Talk me out of/into a VOX AC30 (and some dB discussion)

Discussion in 'Amp Central Station' started by Polderpatat, May 22, 2019.

  1. TokyoPortrait

    TokyoPortrait Tele-Holic

    Posts:
    722
    Joined:
    Dec 10, 2017
    Location:
    Tokyo, Japan
    Well, I just tried at 1 metre with the same phone app meter. I should add, same as yesterday, the amp was up on a wooden chair, cone approx 65cm off the floor.

    That same (or, similar) definitely clean 'Here Comes My Girl-ish' 65dB sound of yesterday was around 76dB today, peaking around 84.

    Various versions of the nice juicy 'clean' I like were around 79dB - 81dB and peaking 85dB.

    Nothing got over 85db, regardless how how cranked. It always topped out there. This compares to the 84dB yesterday at 2m.

    So, peaks gained around 1dB at 1m. At 1m the averages increase ranged from about 11dB for 'Tom sound' to around 6dB for the rest.

    But, here's something I noticed. Today, standing a bit closer, it seemed loud. That seems reasonable, as I was closer. However, I mean loud enough that my ears hurt a little and I didn't want to play too long that loud and that close (facing across the front of the cab with left ear closest and in line with the left edge of the cab and about an arm's length from it). That ear was still a little sore some 40 minutes later. It's calmed down in the last 20 mins.

    So, I reckon that dB meter was worth the price, in the sense that being free it is also worthless. I just looked and various sources say 85 dB is the equiv. of a busy street / vacuum cleaner / noisy restaurant / cello or violin / etc. And, 75 is a toilet flushing. No way I was that quiet.

    So, in the end, all this proves is that I know nothing. I have a mental image of Ygritte talking to me...
     
    Polderpatat and telemnemonics like this.
  2. Old Deaf Roadie

    Old Deaf Roadie Tele-Holic

    Posts:
    553
    Joined:
    Oct 11, 2017
    Location:
    Oregon
    To put things into perspective, I mix worship teams & traditional jass bands at about 85 db, entire club bands at about 90 db. You are producing those levels, albeit with an uncalibrated measuring device, all by yourself. You don't need an amp, you need headphones.
     
    MilwMark likes this.
  3. 3-Chord-Genius

    3-Chord-Genius Poster Extraordinaire

    Posts:
    5,742
    Joined:
    Apr 3, 2015
    Location:
    Winchester, VA
    Yeah, I've noticed that there seem to be a few on the used market and they're not expensive as I expected. Sort of like 4X12 cabinets... people buy those and realize it's too much...
     
    Mad Kiwi likes this.
  4. gusfinley

    gusfinley Tele-Holic

    Posts:
    651
    Joined:
    Jun 11, 2014
    Location:
    SLC, UT
    Yes. The AC4C1 series amps are single-ended and do not have the same kind of master volume as the CC and C series Push-pull amps. For some reason, the AC4C1 designers decided to put a "bright" cap across the master volume. Bright Caps are not inherently evil, one does exist on the "volume" (gain) control on the classic top boost circuit. The bright cap passes high frequencies past the volume control when it is not in its max position. The farther you are from the Max position, the more effect that the bright cap has on the tone.

    On a Master Volume, this is a bad thing as it allows your master volume to also act as a tone control. Using a vox analogy, this would be like putting your "cut" control and master volume on the same knob, so that when the volume is raised so is the 'cut' control - which cuts out high frequencies.

    Some like to snip the bright cap on the Vox amps channel volume (gain) control so that it works better with effect pedals.

    In my opinion, the bright cap on the master volume (c20) is out of place and should be removed. It is not hard to do either. I was being lazy and just grabbed it with some needlenose plyers and wiggled it back and forth until the leads of the cap broke off. Some finger nail clippers would work great, too.

    I had heard a lot of tdpri members who have not liked the AC4C1 series amps, but many like the AC10. My theory on this is that tele players who play this bright guitar into a top boost circuit amplifier at low gain and low volume settings are hearing the effects of all of this "brightening" circuitry. On the AC10, the master volume exists right before the power tubes and does not have a significant effect on tone at lower volumes- so you hear a truer representation of the signal at all volume levels.
     
    OldDude2 likes this.
  5. OldDude2

    OldDude2 Tele-Meister

    Age:
    60
    Posts:
    355
    Joined:
    Jun 27, 2018
    Location:
    Nashville, TN
    Gus - Awesome I've been struggle to find that sweet a spot and have considered moving the amp.

    Before I cut anything I'll post pictures thank you!
     
  6. Polderpatat

    Polderpatat TDPRI Member

    Age:
    22
    Posts:
    10
    Joined:
    Aug 7, 2017
    Location:
    Belgium

    First thanks for the input and measurements :)
    secondly I know these apps are far from great, but at least it can be used as a somewhat consistent measuring tool that, although many parameters can influence the end results, is just a bit more meaningful than people saying yeah it's crazy loud. :p
     
  7. Polderpatat

    Polderpatat TDPRI Member

    Age:
    22
    Posts:
    10
    Joined:
    Aug 7, 2017
    Location:
    Belgium
    what do you mean "you should use headphones"? why?
     
  8. Old Deaf Roadie

    Old Deaf Roadie Tele-Holic

    Posts:
    553
    Joined:
    Oct 11, 2017
    Location:
    Oregon
    At 85-90 db, one player can be heard throughout the neighborhood. With cans, you get all the intensity while preserving the peace. I work a room every single day where clarity washes out at 98 db. If the guitarist is taking up 85-90 db by himself, it leaves little room for the rest of the band resulting in not running the guitar in the mix at all, and mixing the rest of the band around them. It sounds as if you enjoy intense guitar volumes. Headphones can help with that.
     
    MilwMark likes this.
  9. Polderpatat

    Polderpatat TDPRI Member

    Age:
    22
    Posts:
    10
    Joined:
    Aug 7, 2017
    Location:
    Belgium
    @Old Deaf Roadie the thing I mostly enjoy at "higher" volumes is that it really fills the room :)
     
  10. Les H

    Les H Tele-Meister

    Age:
    45
    Posts:
    389
    Joined:
    Jun 2, 2018
    Location:
    Kansas
    I love the vox sound and would never try to talk anyone out of an AC 30.

    But....

    If your not playing out and don't plan on playing out I would go the AC 15 route myself, for a little extra they have a 212 AC 15 as well. The 30 watt Vox is a stage amp and louder than a comparable 30 watt amp like a PV Classic 30.

    But if you foresee joining a band in the future than by all means get one.
     
  11. Mad Kiwi

    Mad Kiwi Friend of Leo's

    Posts:
    2,306
    Joined:
    Nov 17, 2009
    Location:
    Land of the Long White Cloud
    It was a CC - 1x12 Blue (Ac15cc1x ?)
     
  12. Old Deaf Roadie

    Old Deaf Roadie Tele-Holic

    Posts:
    553
    Joined:
    Oct 11, 2017
    Location:
    Oregon
    I get that. Some guys like to feel it. I just can't be around it anymore. I have lost 75% of my hearing, much of it due to loud music.
     
  13. alathIN

    alathIN Tele-Holic

    Age:
    54
    Posts:
    583
    Joined:
    Oct 25, 2017
    Location:
    Indiana
    I was going to say the same thing.

    It's a post-phase-inverter ice-pick rounder-off-er.

    I have a Trinity TC-15, which is based on the AC 15. I like to dial it in to a spot that is a bit too ice-picky, then use the cut to smooth that off. You can get all the bright without the pain. I'm surprised more amps don't have this knob - a lot of Fenders could use it.

    I'll give one scenario where I'd maybe go against the "AC30 is too much" flow - which is 99.9% correct IMO - but if you want super clean AND loud with plenty of head room, it might be just the thing.
    When people say Vox amps don't do dirt pedals, my sense is they're saying driven/distorted/crunchy Vox tones don't mix with most pedals. If you keep your Vox clean, it'll do dirt pedals just fine.

    But part of the magic of Vox is all the subtle shades of breakup you start getting before the point of of actual distortion.
    If you try to do those tones at home with an AC-30, you'd better consult a structural engineer first.
     
    VWAmTele and TokyoPortrait like this.
  14. 3-Chord-Genius

    3-Chord-Genius Poster Extraordinaire

    Posts:
    5,742
    Joined:
    Apr 3, 2015
    Location:
    Winchester, VA
    I had an AC4-TVH and did the bright cap mod, as well as replacing another cap with one of a larger value. The amp sounded decent after that, especially in a band. Later, I got an AC4C1-12 which I thought would sound better due to the 12" speaker, but the cabinet was so shallow that the amp was severely lacking in bass. I eventually ended up with an AC10C1 which is my only amp now, and I gig with it.
     
  15. alathIN

    alathIN Tele-Holic

    Age:
    54
    Posts:
    583
    Joined:
    Oct 25, 2017
    Location:
    Indiana
    Yes. Vox watts are different. You have to multiply by two or maybe three.
    Unless you need crystal-clean... maybe.

    I put a variable power knob on my TC15 that goes from about 0.5 to 15 watts.
    For home use, I almost always have it on 0.5
    And when I flip to the EF86 channel, I also use a Weber attenuator.
     
  16. gusfinley

    gusfinley Tele-Holic

    Posts:
    651
    Joined:
    Jun 11, 2014
    Location:
    SLC, UT
    Well, the AC15CC1X varied from a true AC top boost circuit by:

    1) Omitting the cathode follower and driving the tone stack from the plate of the second gain stage to save having to put another tube in it.

    2) The plate load resistor on the input stage was 100K instead of the original 220K. My AC30CCH didn't sound right until I swapped my 100Ks ( one for normal and one for top boost ) with 220Ks. 100ks sound like a Marshall - 220Ks sound like a vox or orange.

    Perhaps this led to your dislike of the gainier settings....
     
  17. ce24

    ce24 Poster Extraordinaire

    Posts:
    5,180
    Joined:
    Jan 26, 2008
    Location:
    Idahoastan
    But it has a MV. my AC25 C2 twin is great at home or in my band.
     
  18. Mad Kiwi

    Mad Kiwi Friend of Leo's

    Posts:
    2,306
    Joined:
    Nov 17, 2009
    Location:
    Land of the Long White Cloud
    I really liked the amp EXCEPT, the core crunch sound had a very weird tone to it. It got crunchy really well, nice and early which was what I had heard would happen with a 15 but the tone was weird, sort of irritating. I think it was a very high mids VERY focused crunchy sound. I've never heard it before, in any amp models or the many various range of amps I have played with.
     
  19. Norris Vulcan

    Norris Vulcan Tele-Holic

    Posts:
    544
    Joined:
    Aug 7, 2015
    Location:
    Somerset, UK, Europe
    This is exactly it. Headroom.
     
  20. gusfinley

    gusfinley Tele-Holic

    Posts:
    651
    Joined:
    Jun 11, 2014
    Location:
    SLC, UT
    Nice AC30CC2X for sale locally for $800!!

    To bad it's too much amp for me down in my dungeon............
     
IMPORTANT: Treat everyone here with respect, no matter how difficult!
No sex, drug, political, religion or hate discussion permitted here.


  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.