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Mesa 400+ vs Mesa 400 ?

The regular 400 has 6 6550 power tubes in it and probably sounds better with those tubes and with 6 6550 tubes it should check in at around 300 watts.

The 400+ has 12 6L6 tubes in it and should check in at around 300 watts. I think the 400+ has one extra slider on the EQ band also.

I would go with the regular 400 and that is a good price. It would be less to retube and those 6550 tubes probably do not sound as mushy and muddy as those 6L6 tubes would.
 
The one im looking at was recently retubed with six str454 6L6 tubes. Am I also correct to assume that it can push a WHOLE lot of sound being that its all tubed? My friends old old ampeg b25 head is 35 all tube watts I think and it can get LOUD. Would I be able to power an ampeg 4x10 to 500 watts and a 1x15 to their max?
 
Originally posted by ampegsvtca
I used to own a Bass 400 with 6-6550's and I don't think that it puts out 300W, probably more like 220W. If you compare it to an SVT the transformers are not nearly as big (or heavy).
thats why they came out with the 400+. So if you need the volume go with the 400+.

Technically, the 400 was good for about 300 Watts while the 400+ is good for less. I'm not getting technical (6550 vs. 6L6), but you should be able to track this down in a search. :p
 
I had a 400+ with svet power tubes in it - my '73 SVT absolutely slayed it in terms of volume, but I think a lot of that has to do with the fender tone stack in the mesa. With my SVT's I boost mids so they *sound* louder. I never could get enough mid out of the 400+, so I sold it.
 
Originally posted by I.'.I.'.Nakoa
No, im sorry. a 400+ is 500 watts. read the website.


It says 500W peak.....

A 6l6 can produce a maximum of about 25W per unit on a continuous basis. Most do less. The ones Mesa uses are spec'd at 25W. There are 12 of them. Do the math.
Mesa isn't really lying, but they aren't telling the whole truth. Pretty much any 300W amp can do peaks of 500W.

I've had a couple of 400+s on the scope. They start to clip at about 300W.
 
I tried to tell em too. Check the first reply I explained the whole thing i terms of tube=watts thing. Oh well some just will not listen. I owned a 400+ and was loud as heck. Trust me you will not really need anything louder. But the question is will you need something cleaner that gets that loud!;)
 
Originally posted by Flat Bass
I tried to tell em too. Check the first reply I explained the whole thing i terms of tube=watts thing. Oh well some just will not listen. I owned a 400+ and was loud as heck. Trust me you will not really need anything louder. But the question is will you need something cleaner that gets that loud!;)


I should have added the comment that despite the power ratings thing, the 400+ is a killer sounding amp and it is loud as hell. The numbers don't matter.
 
actually, i think the bass 400+ is cheaper to retube and more reliable. I asked mesa boogie about that and here is what tim from mesa told me: "Olivier

We only made the Bass 400 hundered for a short time. (only 1200 out there I
believe) 6550s are great tubes and known for their bold and punchy response.
The 400+ is in no way muddy - unless you have worn tubes in it. 6L6s put out
about 50 Watts per pair where 6550s boast a bit more per pair. However, when
you have an amp with 12 6L6s in it vs. an amp with only 6 6550's, there would
not be that much difference in headroom. If you are looking for a used Bass
400, I would say go for it! They are great amps. 6550's however are not so
reliable any longer and are very expensive. We stopped carrying them in fact
because of the high failure rate and the high cost of replacing them. A Bass
400+ with 6L6 tubes will be plenty bold and punch with a nice rounded tone.
With 5881's though (which they did ship with for awhile) you will have less
output wattage, less headroom - which may provide the fuel for rumors that the
400+ is muddy. They simply break up sooner and when those tubes break up, the
top rolls off a little bit and you are left with a rounded and vintage
sounding mid range. One would have to play very loud if that was the case
with newer tubes but worn tubes can easily provide that undesireable tone. It
is all pretty subjective. We are shipping 400+ amps with 6L6 STR 430 tubes.
A full output 6L6 from the Sovtek factory in Russia.
 
