Power Attenuators Vs. Variacs

[nonamemx]

I understand that Eddie Van Halen used a Variac to lower the voltage of the amp, letting him crank it at lower volumes.

Is this a good alternative to a Power Attenuator, such as the THD Hotplate and the Marshall Powerbrake.

Is it safe? effective?

I froogled and came up with this, would this work like I want it to?
http://www.davesbargainoutlet.com/Vi...=PowerstatL10C

Thanks!

[Twisteramps]

Re: Power Attenuators Vs. Variacs

variac is a bad idea... it lowers ALL the voltages in your amp. It throws off the bias of the tube, and also can affect the heater voltages in a bad way if you cut too much power. It's not going to really make that much of a difference as say a hot plate will, but there is no such thing as a perfect attenuator. All of them affect the tone in some way. For recording, you're better off with an iso box.

Pete

[nonamemx]

Re: Power Attenuators Vs. Variacs

damn!

I was hoping that that was an easy budget way to crank at low volumes! Then how did EVH get away with it?

As you can obviously tell, Im not educated much on power attenuators.

3 new questions (not necessarily directed for Twisteramps):

1. A power attenuator goes in between the amp and the speaker, correct?

2. will a power attenuator let me have the amp cranked at comfortably quiet volumes? Like, bedroom volumes for when Im not rehearsing or gigging?

3. My budget is tight, what would be the best bet as far as value goes? Marshall Powerbrake or THD Hotplate? (or other)

Thanks.

[Fragle]

Re: Power Attenuators Vs. Variacs

[ QUOTE ]


I was hoping that that was an easy budget way to crank at low volumes! Then how did EVH get away with it?

[/ QUOTE ]

he had enough money to replace the tubes after every show, as well as the transformers and other damaged things once it is neccessary.

[ QUOTE ]

1. A power attenuator goes in between the amp and the speaker, correct?

[/ QUOTE ]

correct. your speaker cable goes from the speaker outs on your amp into the attenuator and from there into your cabs

[ QUOTE ]
2. will a power attenuator let me have the amp cranked at comfortably quiet volumes? Like, bedroom volumes for when Im not rehearsing or gigging?

[/ QUOTE ]

no. it is definitely impossible to crank you amp to 10 and all you hear is bedroom whistle. your sound will still be pretty loud, just not ear-splitting loud.
but for example, if you can only turn your amp up to 0.5 on the master volume for bedroom use, you might be able to turn it up to like 2-3 when using an attenuator.

[ QUOTE ]
3. My budget is tight, what would be the best bet as far as value goes? Marshall Powerbrake or THD Hotplate? (or other)


[/ QUOTE ]
no idea, sorry [img]/images/graemlins/wink.gif[/img]

greets
fragle

[charvelguy]

Re: Power Attenuators Vs. Variacs

Pete knows what he talking about, as I think I can safely say he has probably quested in earnest for the 1watt tone more than just about anyone here.

IN answer to your questions.
1. yes
2. yes, some even have headphone outs.
3. It depends on what you want and features.
Years ago we used one called an Altair, which was one of the first out on the market and seemed to do an ok job. I never had any problems using one or had any issuess with my amp using one either as far as I know.
I thought power soaks were ok, but their reliability was horrible-I have a whole box of them in various stages of needing to be fixed. If it wasn't the board, it was the resistors.
Soo...I think Powerbrakes or a THD are a good value used and probably your best bet. I use an SE100, similar to a powerbrake...but they're rather pricey now. THere are a few other brands out there, maybe someone else with far more money invested in this than myself can shed more light on the subject.

[lerxstcat]

Re: Power Attenuators Vs. Variacs

I actually still have my Altair PW-5! And contrary to the above statement, I could crank
my amp and get a bedroom volume if I used max attenuation. Of course it takes a lot of high end out of your tone though. I always heard that Altairs could fry Marshall heads though, but I used mine with a Traynor YBA-1A head, which is pretty hard to harm, so I may have been lucky with that combo. They also say the connections in the Altair would overheat and come unsoldered, causing your volume to suddenly jump to full output. I never experienced that either, but it's said often enough that I should mention it. But the PW-5
ad an Electro-Harmonix LPB-2 were my gain and master volume solution in the old days, using actually 2 LPB-2s for clean (no LPB-2), crunch (1 LPB-2) and lead drive (2 LPB-2s).

