Can anyone explain the different types of attenuators to me?

[Matt300ZXT]

I've seen the THD Hotplate for years, Marshall Powerbrake, etc and I've always heard they work fine but shorten power tube life or put extra strain on the amp, something along those lines. Now I've been seeing all these newer models referred to as reactive, or something along those lines, that are supposed to be a much better design for tube amps.

All I know is I'm tired of not being able to crank my Budda Superdrive 45 and other amps without pissing off the people 2 miles down the road.

 

[paulyc]

I don't think any attenuator is an ideal solution, you can only take a few db off before tone loss and shitty sound occurs. I have the Marshall Power Brake and the THD Hot Plate, I've used the Scholz and Altair ones back in the day. None are great. Maybe the Suhr or Rivera ones are better, IDK.

 

[lockingtuner]

I've seen the THD Hotplate for years, Marshall Powerbrake, etc and I've always heard they work fine but shorten power tube life or put extra strain on the amp, something along those lines. Now I've been seeing all these newer models referred to as reactive, or something along those lines, that are supposed to be a much better design for tube amps.

All I know is I'm tired of not being able to crank my Budda Superdrive 45 and other amps without pissing off the people 2 miles down the road.

I have experience with the Two Notes Reload, the Captor, and the Fryette Power Station 2. For me, the Fryette has been great.

 

[lockingtuner]

I've seen the THD Hotplate for years, Marshall Powerbrake, etc and I've always heard they work fine but shorten power tube life or put extra strain on the amp, something along those lines. Now I've been seeing all these newer models referred to as reactive, or something along those lines, that are supposed to be a much better design for tube amps.

All I know is I'm tired of not being able to crank my Budda Superdrive 45 and other amps without pissing off the people 2 miles down the road.

I realize I didn't answer the question in the subject line. I suggest reading the manual for the Two Notes Reload here: https://www.two-notes.com/en/torpedo-reload. Then I'd suggest reading the Fryette PS2 manual here: http://fryette.com/power-station-integrated-reactance-amplifier/

It may seem like a lot, but once you figure out the basics, you'll have more questions, and these will have already answered them. Between the two, the feature sets are different enough, you could go either way.

 

[stephen sawall]

Running the amp hot wears out tubes faster. It does not matter if you are using a attenuator or speakers.

I don't crank my amps when using attenuators. I just turn it up to the sweet spot and control the volume with the attenuator. Often I need to fine tune the amp once I get the volume I want. Usually means turning up the low and highs.

There is two basic types of attention usually used. Most use capacitors to load down the amp and EQ the sound to make it sound balanced.

The other type completely loads the amp and uses a other amp to get the volume where you want it.

The first type if it has a line out can be used like the second type with a other amp.

Just take the line out of the attenuator and run it into the effects return of a other amp.

I have a Hot Plate and use it both ways.
I would say about half my amps I prefer the sound over just using the Master volume on the amp. Other amps it is just not needed.

 

[stratjacket]

There are basically 2 types:
Resistive - These are the old school ones (Hotplate, powersoak, etc..). They simply act as a resistive load to the power amp so the amp sees an 8 ohm load for example. As noted, these do not sound as good, the highs get attenuated and it sounds like something threw a blanket over the cabinet. The main problem here is that a speaker moves and reacts to the power amp, so that there is an interaction between the two. The simple resistive load is constant, so the power amp does not get the same interaction and it sounds worse.

Reactive - These are the fairly new, only a few years old ones. These do NOT use a resistive load, instead they use a type of inductance so it reacts just as a speaker does with the power amp. The Suhr Reactive Load for example was designed to appear as a Celestial Greenback speaker. So The Power amp sees and feels and reacts as if a Celestion greenback speaker is connected. The result is a great sound that allows you to use any of a million IR speaker responses to shape the sound.

Having had many of the old ones over the years I can tell you it is NIGHT and DAY difference. I get better sounds from my Reactive loads running through different Speaker Impulse Responses than anything else.

 

[stephen sawall]

The THD Hot Plate is reactive. Always had been.

 

[stratjacket]

The THD Hot Plate is reactive. Always had been.

