I can say this now: The Vox AC4C1-12 is a terrible amp.

Sax-son

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I often find crap sounding amps are really attributable to crap speakers. A speaker swap or cab hookup usually improves matters. YMMV.
I agree! I have a Vox AC-15 C1 that I love now, but not when I first got it. The amp had no head room whatsoever. I replaced the mismatched Celestion Greenback for a Weber Bluedog 12" 50 watt. It sounds great now. I also replaced the Chinese tubes with JJ's and that also was a plus. I installed the Greenback into my Hughes and Kettner solid state and it shines in that.

If you are looking for the "ultimate" small practice amp, then perhaps the AC-4 12 is not the ticket. However, experimenting with a separate cab and speaker may find some interesting results. I think Vox is trying to keep these amps at a reasonable price point to which you may have to invest additional money in order to get these to where you want them. It something to think about.
 

pgoodwi1

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Port the back panel, swap the output transformer for a Classic Tone 40-18031 (same as I use in tweed Princeton). Alnico speaker. And get some Mullard RIs. Done.
14703C5A-A3B1-4D32-B360-BEB7F00623FE.jpeg
 

Collin D Plonker

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Why would they build a Vox AC that's always in "Top Boost"? My understanding is that Vox developed the "Top Boost" for those take the lead moments when you really needed to cut through the mix. I can't think of any situation where a guitarist would want that in play at all times. Even if a player did, for whatever reason, they'd still need the dampening effect of the original Alnico Blue speaker to control the high end. The circuit needs all the other parts to sound like the circuit was designed to sound like.
I have an AC10 that sounds great clean or dirty, and it's all top boost.
 

feldkeen

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I just sold mine for a mere $120. I just wanted it gone. Kept trying to figure out how to get a good sound but it always sucked. AC4-C1 Blue.
 

TonyClark

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I agree! I have a Vox AC-15 C1 that I love now, but not when I first got it. The amp had no head room whatsoever. I replaced the mismatched Celestion Greenback for a Weber Bluedog 12" 50 watt. It sounds great now. I also replaced the Chinese tubes with JJ's and that also was a plus. I installed the Greenback into my Hughes and Kettner solid state and it shines in that.

If you are looking for the "ultimate" small practice amp, then perhaps the AC-4 12 is not the ticket. However, experimenting with a separate cab and speaker may find some interesting results. I think Vox is trying to keep these amps at a reasonable price point to which you may have to invest additional money in order to get these to where you want them. It something to think about.
I hear ya Sax. I love my AC15 C1 (Creamback Speaker) since I tweaked it with new tubes and a less "boingy" reverb tank. It does give me a nice little workout when I move it around but that's ok, the sound is epic now!

I also love my little AC4 (10") more so since it's gotten over 4 years old. I haven't changed anything on that one except I did add reverb. I've even recorded with it because it has a great overdriven tone at low volume.

AC15-AC4.jpg


AC4-Back-Reverb.jpg
 

Snfoilhat

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Top boost was originated in 1961 as a mod to the '59-61 AC30s, right? I wonder if the idea of channel switching and any kind of lead boost was in players' vocabularies at that time, or if Top Boost the name just doesn't really fit what it does. I don't see (schematically) or hear TB being especially bright or boosted compared to other EQ on other amps. The Matchless Lightning is a TB-only derivative of the old ACs, and it has a reputation for being really bright. But I've built a couple amps faithful to the TB plans and I think the interactive bass control makes it usually less bright than, say, a Fender at most settings.

Over the years, Vox may have in fact changed the TB channel to fit better with the assumptions players take from the name! Since to an amp company, the specific circuits are often not especially valuable but the trademarks and other pieces of language associated with the brand can be very valuable

Edit to add: that interactive bass I mentioned is an example of one of the changes Vox or Korg made at some point -- there are amps that wear the TB name that have tone stacks that are more like a Bassman. You'd have to ask around the company, but I would throw out a guess that it's to make the original TB tone controls less of a puzzle to set and never mind historical accuracy or consistency
 
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alesplin

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I went back and forth at the store for like an hour between the AC4C1-12 and AC4C1-BL back when I bought my amp (the AC4C1-BL).

