Turning off VHX Power Tubes

[Spidouz]

Hi guys, quick introduction of myself since it’s my first message here, I had a rig with a Two-Rock Studio Signature (clean) and Dr Z EMS (Marshall crunch) and now I want to build a complete new rig that will be fully digitally controlled Analog & Tubes. So I sold my Two-Rock (hard to part away with it because I love this amp, but I need the money for the new rig). I hope I will like the VHX clean as much as my Two-Rock…

So yeah, my new rig will be obviously composed of the Diezel VHX and then a small pedalboard in front of the amp (with Sonuus Wahoo and Voluum, the Kernoms (Ridge, Moho, Elipse) and eventually a Feel the Tone PA1QG). So I can keep a whole analog path from the pickups to the Preamp, but I can save the whole signal chain and settings and recall them with MIDI.

My main concern is that I have a 2x12” at home that I love (Dr Z EMS with Creamback and 70th Anniversary G12H30), except it’s only rated for 60w. I know I could change the speaker (that’s my last ressort), but I really love the G12H30 that I already had in my Marshall 2061CX that I had for my Two-Rock. So I wonder if there’s a way to turn 2 of the VHX Power amp off? (to make sure that when I’m on my home cab I won’t fry my speaker even if I play loud. And then quickly turn them on when I go to the studio on a 100w cab).

This is NOT about volume or loudness, I know Diezel amps have a GREAT master volume, it’s all about protecting a 100w from frying a 60w cab. Apparently I could remove two of the power tube, but I would prefer to do it in the Global preferences instead of removing them physically.

PS: I should have the VHX in February or March, Thomann told me they should have in stock by them, and it matches my plan time wise (=$$$) — I just can’t wait, I’ve been lurking on the VHX for the last 2 years, but always got sidetracked by some life stuff. Also, I listed my previous rig and the gear I want to use only to give you an idea to where I come from and what I want to accomplish with the Diezel VHX. I’m not comparing gear, or telling that some speakers are better than others, etc… it’s just what I like, that’s it.

 

[MourningEngine]

You will only have 100W output at max volume. With master low you will likely have between 0.1W and 1W. So there is no issue with your 60W cab. With the master knob you are controlling output power (=wattage).

There is no way to power off power tubes.

 

[Spidouz]

This is NOT about low volume, this is about when I’m playing LOUD with a Drummer when I’m using my home cab that is only 60w, I don’t want to play the “guess game” to how loud I can push it before it’s too late.

 

[MourningEngine]

Understand! In this case there is no definit answer on how high you can run your master volume without measuring the output power at given master volume position and given load (=your cab).

 

[Spidouz]

Yeah, that's what I was afraid of, and that's why I would love a way to disconnect 2 of the 4 Power tube, so even if I dimmed the amp to the maximum, it wouldn't output anything above 45-50w.

Obviously, I'm not gonna play fully dimmed like I would when using a loadbox, there's no point I guess with the VHX since it has a Direct Out and can be used cabless, so I wouldn't use load box and wouldn't be tempted to dimm the amp, but still, it would be great to have this option to switch 2 power amp tubes off. For instance, on Two-Rock 100w amp, you often have a switch to turn it down to 50w, it's not just for the power/volume, but also for that difference in tone you can get with headroom/compression. Not sure how it translates with Diezel since I never play on a Diezel yet, the VHX will be my first...

 

[MourningEngine]

As of now there is no option to deactivate a pair of power tubes on the VHX.

 

[Spidouz]

thanks for the info.

As said, worst case scenario, I can always change my speakers in the cab, but I really love my G12H30 in my 2x12" vertical, if only it would support 50w, it would be perfect, but that's another battle. But I could always use the brutal method, which consists to simply use the VHX with my cab, push it when playing it loud with a drummer, and if it breaks and frys my speakers, then it means it will be time to replace them. Most of the time, I still play at reasonable volume anyway when I'm alone at home...

One sure thing is that it's not a dealbreaker for me, I will get the VHX. It's just some logistics to be ready when it will arrive...

 

[FLUXX]

Spidouz,
Don't worry, you can attenuate the VHX when you are at home by pushing the Preset Manager Knob,
and lower the Master control there by however you need, to lower the output of the amp.
Just remember to put it back to "0" when you play with the band.

You don't lose the tube feel either. It's a great feature.
Have fun with your new VHX!

 

[Spidouz]

Yeah you’re right, just in case I checked to swap the speakers and might change them for a G12-M65 and probably a Vintage 30 to spice things up, so I can still switch the 16 Ohms cab into a 8 Ohms to have only 8 Ohms everywhere, so I can use them later with an amp switcher such the Ampete 442… It’s just not something I wanted to purchase right away, so I will be careful and will the master control until I get everything done.

 

[belensky]

This is NOT about low volume, this is about when I’m playing LOUD with a Drummer when I’m using my home cab that is only 60w, I don’t want to play the “guess game” to how loud I can push it before it’s too late.

Very general and overly safe rule of thumb is that you want to have twice as much wattage in the cabinet as you have in the amp, meaning that if you have a 100 W head, ideally you want a 200 W cab. A typical 4×12 cab loaded with V30s is rated at 240 W.