Curious where did you get this info?
I've never read where it has the same non-linear resistance as a speaker does and it certainly doesn't sound anything as good as a reactive load. Also there are no claims or reference in any Hotplate documentation saying it is a reactive load.

 

[stratjacket]

The more I think about it, I guess it could be claimed that the hotplate is not purely resistive and does have some EQ compensation. So there is a reactive element there. But I think that is a far stretch from it being reactive in the way a speaker is and interacting with the power amp the same way. The difference in sound is pretty clear that it's not reactive like the newer Two Notes, Suhr RL, Fractal Load, Fryette, etc..

 

[stephen sawall]

The THD Hot Plate is reactive. Always had been.

Curious where did you get this info?
I've never read where it has the same non-linear resistance as a speaker does and it certainly doesn't sound anything as good as a reactive load. Also there are no claims or reference in any Hotplate documentation saying it is a reactive load.

I was told this by Andy Marshall and Ed Degenaro in conversation.
The fan is part of reactive load in the Hot Plate.

 

[fusedbrain]

There are basically 2 types:
Resistive - These are the old school ones (Hotplate, powersoak, etc..). They simply act as a resistive load to the power amp so the amp sees an 8 ohm load for example. As noted, these do not sound as good, the highs get attenuated and it sounds like something threw a blanket over the cabinet. The main problem here is that a speaker moves and reacts to the power amp, so that there is an interaction between the two. The simple resistive load is constant, so the power amp does not get the same interaction and it sounds worse.

Reactive - These are the fairly new, only a few years old ones. These do NOT use a resistive load, instead they use a type of inductance so it reacts just as a speaker does with the power amp. The Suhr Reactive Load for example was designed to appear as a Celestial Greenback speaker. So The Power amp sees and feels and reacts as if a Celestion greenback speaker is connected. The result is a great sound that allows you to use any of a million IR speaker responses to shape the sound.

Having had many of the old ones over the years I can tell you it is NIGHT and DAY difference. I get better sounds from my Reactive loads running through different Speaker Impulse Responses than anything else.

This is good info ( not withstanding whether the Hot plate is resistive or reactive - I beleive it to be resistive, but whatever.... )

Just wanted to add that, in the "reactive" category, there are 2 sub groups. There are units like the Freyette power station that knock the output of the amplifier all the way down to line level, and then re-amp it back up to your desired output level.
Others, like the Rivera Rock Crusher, are reactive loads, but only attenuate the amplifier output level down to your desired level. There is still a line out for IR's, but the attenuated signal to the cab is attenuation only, no re-amping.

Also note that the Suhr Reactive Load is only a load box, and needs to be used with IR's. I believe you can still connect a cab, but there is no attenuation for the cab signal.

If you are only wanting to use IR's to record, the Suhr is a good choice. If you need to attenuate the level of a cab, go with the Freyette unit, or look at the Two Notes stuff.

 

[skoora]

Hell, I've been using a Marshall power brake for almost 15 years and it sounds great. I've used it on 100 watt plexi builds and it sounds good almost all the way down. Last few clicks were where it got noticeably different. I have a 4 Ohm hotplate that I bought for a Fender I used to have but don't use it now I longer have that amp. I like the Power Brake better than the hotplate. I have consistently run my amps through the power Brake for the last 10-15 years and have never had a tube failure or failure of any kind. All my amps are MV amps but sound better, like Stephen said, when you get them in the sweet spot. The difference in all my Boogies between using the Master and using the attenuator with the Master up a fair bit is very noticeable to me. The MKV is a different (to me better) amp at volume. Also my Laney pro tube sounds better if the Master is up to 4 or 5.

 

[Kapo_Polenton]

I have a Torpedo Reload.. sounds good but definitely alters the tone compared to straight in. It is slight but it is def. there.

Had a hotplate, liked it the first few clips back just taking the edge off the volume.

Ultimately, every amp sounds the best with NO attenuator.

 

[stephen sawall]

I asked Ed about the Hot Plate...

"Mostly resistive, reactive only when the deep switch (inductor) is engaged."