Why is a vintage Vox AC30 sooo (((LOUD))) ?

SirJackdeFuzz

New member
I had a conversation with a seasoned pro muso a few days ago.

We talked about vintage amps, and i brought up the 'vintage non-master volume amp volume thing'.

He told me (bloke now well into his 50's), i have to remember that an AC30 is sooo loud (or just as loud as a Plexi) because it is basically "three amps in one".

HUH ?

WUT ?




Can anyone see where he might have gone with this type of statement ?
Is there truth in this ? . . . i.e. did he just express him self incorrectly or is that just plain BS with zero understanding of amp circuits ?

I did not go any further into the subjet.
I just said somehting like, "oh, OK, i did not know that", walked away and looked for the strongest coffee i could find. i was in a coffee shop at the time.

So, please help me to understand what he was trying to "educate" me in !

Because i am 100% confused now . . .
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

That BS.

The AC30 is as loud as a Plexi because 30W are almost as load as the 50W the Plexi has. Also a 100W valve amp is not twice as load as a 50W because the loadness (the way we hear) follow a logarithmic curve and is not linear to the power of the amp --> a 10W amp is half as load as a 100W amp. Then of course also the speaker has an influence on the loudness
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

I don't even know what 3 amps in one means...

Folks tend to get hung up on an AC30 being so loud, and how odd that is and I have even been sucked into that BS before...

AC30's are loud but Fender Tremoluxes can also be as loud and they are also 30 watts...
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

Doesn't a large part of it have to do with the speakers and the character of the amp as well? AC30s have that chimey highend and with 30w almost being as loud as 50w and 100w, it seems to me what would really make it seem like it's louder is the very efficient Vox Alnico Blue speakers and the boosted upper frequencies.
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

Doesn't a large part of it have to do with the speakers and the character of the amp as well? AC30s have that chimey highend and with 30w almost being as loud as 50w and 100w, it seems to me what would really make it seem like it's louder is the very efficient Vox Alnico Blue speakers and the boosted upper frequencies.
Yeh agreed when a VOX AC30 starts to breakup it still kinda sounds "clean" but has alot of high end harmonics that really cut through and probably is a higher THD then what you you'd consider "clean"on other amps also high end doesn't need as much power to reach the same percieved loudness (hence why bass amps need be high wattage). The speakers are really loud too and add more of that high end!
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

I think it's highly likely that you're placing too much emphasis on what the guy said ... it was probably more of a throwaway comment, a casual opinion ... he may have meant that they sound as loud as three other amps of that physical size, he may have meant that the AC30 is a Fender, Marshall and Vox all in one (as they have been used successfully in situations where one might think a Fender or Marshall would have been the amp of choice) .... don't try to read anything into it, other than that he may have been expressing either his like or dislike of the amp in question.

Besides, strange and even stupid comments are not exclusively the realm of younger people. Just trust your own ears, it's that simple.
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

The issue with the speakers is this...

New Celestion Blues are rated at 100db's however based on all my research original 60's G12 alnico's were not that loud...closer to 98db or so when they were brand new.

I can also say this...I have a 1968 G12 alnico that I use in my 62 Deluxe and it is louder than a standard reissue greenback (which is 97db's) but not nearly as much as you might think and it is less loud (a lot less loud!) when compared to an H30 or a V30, both of which are 100db

Now, the freq range of the AC30 might make it seem louder since it's almost all midrange and a lot of it is upper midrange but at least in vintage examples the speakers are not nearly as big an issue as you might think...
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

96db Greenbacks vs 98db Alnico Blues.

You also need to factor in the bottom end. Low end eats up a lot of headroom. Most lower powered amps have the bottom end cut off at a higher frequency so that they can produce louder midrange.