In the store I could tell that the 12” speaker had noticeably more low end than the 10” speaker in the blue. I bought the blue 100% because it was cheaper, and I’ve wished many times over the last 6-7 years that I had gotten the 12.

However, I just swapped in a Celestion Greenback in the blue and the low end it does have is considerably tighter now. At some point I may make an extension cab with a bigger box to put the original speaker in. But the Greenback will definitely make me happier until I save up for a bigger amp.
 

Smitty088

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For several months I refused to say it, because I spent my hard-earned $$ on one (beige). It look great. Sounded terrible. And the ironic thing was that I thought I was moving up from my AC4TVH, but that amp actually sounded better. So for the longest time I forced myself to embrace the trebly tone with absolutely no bottom end, and (probably) decent mids that were simply stomped all over by the treble.

The problem: not the 12" speaker, swapping other speakers into it did not help matters. It's the shallow cabinet design. You simply cannot make an a cab that size produce good bass response. Tubes? Nope, swapped those out at as well, only resulting in differing amounts of preamp gain.

So now that I no longer have this amp, and have no need to lie to myself about how "good" it was, I can now say that it's a terrible amp. Second place: The Vox Night Train NT-15. I tried to love that amp also. Sounded terrible.
It sounds like VOX isn’t really the tone you’re looking for. All early Brit amps were made bc import duty made Fender amps too expensive for most Brit players. Yes Jim Marshall did ‘try’ to clone a Fender bass man but he couldn’t access the exact same caps, resistors, transformers, etc that Leo used so he used what was available. Hence the difference in tone. I will admit most VOX amps like vintage Marshall’s sound very trebly at lower volume settings. In the 50’s 60’s pickups in Europe were also darker and lower output so it evened out. The best sound of any Brit voiced amp is cranked. Don’t expect it to sound like a Fender, it has its own sweet voice but must be LOUD 😊👍🏻
 

mfratus2001

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Maybe the problem is those short-plated (usually JJ) ECC83's that nearly everyone is using. They are cheap to resellers. I think they are shrill and have no bottom end. Put in some old Marshall preamp tubes, or long-plate ECC803's. Really, most long-plate tubes sound better than short-plate tubes unless you want the shrillness.
 

Angler Dave

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I have a Vox AC4TV which I came by as part of a deal for a guitar I wanted. Lots of folk on the interweby demoing how "great" it sounds but they didn't and mine certainly didn't, horrible boxy sound with an unpleasant tone. Echoing what others have said here I suspected it was down to the internal speaker. Being a bit short of 16ohm cabs I hooked it up to the speaker in my Blackstar Studio10 6LC combo, a 12" Celestion Seventy 80 which is not even a particularly well liked speaker, and it immediately sounded very good, addictively so spurring me to lose track of time playing it. I went instantly from hating it to quite liking it; why only quite ? Well, I still find its being a complete desert of useful features, bells & whistles hard to get along with. OK: the output attenuator is fairly useful.
 
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Lester Paulbanez

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For several months I refused to say it, because I spent my hard-earned $$ on one (beige). It look great. Sounded terrible. And the ironic thing was that I thought I was moving up from my AC4TVH, but that amp actually sounded better. So for the longest time I forced myself to embrace the trebly tone with absolutely no bottom end, and (probably) decent mids that were simply stomped all over by the treble.

The problem: not the 12" speaker, swapping other speakers into it did not help matters. It's the shallow cabinet design. You simply cannot make an a cab that size produce good bass response. Tubes? Nope, swapped those out at as well, only resulting in differing amounts of preamp gain.

So now that I no longer have this amp, and have no need to lie to myself about how "good" it was, I can now say that it's a terrible amp. Second place: The Vox Night Train NT-15. I tried to love that amp also. Sounded terrible.
I had the same experience with the same amp. I had an AC10 that I loved -- I upgraded the speaker and the tubes -- but it died. Right now I'm just using my vintage Harmony Amp, which is awesome. Eventually I think I'm going to get myself a Katana as a second amp.
 

KeithDavies 100

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As others have said, Vox amps have their own sound(s), and they're not the same as Fenders, Marshalls, Boogies etc.

I have a '63 Vox AC30 which is the most sublime thing to play through cranked, but I haven't played in bands for a while and there's just no way I could use it at home.