I would say the THD Hotplate is the better choice over the Power Brake, not that I am an expert but from reading other threads here in the past that is what those who ARE more expert than I have said.

[charvelguy]

Re: Power Attenuators Vs. Variacs

I've heard that about the Altair too..but I had pretty good luck with mine running a 50 watt JMP.

I was always leary using any kind of power attenuator with my amps and I have fried my Marshalls a time or two with a power soak. Nothing like green smoke from a fried output transformer coming out of the back of your amp while the volume diminishes.


I have not heard of any problems with powerbbrakes, but when you are trying to damp a 100watt-200watt amp load, man that has to put some stress on and heat up the attenuator.
I personally would stear clear of a Scholz powersoak and if you do use any of these things, put a small AC fan in it or by it and you should strongly consider one for your amp as well if it doesn't come equiped with one.

[nonamemx]

Re: Power Attenuators Vs. Variacs

Alright then. I feel very educated now [img]/images/graemlins/smile.gif[/img]

Thanks Fragle, Charvelguy, lerxstcat *nods*

I was probably going to look at the THD first, since its $100 cheaper than the Powerbrake.

Thanks for the usage tips too!

[atilla]

Re: Power Attenuators Vs. Variacs

Why not look into a 1/4 watt amp from Songworks?

[nonamemx]

Re: Power Attenuators Vs. Variacs

I just checked out songworks. . its not really what Im looking for.

Thanks anyway guys.

I plan to get a Marshall JCM 800 combo. Will it have the same crunch as a halfstack, I noticed that they have open back constuction, how will this effect the sound?

[charvelguy]

Re: Power Attenuators Vs. Variacs

The open back combos have a different sound, but they're not bad, maybe a little 'weak' compared to a closed back 4x12. The amp itself basically a head with an open back cab.. you could put it up closer to being against a wall if you worry about fullness.
I used one for a couple months and I'm pretty sure you can run them like a straight head into your cab of choice as well. I personally found them to be a little lacking in the gain end (for me) unless it was driven by a external box of choice or pushed very loud.
Be prepared to bust a nut tho.. those things are mucho heavy tanks.

I know you have your heart & mind set on a JCM, so I don't want to end up sticking my nose into your biz and possibly later my foot in my mouth to much here as they can be a great amp for the right person. (Marshalls do tend to vary from amp to amp at times) But again, really consider checking around and trying a few other variables if you are looking at spending that much and are concerned about bedroom volume/attenuation and practice volumes. Mesa & THD make some great lower wattage amps that can get close to the Marshall and beyond as far as flexibiity.

[jgcable]

Re: Power Attenuators Vs. Variacs

A Variac works great providing you can repair your amps on a regular basis. EVH's amps were repaired constantly.

[nix]

Re: Power Attenuators Vs. Variacs

I have a Hotplate I use on a Fender Prosonic I use as a practice amp. The amps tone is terrible right now b/c it needs new tubes. Everything is original since new in 1996! So...I have no basis of judging tone on the THD but it lets you crank the amp up all the way if you want and give you total control of the actual volume. On the Prosonic, I keep the clean channel vol on 10 to get a nice crunch and adjust the level with the HotPlate.

[nix]

Re: Power Attenuators Vs. Variacs

Oh, by the way, the THD seems to be a pretty decent quality product. Mine is approx 4 years old. Bought it used for like $125. If you use it on an practice/bedroom amp that stays where it is all the time it is pretty much a set and forget product once you figure out what settings you like. I use mine strictly as a volume knob and i never touch the amp vol anymore. Thought that info might help.

[nonamemx]

Re: Power Attenuators Vs. Variacs

OH GOOD GOD!

I headed up to GC today, and headed for the used section just to see what they had.

By pure luck, they had a JCM 800 combo! I CANT BELIEVE THE TONE, its what I have been searching for at least a year and I have wasted so much time poking around at all the wrong amps.

JCM 800 combo is my next amp for sure. I dunno about this one. Its a 50watt, 1x12 single channel. It says "Hot Rodded" Im not sure what all was done to it, but it sounds great. Perhaps some effects loop work or some bias adjustment, there were 2 added knobs on the back of it, that dont say anything.

They want $875 for it, and thats the Post-hagglement price.
Fair price? I dont really want to ebay one.