Simple question about Quilter SuperBlock US

[Jazz_175]

Hi,
I am considering buying a Quilter Superblock US but I do not have a speaker-cabinet.
However I have a Fender Deluxe Reverb, which is not working properly at the moment (I should take it to a tech, maybe it's time to change tubes).
I was wondering if it is possible to attach the SuperBlock to the back of the Fender Amp by unplugging the speaker from the Fender Amp (there is a simple jack).
Does it make sense or is it not recommended?

[chris32895]

You're essentially just plugging the amp into a speaker. A combo amp is just an amp head and speaker in a single cabinet. So, you are just bypassing the the actual Fender amp to get to the speaker. Do you know the speaker impedance? I think they are 8 ohms but you would need to verify that else you could screw your speaker up. Good news is the Quilter is rated ideally for 8 ohms but will accept between 4-16. If it were me I'd try to keep to manufacturer specs. Seems they should match, though.

I personally have a Fender Champ 20 and if I were to get a different amp I would just do what you're doing and reuse my cab and speaker and get whatever head I wanted.

Anyone please correct me if I'm wrong as I don't want to screw anyone's gear up!

[omphalopsychos]

Yeah that will work.

Unplug the speaker from the chassis and plug it into your quilter block.

If the speaker cable isn't long enough you can get one of these:

[Jazz_175]

Thanks for the replies.
It's not quite clear to me where do those red and black connections in the picture go.

[omphalopsychos]

Thanks for the replies.
It's not quite clear to me where do those red and black connections in the picture go.

They go onto the back of the speaker on the lugs.

Here are a couple of pictures to illustrate.

Without connectors:


With connectors:

[sgosnell]

I've been playing mine through my dead Vibrolux Reverb for some time. It's the best match I've found, it sounds great. I made an adapter, with two endpin jacks wired together, and plug the speakers into it using the existing speaker wires and the same plug. I plug a regular speaker cable into the other end, and to the amp. Works fine. Or a speaker cable with a female 1/4" inline jack on one end will work. Whatever makes the connection.

[nevershouldhavesoldit]

Do you know the speaker impedance? I think they are 8 ohms but you would need to verify that else you could screw your speaker up.!

You won’t harm the speaker. Too low a load impedance can harm an amplifier because the current required to maintain a given output wattage is inversely proportional to the load resistance. An amp that can’t pump enough power into low impedance loads can overheat and take out its power supply or output devices.

[Jazz_175]

I wonder if something like the following adapter would work to make the connection.
Rockboard Mini Mounting MOD TRS – Thomann Italia

I've been playing mine through my dead Vibrolux Reverb for some time. It's the best match I've found, it sounds great. I made an adapter, with two endpin jacks wired together, and plug the speakers into it using the existing speaker wires and the same plug. I plug a regular speaker cable into the other end, and to the amp. Works fine. Or a speaker cable with a female 1/4" inline jack on one end will work. Whatever makes the connection.

[bluenote61]

I recommend to check at first whether the speaker cable is long enough to get the Quilter connected. IMO you don't need that Rockboard item. A simple adapter with 2xfemale coupling will do the same job, if the speaker cable of the amp would be too short.

[sgosnell]

I wonder if something like the following adapter would work to make the connection.
Rockboard Mini Mounting MOD TRS – Thomann Italia

That should work. Fender amps, at least the ones I've seen (and I haven't seen every model up close) have a standard 1/4" plug coming from the speakers, which plugs into the amp speaker output. This could plug into the Superblock, except that it's probably too short to reach it. Anything that will allow getting that plug into the Superblock will work. I made my own adapter, because I had parts on hand and I was comfortable doing the work. The linked device should allow plugging the speaker plug into it, and also a standard speaker cable with a plug on each end. Whatever gets you from the Superbock speaker output to the speaker(s) will work.

[bluenote61]

I wonder if something like the following adapter would work to make the connection.
Rockboard Mini Mounting MOD TRS – Thomann Italia

This will do the same job and it's cheaper. But, as I wrote above check the length of the amp's speaker cable first whether it's long enough.

the sssnake 1802 Adapter

[Jazz_175]

Thanks, I've just come back home with an adapter exactly like the one you suggested. I went to an electronic devices shop to buy the adapter because the lenght of the speaker cable is too short.

This will do the same job and it's cheaper. But, as I wrote above check the length of the amp's speaker cable first whether it's long enough.

the sssnake 1802 Adapter

[pingu]

This will do the same job and it's cheaper. But, as I wrote above check the length of the amp's speaker cable first whether it's long enough.

the sssnake 1802 Adapter

be sure to use speaker cable with that
and you’ll be fine

(not a guitar instrument cable , as the central core conductor is too thin to carry the current required)

[Jazz_175]

be sure to use speaker cable with that
and you’ll be fine

(not a guitar instrument cable , as the central core conductor is too thin to carry the current required)

Do you mean that a speaker cable should go from the SuperBlock to the adapter?

[bluenote61]

Do you mean that a speaker cable should go from the SuperBlock to the adapter?

Yes.

[nevershouldhavesoldit]

Do you mean that a speaker cable should go from the SuperBlock to the adapter?

You need “speaker cable” with 2 conductors the same size (at least 18 gauge for amps making more than a few Watts) from amp to speaker.

The 25W output from a SBUS will pump a hair over 1.7 Amperes through an 8 Ohm speaker and the plugs & jacks & wires connecting it to the amp, which would be enough to blow the power fuse in some amps. So 1.7A is enough current to take seriously here.

Instrument cable has a very thin center conductor (24 gauge in most garden variety cords) and a ground shield of very fine wire - the strands are usually around 35 gauge when braided and about 45 if spiral wrapped. A steady flow of even 1A (8W through 8 Ohms) is too much for cable that thin to pass without loss to heat because of its resistance - it’s a tiny little toaster. And that heat is energy lost from the signal - so 8W out is a bit less than 8W at the speaker.

You won’t hear a difference that small, so it won’t affect a SBUS used at bedroom volume. But a Twin used on stage could heat a cheap instrument cable used as speaker wire enough to damage the insulation between center conductor and ground wrap. If this happens at either plug end where that insulation may already have been damaged by soldering, a short can develop. You really don’t want to short circuit that output. And more than a few feet of 24 gauge wire between a big amp and its speakers can audibly affect output levels. Feel your speaker wires in the middle of a gig. If they’re hot, they’re too thin.

Yes, the wire from speaker terminals to the voice coil is thinner than 18 gauge. It’s bare copper and it’s cooled by the air moving around it from cone motion. But it is a tiny resistor, it does turn a tiny bit of power into heat, and I’ve always wondered why it isn’t heavier.

Use proper speaker cable. It’s not expensive - you can make or buy it for a few dollars. If the wire in the amp is too short, replace it with a longer piece of 18 gauge zip cord for $1.