Edit: TGWIF beat me to it.
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

I think it's highly likely that you're placing too much emphasis on what the guy said ... it was probably more of a throwaway comment, a casual opinion ... he may have meant that they sound as loud as three other amps of that physical size, he may have meant that the AC30 is a Fender, Marshall and Vox all in one (as they have been used successfully in situations where one might think a Fender or Marshall would have been the amp of choice) .... don't try to read anything into it, other than that he may have been expressing either his like or dislike of the amp in question.

Besides, strange and even stupid comments are not exclusively the realm of younger people. Just trust your own ears, it's that simple.


. . . i think you might be onto something Crusty.
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

Besides doesn't the AC30 really rate total 65 watts?
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

sometimes when i hear people talking about how loud AC30's and plexis and twins are, they're referring to the lack of preamp, causing you to light up the power tubes for any good overdrive.
 
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Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

Besides doesn't the AC30 really rate total 65 watts?


No... you wont get 65 watts RMS out of 4 EL84's. Now if your push them into clipping you will go above a RMS value but then again all amps will do this. Once for giggles we measured the output of my Marshall JMP and at 5% THD it was putting out 90 watts. So if you push a AC30 that hard you might get that much power out of but you would never rate it as such.
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

He might have meant that there is a top boost and a normal channel and in some models it is possible to combine the two. Only thing I can think of.
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

Guitarded is on the right track. An AC30 is essentially two AC15's smashed together. I have an AC15TB and from what i have read, it is essentially the top boost channel of an AC30. I dont know why that would make it louder tho.
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

I don't even know what 3 amps in one means...

Folks tend to get hung up on an AC30 being so loud, and how odd that is and I have even been sucked into that BS before...

AC30's are loud but Fender Tremoluxes can also be as loud and they are also 30 watts...

Even 5watts into a 4x12 cab can be bloody loud. It's in the speakers and the number thereof!

...also, there IS that thing where twice as loud as 30 watts has to be 300 watts or so, not 60 watts, not even close. Add to that the wattage rating nonsense of SS amps, and the habit of some less-than-honourable manufacturers to put POWER CONSUMPTION WATTAGE (which is something like 275 or 350 watts, can't recall, on a 100watt marshall), thereby tripling it once, or even getting ENTIRELY cocky and putting down something called "peak wattage" or something, which takes the previous number and DOUBLES it again... all in all, our perceptions off wattage are thrown off by manufacturers using two billion different ways of measuring them.
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

It's an e.q./distortion thing. They seem loud as hell because they are so trebly and crunchy.
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

Btw, just saw a reissue at GC today.... SOOOO lame, SOOO wrong, SOOOO offf.

The new ones are hella quiet, if you can believe that!! Fixable via tubescreamer, but really, what the heck was the point of building a tube circuit that can't even get 10% of its tubes' possible crunch using the dials, not even when putting freakin BLACKOUTS directly to the input jack?!?! And what extremely bright, special kinda person got the genius idea to call that misunderstanding of an amp an AC30 reissue?!??!

I vaguely remember the REAL thing: plugging actives into it, even with volume set to like halfway between 0 and 1, was a bloody revelation. This, though? Bloody joke is what it is.
 
Re: Why is a vintage Vox AC30 sooo (((LOUD))) ?

Btw, just saw a reissue at GC today.... SOOOO lame, SOOO wrong, SOOOO offf.

The new ones are hella quiet, if you can believe that!! Fixable via tubescreamer, but really, what the heck was the point of building a tube circuit that can't even get 10% of its tubes' possible crunch using the dials, not even when putting freakin BLACKOUTS directly to the input jack?!?! And what extremely bright, special kinda person got the genius idea to call that misunderstanding of an amp an AC30 reissue?!??!

I vaguely remember the REAL thing: plugging actives into it, even with volume set to like halfway between 0 and 1, was a bloody revelation. This, though? Bloody joke is what it is.
This is why people try other companies like Bruno Amps or Valvetech for AC30s, I have played the reissues and they sound pretty fine to me nice clean kinda sound but couldnt crank it in store so don't know how they stack up against 60s and early 70s ones.
 
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