I'm sorry, but that's a total load of crap concerning the tubes.

Originally posted by Shri
We only made the Bass 400 hundered for a short time. (only 1200 out there I
believe) 6550s are great tubes and known for their bold and punchy response.
The 400+ is in no way muddy - unless you have worn tubes in it.

I see that Mesa wastes no opportunity to hawk its tired and false sales pitch of "worn tubes." Tubes are voltage amplifiers, PERIOD. They either work or they don't. If there's a change in their "sound," it is a result of the circuit not meeting their bias current needs. Tubes don't 'dull' as they age; they only change their current draw, which isn't a problem in an amp with an adjustable bias capability. Guess what Mesa doesn't have?

6L6s put out about 50 Watts per pair where 6550s boast a bit more per pair.

It's funny he says "a bit" more (GOOD 6550's, not the Chinese junk Mesa used to push, put out roughly twice what a 6L6GC does) and then glosses by later with this:

However, when you have an amp with 12 6L6s in it vs. an amp with only 6 6550's, there would not be that much difference in headroom.
...

6550's however are not so
reliable any longer and are very expensive. We stopped carrying them in fact
because of the high failure rate and the high cost of replacing them.

No, Mesa's Chinese 6550's were VERY cheap and unreliable, but they charged premium prices for them and touted that they were equivalent to the American 6550A's they used to carry.

A Bass 400+ with 6L6 tubes will be plenty bold and punch with a nice rounded tone.
With 5881's though (which they did ship with for awhile) you will have less
output wattage, less headroom - which may provide the fuel for rumors that the
400+ is muddy.

The "5881's" Mesa shipped (at least the Sovtek 5881's) are great tubes, but NOT at the voltages that the 400+ uses. They would perform better with MORE voltage. The "mud" in their tone comes from the tone stack in the preamp, which is based on the classic Fender scooped midrange tone stack. In contrast, the Ampeg SVT has an agressive midrange boost which helps the sound cut better and contributes to a greater overall volume level, since we hear midrange frequencies much better. I don't think the 400+ is a muddy sounding amp, but it's not very agressively voiced either, more R'N'B than rock and roll.

They simply break up sooner and when those tubes break up, the top rolls off a little bit and you are left with a rounded and vintage
sounding mid range.

This much at least is true. Highs are one of the first things to go in an overdriven amp with a relatively low voltage power supply. Plate current drops, and highs which carry more peak voltage content, get attenuated. It's exactly the same effect as a compressor, hence, it's called output compression.

One would have to play very loud if that was the case with newer tubes but worn tubes can easily provide that undesireable tone. It
is all pretty subjective.

...again with the "worn tubes" line, total BS.

We are shipping 400+ amps with 6L6 STR 430 tubes.

Mesa's "STR" designation is stolen from Fender in the 70's, when CBS redesigned higher voltage versions of old Fenders and ultralinear amps and needed a 6L6 which could take higher voltage and operate inverted without shorting. Sylvania (later Philips which bought them out) came out with the 6L6GC STR which stood for "special test requirement."

Mesa has used the "STR" as an attempt to confuse its customers. They USED to carry STR 6L6GC's (D180's came stock with them.) when they were more widely available and rather than admit that the later Chinese 6L6's they sell were of lesser quality, the "STR number system" was used. It's meaningless and serves only to discriminate between country of origin now, but they way Mesa touts it, most people mistakenly assume it to mean something it doesn't and Mesa encourages that belief.

As far as which version of the Bass 400 is better, just play them! If you come across either amp and you like it, then use it. All this "best" crap is like a bunch of grade school kids bragging about their toys.
 
Uhm... interesting your comments. And i know also that if i use different tubes than mesa's, the guarantee will end. I find that very bad !!! Especially for expensive mesa tubes that are just cheap chinese ones. But he told me that there are russian ones also (sovtek).

I still hesitate between the 400+ and the SVT-CL of Ampeg which is great also.:bassist: