Converting a Vox AC4TV 10"" guitar amp into a Bass amp?

recreate.me · #1 10-06-2010, 12:08 PM

So i have a Vox AC4TV amp, Shown on there website Its a great tube amp at 4 watts with an attenuator built in.

The thing is i never use it for guitar and really want to get rid of all my guitar stuff to focus on bass. Would i be amp to simply remove the 10" guitar speaker thats in it, and replace it with a 10" bass speaker at the impedance ?

I know the fact that its closed back can cause speakers to tear, but as a low volume practice amp would that effect really matter?

Also this amp only has a Vol, and a Tone knob. Would the tone knob really only effect the 'high' end on the bass and let the low end pass through, or would it cut the low end?

Would this be fixable with an EQ pedal ?

Thanks for the help guys!

KramerBassFan · #2 10-06-2010, 12:54 PM

Just try using a bass through it right now.

Its only 4 watts, any way....

recreate.me · #3 10-06-2010, 01:19 PM

I have in the past, and its really treble heavy. It also breaks up really easy, and when i go back to playing guitar through it i feel like its breaking in a lot, maybe a bit to much.

At 4 watts it actually gets really loud.

RickenBoogie · #4 10-06-2010, 04:47 PM

That's because it's a guitar amp. If you're getting rid of all your guitar gear, get rid of the AC4 too. Use a bass amp for best results, a bass speaker in a guitar combo rarely ever works out well. It is a great little guitar amp though, I have one and use it often for home pickin'.

D.M.N. · #5 10-06-2010, 04:55 PM

You could always take the amp out of the enclosure it's self, and build it its own little box to be used as a standalone amp through a proper bass enclosure. However, it's 16 ohms, so it may be difficult to find a bass enclosure at that rating nowadays.

will33 · #6 10-06-2010, 04:57 PM

I'm off in the valve jr. world but I like the sound of those little Vox's too. Couple things.

1. I don't think/don't know if they're cool with any other output than 16ohms. That means you'll likely end up with a 2 speaker combo of some sort.

And 2. If you can find a speaker that'll work and seal up the back of the cab if it's not already, it ends up to be too small a unit to get much bass out of.

I like the way my VJ sounds through a 210 bass cab. It's fun. I'd say try disconnecting the internal speaker and hooking it up to whatever bass cabs you have and see what you think but keep in mind the 16ohm thing, may have to wire up a series cable. And yeah, it's 4 watts, it's for recording or playing at home. Ignore the lack of volume and concentrate on getting some sweet tones, they're in there.

recreate.me · #7 10-06-2010, 09:59 PM

Well it is a closed back combo, i was thinking of buying a Jensen MOD10-35 speaker, they advertise as a Bass speaker and a guitar speaker... and a 35 watt speaker seems good enough in a 4 Watt combo....

I was curious if playing bass through it would damage the circuitry of the amp itself, like is it set up to cut out that bass, so forcing it through can damage things? or would be only if i play it at high volumes?

D.M.N. · #8 10-07-2010, 12:30 AM

Nope. The amp won't be damaged.

will33 · #9 10-07-2010, 08:25 AM

Quote:

Originally Posted by recreate.me

Well it is a closed back combo, i was thinking of buying a Jensen MOD10-35 speaker, they advertise as a Bass speaker and a guitar speaker... and a 35 watt speaker seems good enough in a 4 Watt combo....

I was curious if playing bass through it would damage the circuitry of the amp itself, like is it set up to cut out that bass, so forcing it through can damage things? or would be only if i play it at high volumes?

The only thing that could be damaged is the speaker. Even that's not very likely with 4 watts.

Hawkbone · #10 02-03-2011, 09:59 PM

Found this while researching mods for my son's AC4TV8. Vox AC4TV Basically, this dude says 8ohms is cool, but a few mods will make it foolproof at 8ohms.

Also found this thread on my search so thought I'd update it with the info I found.

If anyone tries their AC4TV with an 8 ohm bass cab, please post the results here. I'd be interested in how that works out. I'd try it on my 210 but but I'm not going to experiment with my boy's only amp.

baldy McBalders · #11 02-03-2011, 10:05 PM

Hi.
Sorry if this formats strangely; typing it on my phone.
I have a bugera v5 guitar amp that I am using very successfully as a little bass amp. Spend $15 or so and replace the 12ax7 preamp tube with a 12ay7. Made all the difference for me, as it is lower gain and provides a bit more pre headroom.
And yes, an eq of some sort helps. Sounds yummy for me.
B.

BassJunkie730 · #12 03-15-2011, 07:01 AM

I just got an ac4tv. After a little poking around looks like you'll need to do a few simple things.

Change C5 to a higher value 22nf should be enough.
Drop in a 5751
install a screen grid resistor by cutting a trace and attaching a resistor to the back of the board to keep the tube running cooler.

Then internally brace the cab and fill with batting to help with the boxiness. Then install an 8ohm speaker that is designed to fit into a very tiny sealed cab.

Lastly if you want to use the attenuator beef up the resistors to 5watt- maybe 10watt.

The output tranny on this is BIG. Bass will not be a problem.

Of course the cab and speaker and attenuator mods are unnecessary if you use an 8ohm cab on the "4watt" setting.

I've successfully modded a valve junior and sold it to a TBer. That OT was TINY. It needed the tranny mod.

The Ac4tv doesn't.

Mercury mag is just trying to take your money with their "improved trannies" on this amp.

Here's a comprehensive thread at Vintage amps forum

http://www.vintageamps.com/plexiboar...f0fde461af0176