Passive attenuator for JCM2000 DSL

[PelliX]

Here is a shot of my Weber. That is somehow reactive with the speaker coil.

Nice Weber!

Yup, the speaker coil (or voice coil typically found in many reactive attenuators) emulates the inductance of a real speaker. That means that there can be "interplay" let's call it between the output stage and the load. I'm bad at analogies, but you'll get more interesting games from two guys playing tennis against each other than one guy playing against a brick wall, where the brick wall represents a static, purely resistive load. If that makes any sense...

 

[Doomguy]

That's a purely resistive load box with an L-PAD. Basically, the same as the Bugera PS1 (and many others) just without the line out frills. I sure as heck hope this isn't what they're charging near to 500 euros for....!

I had already seen this image before i decided to pull the trigger.. cause of these reasons:


1. I can't find a bad review about it... many people (in this foum also) claim it's the best passive they tried. Who cares what's in it?
2. Then all passive attenuators shouldn't cost more than the bugera does
3. If the 2 is not true, maybe materials and what the resistors in it are not created equal. As a member of the forum which wrote: ''Resistive attenuators are more tonally complex than everyone thinks. The transformer in your amp provides 70% of the reactive response and using a resistive attenuator tightens that up but doesn't kill it dead. But not every resistor is created equal. Just think how much difference there is between one cable and another? But they're just a bit of copper right? Same thing with resistors! Their construction, the temperature they run at, the materials used to make them, these things all have an audible effect.'' credit goes to the member @Rachael

 

[PelliX]

1. I can't find a bad review about it... many people (in this foum also) claim it's the best passive they tried. Who cares what's in it?

Yup, though there's two sides to that, one of which you touch on later. Sure, you like, why should you not buy it - obviously. However, if you consider that they're asking more than the others constructing the same gear or better... And reviews are all fine and dandy, sure - some things are also very subjective and/or hard to express in numbers. Schematics don't lie (generally ) though. As an engineer I don't believe in "magic", if you see what I mean.

2. Then all passive attenuators shouldn't cost more than the bugera does

Well, there are passive attenuators ranging form mere resistive loads to reactive loads with impedance switching, various outputs, active cooling (powered by the amps' signal), tone control circuits, you name it. That's a pretty big range, and also the reason you pay more for a Weber than a PS1, for example. I do agree that a lot of gear is overpriced, but that's not just attenuators, hehe.

3. If the 2 is not true, maybe materials and what the resistors in it are not created equal.

I have a PS1 and the resistors... well, cheap. The board seemed quite decent, though. But the total cost includes the rest, too, and the resistors aren't the expensive part, really. L-Pads, chassis, transformers for an XLR out or whatnot, that all adds up.

Just think how much difference there is between one cable and another?

*raises eyebrow*

But they're just a bit of copper right? Same thing with resistors! Their construction, the temperature they run at, the materials used to make them, these things all have an audible effect.

I read his statement, and was not really impressed by the lack of any citation of anything containing sources or numbers. I'm not saying he *doesn't* have a point somewhere, though experience tells me it's highly unlikely. Simply stating there's massive differences between "cables" is like stating that many cars are vastly different. It's too broad to bear any meaning or weight.

 

[Resident 217]

I went with the Bugera for my 6101 even thoughI didnt need one with that amp I wanted to see thge difference. The PS-1 has a balanced emulated XLR line out and a regular line out.
The 100 watts is fine for 100 watt amp because when gone through to the amps speaker it adds up to 200watts.

 

[JohnH]

I went with the Bugera for my 6101 even thoughI didnt need one with that amp I wanted to see thge difference. The PS-1 has a balanced emulated XLR line out and a regular line out.
The 100 watts is fine for 100 watt amp because when gone through to the amps speaker it adds up to 200watts.

Better watch out! If you put 100 watts into an attenuator, and maybe its set at say -10db which is 10W output and so still very loud with that 100W amp, then 90W is being taken by the attenuator no matter what your speaker is rated for. And a 100W amp can put out 50% more than that if you decide to crank it.

I would never trust a commercial attenuator rated at 100W with anything more than a 50W amp unless it was being kept at lower settings, and that especially applies to anything made by a company starting with the letter 'B'. Weber is honest about this and will advise a 200W unit for a 100W amp

SPL Reducer

hi @Doomguy , I hope it meets your needs. But is very simple old resistive tech and there is nothing about it that would lead to it sounding particularly great compared to other L-pad designs which these days are much cheaper. But at least it should be well made and hopefully reliable!.

 

[Doomguy]

I have a PS1 and the resistors... well, cheap.

Maybe that explains the difference in the price... I was talking about simple passive attenuators with no extra features (the Bugera and the Harley Benton ones are recommended just for the attenuator and not for these features anyway) like Hotplate, Dr Z air brake, Magus Ultimate Attenuator... same simple philosophy as the SPL, old technology but they aren't that cheaper than the SPL. I know what you mean it looks overpriced but so are other ones in this category.

Yup, though there's two sides to that, one of which you touch on later. Sure, you like, why should you not buy it - obviously. However, if you consider that they're asking more than the others constructing the same gear or better... And reviews are all fine and dandy, sure - some things are also very subjective and/or hard to express in numbers. Schematics don't lie (generally ) though. As an engineer I don't believe in "magic", if you see what I mean.



Well, there are passive attenuators ranging form mere resistive loads to reactive loads with impedance switching, various outputs, active cooling (powered by the amps' signal), tone control circuits, you name it. That's a pretty big range, and also the reason you pay more for a Weber than a PS1, for example. I do agree that a lot of gear is overpriced, but that's not just attenuators, hehe.



I have a PS1 and the resistors... well, cheap. The board seemed quite decent, though. But the total cost includes the rest, too, and the resistors aren't the expensive part, really. L-Pads, chassis, transformers for an XLR out or whatnot, that all adds up.



*raises eyebrow*



I read his statement, and was not really impressed by the lack of any citation of anything containing sources or numbers. I'm not saying he *doesn't* have a point somewhere, though experience tells me i

SPL Reducer

hi @Doomguy , I hope it meets your needs. But is very simple old resistive tech and there is nothing about it that would lead to it sounding particularly great compared to other L-pad designs which these days are much cheaper. But at least it should be well made and hopefully reliable!.

Thank you! I will post here to share my honest thoughts when it arrives

 

[PelliX]

Maybe that explains the difference in the price...

Nah, the resistors are really not going to make a big difference in price, honestly.

like Hotplate, Dr Z air brake, Magus Ultimate Attenuator... same simple philosophy as the SPL, old technology but they aren't that cheaper than the SPL. I know what you mean it looks overpriced but so are other ones in this category.

Agree, there *are* a lot of overpriced ones out there, to be honest...

 

[Resident 217]

Better watch out! If you put 100 watts into an attenuator, and maybe its set at say -10db which is 10W output and so still very loud with that 100W amp, then 90W is being taken by the attenuator no matter what your speaker is rated for. And a 100W amp can put out 50% more than that if you decide to crank it.

I would never trust a commercial attenuator rated at 100W with anything more than a 50W amp unless it was being kept at lower settings, and that especially applies to anything made by a company starting with the letter 'B'. Weber is honest about this and will advise a 200W unit for a 100W amp

SPL Reducer

hi @Doomguy , I hope it meets your needs. But is very simple old resistive tech and there is nothing about it that would lead to it sounding particularly great compared to other L-pad designs which these days are much cheaper. But at least it should be well made and hopefully reliable!.

Thanks for the concern.
Im pretty careful living in an apartment with that much power. Most 100 watt amps are used with double or better rated speaker set ups.
The amps speaker is a 200watt EV12L for the 6101 Marshall so really there is plenty room. to play that thing at full output would be quite fun but, no, I dont think that would ever be likely by me or anyone else as it is crazy loud.

 

[Resident 217]

Nah, the resistors are really not going to make a big difference in price, honestly.



Agree, there *are* a lot of overpriced ones out there, to be honest...

Well at least the SPL reducer looks to have heat sink aluminum resistors, the PS 1 are the block ceramic/sand style similar to those in the Marshalls and Fender amps sometimes on the power tubes.
I recently upgraded to the Two Note Capture 8- it wasn't cheap nor is it cheaply made
I find it an upgrade for me as the emulated line out sounds better than the PS 1 it too is rated for 100w. It does not get as hot as the old Bugara one did.

 

[guitarbilly74]

I've owned pretty much every attenuator mentioned in this thread. None of them is 100% transparent, but they all do the job fine.

But I have to warn against the Bugera because I used it on a show with my 1987x and it overheated and stopped working mid show. And the 1987x is only 50w and was not cranked.
Although, to its defense, I tested it the next day and it was working again lol so it just needed to cool off. But obviously that didn't help me during the show.

The TAE is great but it's a whole different animal, since it's a re-amp device with a load and a dedicated power amp and they're quite expensive. In the same style, the Fryette Power Station is also great and IMHO superior to the TAE since it's an actual tube power section. . But these are pretty much like buying another amp since they're pricey and you are actually introducing another power amp to the equation.


For straight up passive attenuators, the best attenuator I've used with Marshalls is the good ol' THD Hot Plate. It retains the tone really well until -8db and even -12db with the switches on. They were voiced to be used with Marshalls and work really well. Also, contrary to popular belief, the Hot Plate is a fully reactive attenuator. I still prefer it over any of the newer attenuators I've tried and it's the only one that I kept. Seems like they got it right the first time around. Also, every time I've seen a passive attenuator in a pro stage, it was the THD. They're sort of an industry standard.

 

[PelliX]

Well at least the SPL reducer looks to have heat sink aluminum resistors, the PS 1 are the block ceramic/sand style similar to those in the Marshalls and Fender amps sometimes on the power tubes.

Correct, and they are cheaper of course because of the omission of the heatsink. They only make sense in constructions where they can further dissipate their heat (like in the SPL design, they use the chassis). Typically the cathode resistors and such in Marshalls and Fenders are mounted on a board or on the sockets and are not touching the chassis. I agree, it would often be better to do so, but also marginally more expensive.

I find it an upgrade for me as the emulated line out sounds better than the PS 1

No joke, haha! I'm sure it does!

it too is rated for 100w. It does not get as hot as the old Bugara one did.

Well rated for 100W is a bit of "misguided spec", often. What some do (like the PS1, IIRC) is use the max values of the components involved. If that equates to 100W of dissipation - they call it a 100W attenuator. While that's not untrue, we all know a 100W high gain amp will easily push 150W or more at peak, so the attenuator is insufficient. Some take this factor into the equation and produce a "150W max dissipation unit", then label it "for use with 100W amps". Again, not untrue, then there's tolerance and headroom. Generally, when you design a circuit, you don't want components like resistors operating at 100% as it decreases their lifespan, increases the risk of failure and provides no safety margin. A factor of two is not uncommon. So then you might find a unit (I believe Weber generally does this) that's spec'd for maybe 200W+ of maximum dissipation and they state it will handle a 100W amp. After all, you might be able to drive 30 in first gear, but we all agree it's not doing your engine a favor.

Fact of the matter is, the SPL may work just fine, it also looks decently constructed. However, it remains a purely resistive load. Whether that flips your switch with exactly your amp and your cab - only you can answer. The fact they charge over 400 for it is just insane, though. 6 resistors, an L-Pad, switches, jacks and a project case. It just doesn't add up. Plus - and I'm really not trying to knock it here - on the pics I found online they have wires' insulation touching the heatstinks. If that insulation melts and the heatsink (and thus the chassis) is energized you could be in hell's kitchen, depending on the setup.

 

[Burk]

H

Hi everyone!

I am thinking about getting an attenuator for my 2000 DSL 100.

I play this head at a local club with a proper stage during the summer and really enjoy it.

However now that i brought it back home I can't turn the ultra channel volume beyond 3.. and i am worrying that my 1936 cabinet that is soon to arrive will make things worse

There is a disturbing fizzy high frequency when I play the amp's red channel below volume 3 that disappears when I turn the amp louder.

Any guys who happen to use attenuator on this model and are happy with it?

Disclaimers:

1. The jcm2000 dsl head doesn't have a "master volume" unlike the Vietnamese new DSL100HR that has two more knobs that do exactly that...
2. I want a passive one cause i am not interested in recording, IRs and stuff like that.. just for playing my amp at home at lower volume. Not TV volume necessarily... I can play loud at home but not that loud. Also interested in using it at the gig to see if i can get an even warmer tone.
3. I managed to tame that annoying frequency with an EQ pedal, but I still wanna try attenuating the amp...
4. Passive attenuator recommendations are welcome, but i am from Europe. Was looking at some German made ones like the SPL silencer

Any thoughts? Hand on heart, are you satisfied with attenuating your DSL?

Thank you!

Have you tried pulling the two inner or two outer power tubes out ? Just curious…..

 

[gbirocco]

Hi everyone!

I am thinking about getting an attenuator for my 2000 DSL 100.

I play this head at a local club with a proper stage during the summer and really enjoy it.

However now that i brought it back home I can't turn the ultra channel volume beyond 3.. and i am worrying that my 1936 cabinet that is soon to arrive will make things worse

There is a disturbing fizzy high frequency when I play the amp's red channel below volume 3 that disappears when I turn the amp louder.

Any guys who happen to use attenuator on this model and are happy with it?

Disclaimers:

1. The jcm2000 dsl head doesn't have a "master volume" unlike the Vietnamese new DSL100HR that has two more knobs that do exactly that...
2. I want a passive one cause i am not interested in recording, IRs and stuff like that.. just for playing my amp at home at lower volume. Not TV volume necessarily... I can play loud at home but not that loud. Also interested in using it at the gig to see if i can get an even warmer tone.
3. I managed to tame that annoying frequency with an EQ pedal, but I still wanna try attenuating the amp...
4. Passive attenuator recommendations are welcome, but i am from Europe. Was looking at some German made ones like the SPL silencer

Any thoughts? Hand on heart, are you satisfied with attenuating your DSL?

Thank you!

Hi everyone!

I am thinking about getting an attenuator for my 2000 DSL 100.

I play this head at a local club with a proper stage during the summer and really enjoy it.

However now that i brought it back home I can't turn the ultra channel volume beyond 3.. and i am worrying that my 1936 cabinet that is soon to arrive will make things worse

There is a disturbing fizzy high frequency when I play the amp's red channel below volume 3 that disappears when I turn the amp louder.

Any guys who happen to use attenuator on this model and are happy with it?

Disclaimers:

1. The jcm2000 dsl head doesn't have a "master volume" unlike the Vietnamese new DSL100HR that has two more knobs that do exactly that...
2. I want a passive one cause i am not interested in recording, IRs and stuff like that.. just for playing my amp at home at lower volume. Not TV volume necessarily... I can play loud at home but not that loud. Also interested in using it at the gig to see if i can get an even warmer tone.
3. I managed to tame that annoying frequency with an EQ pedal, but I still wanna try attenuating the amp...
4. Passive attenuator recommendations are welcome, but i am from Europe. Was looking at some German made ones like the SPL silencer

Any thoughts? Hand on heart, are you satisfied with attenuating your DSL?

Thank you!

Hello! I am an italian happy owner of SPL Reducer; with this I can study at home by setting my SV20H all the way up (loudness at 10 with 5W power). Obviously I can't expect to hear the sound of a Plexi 100W all the way up at Madison Square Garden stage (also for a lot of other reasons … ) but for study scope, with a decent sound, without disturbing the neighbors, it's fine. Even at rehearsals with the band it allows me to play, with satisfaction, everything at 10 with 20W power, with a credible sound.
P.s. I play in a Led Zeppelin tribute band

 

[Doomguy]

Fact of the matter is, the SPL may work just fine, it also looks decently constructed. However, it remains a purely resistive load. Whether that flips your switch with exactly your amp and your cab - only you can answer. The fact they charge over 400 for it is just insane, though. 6 resistors, an L-Pad, switches, jacks and a project case. It just doesn't add up. Plus - and I'm really not trying to knock it here - on the pics I found online they have wires' insulation touching the heatstinks. If that insulation melts and the heatsink (and thus the chassis) is energized you could be in hell's kitchen, depending on the setup.

