Attenuating question for Blues Deluxe RI combo

greggreg66

I've recently managed to resurrect my long 'broken' Blues Deluxe Reissue by using a repair kit from Keld Ampworks and also putting in a new reverb tank. It's been about 9 years since this amp worked and I forgot the about crazy loud jump in volume from naught to deafening in the tiniest of turns on the volume knob. 

As Christmas is approaching, I am pondering putting on my Christmas list (yes I am a 40 year old man) either a JHS Little Black Amp Box (or the self-build kit from Keld) which goes into the effects loop or perhaps a Bugera attenuator between the amp and speaker. My understanding (I could be utterly wrong) is that the effects loop volumes just affect the pre-amp valves, whereas the attenuator controls the power amp ones. Does that mean I could get a better 'cranked' tone at sensible volumes with the attenuator or is an effects loop volume just as good? I really don't know which is 'better'.

I can appreciate that the Bugera attenuator might be a bit budget as far as attenuators go, but I'd like to keep within a reasonable Christmas present budget : )

Thanks in advance for responses!

DrCornelius

Have you looked at the Lion Tamer ? I had one for an HRD and it worked really well 

greggreg66

DrCornelius said:

Have you looked at the Lion Tamer ? I had one for an HRD and it worked really well 

I hadn't to be honest. I imagine it might be similar to the JHS one but in a much smaller package? Just watched a YT demo of one and it looks/sounds great

bertie

I used to use a home-made equivalent of the black box ( known as the HRDx volume box, cost me about a £10 er in parts)  with a deville - use to tame the clean channel make it  "controllable"  and more usable -   seemed to add something to the ODs but that's probably just "in my head"

as you say - an attenuator it is not, and you're not cooking the power valves any more.  -  I never used an attenuator with the deville, but I do use a hotplate with my chubster 

ICBM

It's absolutely true that the FX loop 'volume box' only allows you to drive the preamp valves harder, not the power valves. To drive the power valves harder you need a 'true' (power) attenuator.

However, many people find that the preamp type works very well, is much cheaper and more convenient, and doesn't wear out the power valves like a power attenuator does, so if you don't have either and you're unsure which to buy, I would try that first. The Lion Tamer is highly recommended!

A power attenuator is also a bit of a pain to use with one of these since the speaker cable is nowhere near long enough - you'll need to use an extension cable or replace the combo's one with a much longer one so you can sit the attenuator on top of the amp.

There's also no reason you can't use both together if you ever want to - that would allow to balance the preamp and power amp overdrive as you want. I've never tried it with one of these amps, but it can work very well with the reissue non-MV Marshalls with a loop.

Funkfingers

The problem with the early Blues Deluxe, Hot Rod Deluxe and Hot Rod Deville amplifiers is the linear taper pot at the beginning of the signal path.

The popular modification was to change to audio/logarithmic taper. Eventually, Fender integrated this into the circuit themselves. (HRDx mk3.)

greggreg66

ICBM said:

... if you don't have either and you're unsure which to buy, I would try that first. The Lion Tamer is highly recommended!

Thanks ICBM. I think this is the most pertinent point for me and probably the best start. 

Funkfingers said:

The problem with the early Blues Deluxe, Hot Rod Deluxe and Hot Rod Deville amplifiers is the linear taper pot at the beginning of the signal path.

The popular modification was to change to audio/logarithmic taper. Eventually, Fender integrated this into the circuit themselves. (HRDx mk3.)

Yeah I did wonder that also! I suppose it's not impossible to change the volume pot still. I got the amp (new) in early 2007 I think, not sure which mk of amp that makes it, but I guess I can test the pot to see if it's linear or not. 

ICBM

Even when they changed it to log (or actually Audio), it's a 30% taper from what I remember... I don't know why they don't just do it properly and use a 10% one. Presumably the 'demo factor' - "wow, this is really loud and it's only on 3!" - overrides being able to get a useful range on the control for proper use...

Either way, the Lion Tamer or other volume box is more effective than changing the amp's pot even for a true 10% log, since it comes at a later point in the circuit after which there is no further compression unless the power stage is cranked into overdrive. It's also *much* easier than changing the pot, which is a bit of a faff as it needs to be a very specific type to fit the PCB, which has to come out fully to get at it.

greggreg66

Yeah it’s definitely a bit of a faff getting at those pots. I changed the usual suspect resistors and started by trying to remove the PCB. If there’s not too much benefit to that then I definitely won’t bother! 

Funkfingers

ICBM said:

*much* easier than changing the pot, which is a bit of a faff as it needs to be a very specific type to fit the PCB, which has to come out fully to get at it.

"Special" PCB mount pot with two extra "legs" to secure it in position. Solid shaft to accept the fastening screw in a chicken head control knob.

ICBM

Funkfingers said:

"Special" PCB mount pot with two extra "legs" to secure it in position. Solid shaft to accept the fastening screw in a chicken head control knob.

Not two - it has a metal bracket/frame with four legs. The spacing of the pins is of course important...

Not unobtainable, but harder than a standard PCB-mount pot.

If absolutely necessary, you can sometimes remove the frame from a broken pot and re-attach it to a new one - it's held on by the tabs that hold the normal pot casing to the bushing part.

barnsleyboy

greggreg66 said:

As Christmas is approaching, I am pondering putting on my Christmas list (yes I am a 40 year old man) either a JHS Little Black Amp Box (or the self-build kit from Keld) which goes into the effects loop or perhaps a Bugera attenuator between the amp and speaker.

Nothing wrong with a Christmas list, I'm 55 and every year the 59 Gibson LP goes on the list ..... one day it will be mine!

I have a Peavey Classic VTX which is earth shatteringly loud, I use a Donner Emo amp controller pedal in the effects loop. Great build quality for about 20 quid, and works really well. I looked at the JHS and it seemed a bit expensive for what it was. I then looked at building something myself, and for £20 the Donner was a no brainer.

The pre-amp on the Peavey is solid state, but still produces some great tones. I'm toying with buying the Harley Benton PA-100 attenuator to introduce a bit of tube distortion into the equation. It seems to be a clone of the Jettenuator which I sold on a while back (should have kept it really). Again, I looked at building a DIY attenuator (plenty of how to videos online) but adding up the parts and comparing to the PA-100 was another no brainer. Couple that with a 12 month warranty included on the HB!!