Does Power Scaling / VVR deliver ?

Telejester

Best gtr and amp combo i ever heard is a tele used with a jtm45, its the sound in my head. Be it for playing out or home playing with grouchy neighbours next door meaning amp volumes have got to be seriously low, does power scaling / vvr deliver ?

A jtm45 type head with an fx loop and power scaling seems to be the answer on paper, but in reality....what do you think ?

bazxkr

Don't know about the JTM but I've got a Blackheart BH5 mini stack and had the Marshall class 5 both RAT modded with the OPR power scaling feature etc and they were both excellent at getting the cranked tone at low volumes. So for me, Yes.

fretmeister

Worked very well in the Badger 30 I had.

monquixote

Fender Bass breaker 45

ICBM

I doubt this will be a popular opinion but I would say no.

To me, it doesn't sound as good as a well-implemented standard master volume - every amp I've tried with both has sounded better with the power scaling up full and the master low, not the other way round - and it doesn't sound as good an attenuator after the amp does either - because the power supply is still not working as hard so you don't get the proper compression.

For a JTM45 I would go for a post-phase-inverter MV mod or a Powerbrake - or both.

John_A

A Marshal Powerbrake works very well with a JTM45, they are cheap second hand, and you don't heed to mod your amp

Collings

I was originally using a jtm45 with a thd powerbsoak but was never really happy and my local tech suggested a ppiv master volume so i gave that a try and it works really well and sounds far better than using a powersoak. I can,t imagine power scaling being much better unless maybe you need really quiet bedroom levels.

ICBM

Collings said:

I was originally using a jtm45 with a thd powerbsoak but was never really happy and my local tech suggested a ppiv master volume so i gave that a try and it works really well and sounds far better than using a powersoak.

If that was a THD Hotplate it doesn't work well with Marshalls, and especially not the JTM45. The problem with attenuators is that they can be very amp-dependent, depending on their impedance curve usually.

Telejester

Collings said:

I was originally using a jtm45 with a thd powerbsoak but was never really happy and my local tech suggested a ppiv master volume so i gave that a try and it works really well and sounds far better than using a powersoak. I can,t imagine power scaling being much better unless maybe you need really quiet bedroom levels.

Thing is with grouchy neighbours and guitar hating wife, home practice is going to be bedroom volume, so which method curtails jtm45 best and yields best tube tone results ?

Telejester

ICBM said:

Collings said:

I was originally using a jtm45 with a thd powerbsoak but was never really happy and my local tech suggested a ppiv master volume so i gave that a try and it works really well and sounds far better than using a powersoak.

If that was a THD Hotplate it doesn't work well with Marshalls, and especially not the JTM45. The problem with attenuators is that they can be very amp-dependent, depending on their impedance curve usually.

I owned a thd attenuator when i owned a mk1 5150 head and thought they were poor.

Jimbro66

ICBM said:

........The problem with attenuators is that they can be very amp-dependent, depending on their impedance curve usually.

That could be why I never found one I liked, not to mention the potential for output stage damage using some of the very early power soaks.

That's why I went for Power Scaling in my 65 DRRI some years ago. It works OK for me but it is the two-control version. I'm not sure a single control would be so satisfactory.

Would I put it in another amp? Probably not. I'd look hard for a good attenuator that suited the amp simply because there is then no modification to the amp's circuitry or the need to squeeze in two extra controls. Plus an attenuator could be sold separately from the amp if necessary. I doubt that having Power Scaling would add any value to my amp if/when I come to sell it.

timmysoft

The problem that I have with attenuation of any sort is that although your amp is working harder, your ears aren't hearing the same as they would at those big volumes. Unfortunately there's nothing that similulates that effect accurately.

Sporky

Also your trousers don't flap.

RiftAmps

timmysoft said:

The problem that I have with attenuation of any sort is that although your amp is working harder, your ears aren't hearing the same as they would at those big volumes. Unfortunately there's nothing that similulates that effect accurately.

Wisdom awarded 

ICBM

Telejester said:

I owned a thd attenuator when i owned a mk1 5150 head and thought they were poor.

Useful to know - that isn't a combination I've ever tried, in fact I've never tried any attenuator with a 5150. The THD does work well with Fender BF/SF-type and Mesa amps, which prefer a low mismatch - not so well, or badly, with amps that like a high mismatch or a resistive load.

Overall I've found the best results with a combination of master volumes and attenuators though - any attenuator tends to work least well when it's used to bring a cranked amp down to bedroom volume.

professorben

Surely you are better off with a small modelling amp simulating the tone of a wound up valve monster, than shackling a big valve amp to a MV mod or Attenuators? 

If the volumes we are talking about are really are 'bedroom' it's going to naff anyway as the speaker isn't contributing much. 

Jimbro66

When I had Power Scaling fitted to my amp it wasn't really with home practice levels in mind. As others have said, nothing gets close to the sound of a full-on amp when reduced to bedroom level.

In my case I liked the sound of the amp with volume set at around seven but that was too loud for smaller venues (and unpopular with sound men) so Power Scaling allowed me to keep the amp volume control fixed and its output level variable. It works ok in that situation as I'm sure most attenuators would.

hywelg

All methods of reducing output work reasonably well if you don't attempt to do it drastically with any one.

I've got a Hotplate and had a DrZ Airbrake, I have Powerscaling in a 1987 and a Dc30 clone. I also have cabs that go from 95dB (4x10 P10R's) to 102dB. The Hotplate works great with Fender type amps, not with EL84's and not terribly well with the Marshall clone. It does however work fine when I stick 6v6's or EL34's in my D clone. But only down to -8dB. 

Powerscaling similarly, bedroom level isn't good but to knock a bit of volume off its great.

The low efficiency speaker route is great provided you like the tone of the limited choices available. 

Kalimna

Could you recommend any low-efficiency 12" speakers then? Something I am looking for at the moment.

Cheers,

Adam

hywelg

Kalimna said:

Could you recommend any low-efficiency 12" speakers then? Something I am looking for at the moment.

Cheers,

Adam

No sorry, I've only ever tried the Jensen 10's. I keep thinking I'd like to replace them with Emi Ragin Cajuns but then I remember why I'm keeping them!! 

John_A

Telejester said:

Collings said:

I was originally using a jtm45 with a thd powerbsoak but was never really happy and my local tech suggested a ppiv master volume so i gave that a try and it works really well and sounds far better than using a powersoak. I can,t imagine power scaling being much better unless maybe you need really quiet bedroom levels.

Thing is with grouchy neighbours and guitar hating wife, home practice is going to be bedroom volume, so which method curtails jtm45 best and yields best tube tone results ?

With grouchy neighbours and a guitar hating wife a better option would be a modelling am or a new house/divorce (or at least a good talking too)  or even a sound proof practice booth.  I'm sure my Mrs doesn't love it when I play for hours on end at less than sociably acceptable levels, but she knows I'm happy