for a ling time as well. If your amp has the original 7027's, they will probably sound better than the newer ones that are available today. Back about 10 years ago, there wasn't anybody making new 7027's and I considered changing out the tube sockets for 6L6's but I didn't and I'm glad. I don't use the amp now for more than a table in my studio (God forbid...) and probaly won't unless I get to do some recording sometime soon. The amp was given to me by my Uncle and I keep it not only because it's a cool amp and a collector's item, but because it came from family. )-(

6L6's as well as 6550's are direct replacements, the pin outs are the same, just that I believe the 6550's need the bias changed and the 6L6's aren't really up to the task,I think the plate voltage is too high although many people have used them. I own a late 70's B-15S that had original Magnavox 7027A's in it, they still worked but I bought some NOS's for it (RCA? I forgot). Now that is a bassy amp, nice for small rooms though, weighs a ton. I use Jan tubes whenever I can get them for my ham radios.

 

[Hookus]

6L6's as well as 6550's are direct replacements, the pin outs are the same, just that I believe the 6550's need the bias changed and the 6L6's aren't really up to the task,I think the plate voltage is too high although many people have used them.

Beat me to it. In the V-4, 6L6 and 7027 are interchangeable. You actually can use several other types of tubes as well, but, as bobyoung53 and I already stated, the retainers and bias change. Sockets and pinouts do not. Ampeg actually at the time was a leader and innovator in tube amp technology (hello Super Valve Technology....), and one of the innovative things they did was to design amps that will work with any tube you could fit into the socket.

 

[bobyoung53]

Yea that's perhaps what I was noticing. You prefer the SVT bite but to me, in the kind of music I play (soul/r&b) the VB seems a better fit. Perhaps if I was playing classic rock I'd lean more towards the SVT. In fact, as much as I love my VB and B15, I'm seriously thinking I'd better give an SVT another try someday.

Yes, I love the bite considering my rock background, nothing sounds like an SVT when it's played near the edge. But I play a lot of blues now in my old age and use two early 90's B-15T cabs with the SS heads taken out and they sound really nice with an SVT head, sound like a big giant clear B-15, very warm. They have 4 ohm Eminence 150 WRMS 15"s in them, just right for an SVT head, I've even pushed them and they stand up to the mighty SVT. If you want an SVT, get a 70's, any year, in fact you may be better off getting a late 70's, they have less wear and sound just as good as the early ones, I've owned both. They all kill the newer ones both in volume and sound.

 

[bobyoung53]

Beat me to it. In the V-4, 6L6 and 7027 are interchangeable. You actually can use several other types of tubes as well, but, as bobyoung53 and I already stated, the retainers and bias change. Sockets and pinouts do not. Ampeg actually at the time was a leader and innovator in tube amp technology (hello Super Valve Technology....), and one of the innovative things they did was to design amps that will work with any tube you could fit into the socket.

I'll tell you a good one, my wife is from Lima, Peru, I lived there for a year about 5 years ago. I bought a late 70's Magnavox head for 300 bucks, it worked but was so microphonic it was unplayable. Took it apart and found it had 6L6's in it with no mods! One side had the bias all the way up, the other side had the bias completely off, it played that way and the tubes didn't glow cherry red, got pretty hot though (three on one side, the other three were cool), amazing. I thought it had been modded until I really got into it. They were all old GE tubes taken from Fender amps, you could see the bear trap marks on the sides. I redid it and it still sounds good to this day. Lima is the micky mouse capital of the world.
I brought this thing home on a plane, haha!

 

[pedro]

sound like a big giant clear B-15, very warm

Yea but you see I think a 'clear' B-15 looses some of its charm. Although I've not gigged w/ my B15S I honestly think that with the kind of music we do, and at the volumes we play at, I could gig with it. And yea, I like a little dirt in my bass. But isn't some breakup also the charm of an SVT?

 

[bobyoung53]

Yea but you see I think a 'clear' B-15 looses some of its charm. Although I've not gigged w/ my B15S I honestly think that with the kind of music we do, and at the volumes we play at, I could gig with it. And yea, I like a little dirt in my bass. But isn't some breakup also the charm of an SVT?

Yeah but they also sound good when they're not cranked, I use it when I host blues jams and most bass players love the sound, even non-bass players love the sound of it. I think the 70's heads always have a little bite to their sound even when soft anyway. I think part of that is the very high gain of their preamps.

 

[pedro]

Yeah but they also sound good when they're not cranked,

No argument from me. But to my ears, my VB/B15's sound their best when there is some breakup. Now I'm not talking total distortion city but think Jamerson and Motown and you got it.

 

[bobyoung53]

SVT's break up very gradually, it doesn't get noticable until they're really loud. A good B-15 sounds great when pushed.

 

[bobyoung53]

No argument from me. But to my ears, my VB/B15's sound their best when there is some breakup. Now I'm not talking total distortion city but think Jamerson and Motown and you got it.

I hate to say that but according what I've read Jamerson almost always played direct through a special board Motown had built. He's tops for electric bass for me, no slouch on upright either.

 

[JimmyM]

Even though he used a DI, that sound he had was identical to a B-15. I'm sure the 15" monitor bled and got on the tracks, and I'll bet it sounds like a B-15.

 

[pedro]

I hate to say that but according what I've read Jamerson almost always played direct through a special board Motown had built.

True but I'm just saying that I much prefer when B15/VB has some dirt in it like Jamerson did.

 

[doktorfeelgood]

6L6's as well as 6550's are direct replacements, the pin outs are the same, just that I believe the 6550's need the bias changed and the 6L6's aren't really up to the task,I think the plate voltage is too high although many people have used them. I own a late 70's B-15S that had original Magnavox 7027A's in it, they still worked but I bought some NOS's for it (RCA? I forgot). Now that is a bassy amp, nice for small rooms though, weighs a ton. I use Jan tubes whenever I can get them for my ham radios.

This is good to know. I was under this assupmtion because one of the (supposedly) better techs in my area told me I'd have to change out the tube sockets. It's all moot now as 7027's are being made again. But, as usual, the knowledge gained by being here is invaluable. Thanx... )-(

 

[pedro]

Question for the techs - I noticed at practice this afternoon that my standby light is out. The amp works fine but the light is out. Is this something that has to be fixed right away or is it more of a convenience for the user thing.

 

[JimmyM]

Oh no!!! Not the standby light!!! Pedro, unplug the amp with a fire extinguisher in your hand just in case, then run out of the house ASAP and call the fire department.

Just joking...I wouldn't leave it too long but it should be fine. Sounds like the light either just burned out or got corroded or something. If you have any contact cleaner, spray its connections and clean any corrosion off of it. I'm not a tech at all but I've gotten similar lights to work again doing that.