I bought an AC4 1x12 to try and get some essence of that sound at usable home volumes, and - for me - it doesn't do a bad job. I love mine, and loved it enough to invest in a Celestion Blue speaker for it - cost more than the amp did, I think! - and it's great.

But perhaps it depends what sound you're chasing. Like I said, it's not a Fender or a Marshall.

There's a YouTube video though - I'll leave people to search for it if they're interested - in which a guy demonstrates the significant range of tones available from the apparently limited controls. I was impressed, but again it perhaps depends on expectations, or what you're chasing.
 

G Stone496

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For several months I refused to say it, because I spent my hard-earned $$ on one (beige). It look great. Sounded terrible. And the ironic thing was that I thought I was moving up from my AC4TVH, but that amp actually sounded better. So for the longest time I forced myself to embrace the trebly tone with absolutely no bottom end, and (probably) decent mids that were simply stomped all over by the treble.

The problem: not the 12" speaker, swapping other speakers into it did not help matters. It's the shallow cabinet design. You simply cannot make an a cab that size produce good bass response. Tubes? Nope, swapped those out at as well, only resulting in differing amounts of preamp gain.

So now that I no longer have this amp, and have no need to lie to myself about how "good" it was, I can now say that it's a terrible amp. Second place: The Vox Night Train NT-15. I tried to love that amp also. Sounded terrible.
Haven’t never tried one of those before yet.

I got a Vox AC4HW1 Handwired 4 watt 1x12” though and like it a lot. Gots chime in spades with a solid bottom too and breaks up very nicely.
 
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Sax-son

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Some of the original Vox AC' came equipped with those Sola Sound alnico speakers which were heavenly sounding in my opinion. I was trying to buy one from this one guy, but he wanted so much money for it that I had to pass. Those were the ticket in my view.
 

Sax-son

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I love mine, and loved it enough to invest in a Celestion Blue speaker for it - cost more than the amp did, I think! - and it's great.
I think you have to treat the speaker choice like a separate component unto itself and not get hung up on the cost factor there. They are separate from each other and can enhance the tonal quality of the amp. The folks who build the amps rarely build the speakers.
 

Dukex

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I went back and forth at the store for like an hour between the AC4C1-12 and AC4C1-BL back when I bought my amp (the AC4C1-BL).

In the store I could tell that the 12” speaker had noticeably more low end than the 10” speaker in the blue. I bought the blue 100% because it was cheaper, and I’ve wished many times over the last 6-7 years that I had gotten the 12.

However, I just swapped in a Celestion Greenback in the blue and the low end it does have is considerably tighter now. At some point I may make an extension cab with a bigger box to put the original speaker in. But the Greenback will definitely make me happier until I save up for a bigger amp.
I ended up trading mine in toward an AC4HW1 (greenback). Not because I didn't like it but because I did like it and wanted to step up to the top-of-the-line model. I played my AC4C1-BL through an oversized oak cab loaded with a 10" Weber AlNiCo, and the amp came alive.

Both the original small cab and stock speaker are what holds it back IMO. In other words, I wouldn't build an extension cab and put the cheap stock speaker in it. I'd put the greenback in the bigger cab (you won't be sorry) and put the cheapie back in the tiny cab. Or keep the GB in the original cab and put a 10" Weber Blue Pup only ($129) in the larger extension cab.
 
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TonyClark

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As others have said, Vox amps have their own sound(s), and they're not the same as Fenders, Marshalls, Boogies etc.

I have a '63 Vox AC30 which is the most sublime thing to play through cranked, but I haven't played in bands for a while and there's just no way I could use it at home.

I bought an AC4 1x12 to try and get some essence of that sound at usable home volumes, and - for me - it doesn't do a bad job. I love mine, and loved it enough to invest in a Celestion Blue speaker for it - cost more than the amp did, I think! - and it's great.

But perhaps it depends what sound you're chasing. Like I said, it's not a Fender or a Marshall.

There's a YouTube video though - I'll leave people to search for it if they're interested - in which a guy demonstrates the significant range of tones available from the apparently limited controls. I was impressed, but again it perhaps depends on expectations, or what you're chasing.

I'd love to hear that old '63 cranking out some tunes Keith. (by the way, I miss going to hear your brothers Ray and Dave rocking back in the day! ;))
 
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