I agree with all this, I bought it used for 300 which some may still consider a lot for a purely resistive load. It's gonna be here on Monday. I had these choices:

- buy the SPL used for 300 from somewhere nearby (arriving on Monday)
- buy a new one from Thomann, like a Palmer one for 250
- experiment with a cheap one, like a Bugera or a Harley Benton one from Thomann, plus 20 for shipping (as I mentioned, I have already made on order from Thomann waiting for my 1936 cab to arrive along with other stuff, mics, cables etc so there is nothing else I need to buy at the moment to exceed the ''free shipping'' cost)
- buy a used one from Reverb (THD Hotplate, Weber, Ultimate Attenuator, Dr Z brake etc etc) for more or less the same money as the used SPL reducer

I went with the 1st option. From the 2nd or 3rd option I would save around 50 -150ish euros, so I thought what the heck, let's go with the SPL.

I will share my honest opinions on Monday. I have my expectations low, right now I can't tell if I would buy an SPL for brand new at the price they are asking for, but I will on Monday...

Have you tried pulling the two inner or two outer power tubes out ? Just curious…..

No I haven't... I've read about it but I don't know... even if it is it 100% safe for the amp I am reluctant to try it... except if I was in the middle of a gig and one of the power tubes blew out and I had to keep playing

 

[PelliX]

- buy a new one from Thomann, like a Palmer one for 250

Yeah, that's another funny example. I know the Palmer PDI-03's were used extensively by pro's (Status Quo, Brian May and I've heard a lot of others cited to have used them). They're just a resistive load box with very elementary speaker emulation. Of course, when they were being used, there weren't as many options out there as there are now, but still curious.

- buy a used one from Reverb (THD Hotplate, Weber, Ultimate Attenuator, Dr Z brake etc etc) for more or less the same money as the used SPL reducer

My money would have been on the Weber, but as long as you're happy, it's all good!

No I haven't... I've read about it but I don't know... even if it is it 100% safe for the amp I am reluctant to try it... except if I was in the middle of a gig and one of the power tubes blew out and I had to keep playing

There are only really a handful of amps that are unable to aptly handle this. You would have to measure the B+ with two output valves missing and check the ratings on the components to see if that amp is affected. I honestly doubt it, as I don't believe they ran at *very* high voltages, but I'm not sure of the levels off the top of my head.

 

[LyseFar]

H

Have you tried pulling the two inner or two outer power tubes out ? Just curious…..

It makes actually no big difference in volume - 3db, barely audible. I would go with the attenuator.

 

[LyseFar]

This thread inspired me to do a soundcheck with my favorite attenuator. “The Depthcharge”.


With this Mexican strat (pickups changed to Texas Specials).


The settings:

And the two channels are jumpered.

And the noodling recorded with an SE Electronics X1R.



Sorry about the playing - I am foolin around with the guitar volume and pickups… The idea is to demonstrate that a Super Lead can be tamed and still maintain the clarity with an attenuator.

 

[PelliX]

This thread inspired me to do a soundcheck with my favorite attenuator. “The Depthcharge”.

Wow, that's a cool design!

Any pics of the insides? I presume you built that yourself?

 

[Doomguy]

Yeah, that's another funny example. I know the Palmer PDI-03's were used extensively by pro's (Status Quo, Brian May and I've heard a lot of others cited to have used them). They're just a resistive load box with very elementary speaker emulation. Of course, when they were being used, there weren't as many options out there as there are now, but still curious.

the Palmer didn't get my vote cause it only has 5 levels of attenuation (which could work for me though and I don't think the amp will sound good at minus infinite, but why not have that feature?) but mostly becasue it only comes with one ohm impedance option... and costs brand new 275 (the 8 ohn one) so I decided that for 25 more the -used- SPL is worth it

@LyseFar thank you for sharing!! That is a CRACKING tone

 

[LyseFar]

Wow, that's a cool design!

Any pics of the insides? I presume you built that yourself?

No I did not build it myself. But my tech was involved with the design that is very simple. Unfortunately no photos.
Two circuits in parallel - one side with two 8ohm automobile speaker units in serial and the other circuit one 8 ohm speaker and a 8ohm L-pad in serial.
So when max attenuaton it shows the amp 8 ohm and with min attenuation you get 6db attenuation and 6. something ohms load on the amp.
But as it is just speakers and damping material it is very responsive and has a very great feel.