Small combo + attenuator

[Hardrocker77]

Hello everyone, i need your help!!

I have a small 4w valve combo amp, a VOX AC4C1-12.
While I can have a good clean sound at low volume, I really cannot drive the amp without being too loud. Even with the master volume almost closed.

Few days ago I saw this Bugera passive attenuator, it has a reasonable price and the reviews are good. And It's compatible with 16 ohm.
https://www.youtube.com/watch?v=fBTeG9csjRQ

I would like to add to the back of the amp 1 female output and 1 female input (like an effect loop). They will disconnect the segnal between the amp and the speaker. Than I can connect an attenuator, or just reconnect the speaker with a small cable if i don't need to use any attenuator.

The speaker is connected by 2 cables with blade connectors.
I need to connect the 2 cables to a female 1/4 output jack.
Then i need a to connect a female 1/4 input jack to 2 speaker cables with female blade connectors.

It's my first DIY work and I know nothing about eletronics, I would like to know if I'm not missing anything.
Thank you!!

 

[Hardrocker77]

Re: Small combo + attenuator

Today i realized the amp has already an external speaker output, so I will only need to return inside the amp. It would cut half of the work.
Any thought?

 

[PierceOkken]

Re: Small combo + attenuator

So are you attempting to add an effects loop? Or just a space after the power amp and before the speakers?

 

[Old Guy]

Re: Small combo + attenuator

Passive attenuators tend to squish your sound as you lower the volume.

 

[Hardrocker77]

Re: Small combo + attenuator

So are you attempting to add an effects loop? Or just a space after the power amp and before the speakers?

If I'm not wrong the attenuator goes between the las t signal of the amp (power amp?) and the speakers.

to old guy: I will check into it. I need a cheap (under 150 €) attenuator or i'm not gonna ever hear the natural overdrive of the amp. It's not worth to spend more, becouse in that case I could just sell the amp and buy a different one.

 

[FuseG4]

Re: Small combo + attenuator

He wants to have the speaker cables from the amp and speaker cables from the speaker both on 1/4 jacks so he can plug attenuator in.
Basically what you have now is an external jack *that automatically defeats the internal speaker* so not easy to use with the power soak, and it's a closed back cab so I see why he wants the amp speaker to have 2 normal jacks to place the attenuator, instead of the internal-defeating single "extension speaker" jack.

Here's what I would do.
Remove the back panel. Replace their speaker defeating jack with a normal 1/4", just the two wires coming from the amp chassis to the jack. Pay attention to which was + and - originally, and preserve that.
Then from your speaker the + and - from the speaker can either be either put on a 1/4 female jack, or I would just attach a male plug to the ends coming off the speaker, and drill a hole in the back panel it can fir through.

That as long as it's cord is long enough, when you use just the amp, plug the male plug from the speaker into the 1/4 jack from the amp chassis you installed. no separate cable needed.
When you use the attenuator, you plug a separate speaker cable from the amp 1/4 female jack to the attenuator, and then the male plug from the speaker goes to output of the attenuator. Saves you a speaker cable vs having two female 1/4"

 

[FuseG4]

Re: Small combo + attenuator

And yeah, I stopped using my attenuator, it was a passive rheostat type like the one above.
Well, I burnt mine out feeding it too much wattage. But the sound was... OK. But you'll have to crank it way down to dime the amp in an apartment, and the interaction with the amp really goes down and so does the treble.
Also many amps don't sound as good when you just hear the tube breakup without the speaker and volume smoothing it out, many small amps will sound very splatty and unrefined, and fizzy.
These days I use an eminence FDM speaker that is an attenuator built into the speaker. Sounds better to me, but everyone has a right to experiment with the small amp plus attenuator combo. For some people it works.

Shame yours is closed back, I would really recommend the speaker I use. Sounds kind of like a celestion, but quieter! But you need to be able to reach the knob on the back. Turned my 22W amp into 6.25W. So I can turn my amp up to 4 or 5 for everyday chilling/practice/jamming, when it used to sit on 2 or 3.

 

[PierceOkken]

Re: Small combo + attenuator

Oh, gotcha. I have done this. I used a JHS little black box between an amp head and cab. The tone difference was noticeable, it was not bad, but it just wasn't what I liked. I ended up going to a real attenuator (riviera rock crusher series) and that's what I use now. Passive attenuators work ok, but they aren't great. An actual load box is more expensive but it will work way better.