But it's just theory. In reality, for example, a 60 W Vintage 30 speaker can withstand a lot more. They used to rate them at 70 W, now they rate them at 60 W, but essentially it's the same speaker. The thing is, speaker manufacturers are also playing the safe game here — when they rate a speaker, they intentionally lower the max wattage so if somebody tries to be EVH for a second and cranks a Plexi on 10, the speaker will still handle it. So a so-called 60 W speaker can actually withstand 120 W or even more depending on the type of signal, how long it’s played, and the cabinet type (closed sealed cabinets are easier on speakers under extreme conditions since the back baffle acts as a limiter, pushing the speaker back).

Another thing — playing loud with a drummer. If we’re talking about rehearsals, is it really that loud? I used to rehearse with a Herbert and more often with my 60 W DIY Mesa Rectifier, and that Mesa wasn’t even at 50% on the master, so around 30–40 W at best. No issues for years. If we’re talking about home use, it’s 2–3 W at best, so any speaker will fit.

For what it’s worth, I tried the Herbert into a 2×12 cab with two V30s and set it really loud — around 1–2 o’clock. It’s painfully loud, but the cab handled it just fine. I’d say this kind of volume is more suited for arenas and really big clubs if you want to annoy your bandmates, rather than rehearsal spaces or small clubs.

So really, I wouldn’t be all that concerned. Just don’t go crazy with volume — play just as loud as your drummer, with a slight boost for solos, and keep the Deep settings on the lighter side, and you’ll be fine. There’s absolutely no reason to take out power tubes or mismatch impedance output. You’ll hear the speakers maxing out long before you blow them, so as long as they sound fine, they are fine.


Same thing goes for load boxes. I’ve heard a lot of people worry about plugging a 180 W Diezel Herbert into a 100 W load box. Again, you just want to keep your master volumes at realistic levels — anything between 0 and 12 sounds great, and anything past 1 starts to introduce unnecessary power amp distortion. I’ve played a Suhr RL with a Diezel Herbert for years, and at those volume levels (lets say 10–12), you barely even warm up the load box.

 

[VHTStark]

Very general and overly safe rule of thumb is that you want to have twice as much wattage in the cabinet as you have in the amp, meaning that if you have a 100 W head, ideally you want a 200 W cab. A typical 4×12 cab loaded with V30s is rated at 240 W.

But it's just theory. In reality, for example, a 60 W Vintage 30 speaker can withstand a lot more. They used to rate them at 70 W, now they rate them at 60 W, but essentially it's the same speaker. The thing is, speaker manufacturers are also playing the safe game here — when they rate a speaker, they intentionally lower the max wattage so if somebody tries to be EVH for a second and cranks a Plexi on 10, the speaker will still handle it. So a so-called 60 W speaker can actually withstand 120 W or even more depending on the type of signal, how long it’s played, and the cabinet type (closed sealed cabinets are easier on speakers under extreme conditions since the back baffle acts as a limiter, pushing the speaker back).

Another thing — playing loud with a drummer. If we’re talking about rehearsals, is it really that loud? I used to rehearse with a Herbert and more often with my 60 W DIY Mesa Rectifier, and that Mesa wasn’t even at 50% on the master, so around 30–40 W at best. No issues for years. If we’re talking about home use, it’s 2–3 W at best, so any speaker will fit.

For what it’s worth, I tried the Herbert into a 2×12 cab with two V30s and set it really loud — around 1–2 o’clock. It’s painfully loud, but the cab handled it just fine. I’d say this kind of volume is more suited for arenas and really big clubs if you want to annoy your bandmates, rather than rehearsal spaces or small clubs.

So really, I wouldn’t be all that concerned. Just don’t go crazy with volume — play just as loud as your drummer, with a slight boost for solos, and keep the Deep settings on the lighter side, and you’ll be fine. There’s absolutely no reason to take out power tubes or mismatch impedance output. You’ll hear the speakers maxing out long before you blow them, so as long as they sound fine, they are fine.


Same thing goes for load boxes. I’ve heard a lot of people worry about plugging a 180 W Diezel Herbert into a 100 W load box. Again, you just want to keep your master volumes at realistic levels — anything between 0 and 12 sounds great, and anything past 1 starts to introduce unnecessary power amp distortion. I’ve played a Suhr RL with a Diezel Herbert for years, and at those volume levels (lets say 10–12), you barely even warm up the load box.

Beat me to it, but you are 100% right! When I bought my Herbert mk3, I initially wanted the Diezel FL 4x12 to pair with it. I ended up the V30 2x12 as a stop-gap....but was super worried about using it with the Herbert's 180+ watts!

Anyway, Peter Stapfer told me himself the 2x12 could handle the Herbert no problem....unless I was planning on running the Herbie dimed all the time, which I wasn't going to do anyway.

So Spidouz, you should be ok!! And enjoy the VHX. I don't have one anymore, but they are one of the most versatile amps I have ever owned!!

 

[belensky]

I don't have one anymore, but they are one of the most versatile amps I have ever owned!!

How do you compare MK3 vs VHX? I have two OG mk1 in to two FL412, but thinking to put another Rig for live playing, VHX and 212 cab. Use to own FL212 very nice cab light weight and big sound, still miss it.

 

[VHTStark]

How do you compare MK3 vs VHX? I have two OG mk1 in to two FL412, but thinking to put another Rig for live playing, VHX and 212 cab. Use to own FL212 very nice cab light weight and big sound, still miss it.

Good question!! Tonewise, you can dial the VHX pretty close to the mk3.

Two things I noticed though:
1) At volume, any Herbert has much more headroom than the VHX. This is most noticeable if you do alot of downtuned stuff: the Herbert (any Mark) will just stay together better in the low end. I don't play a ton of super downtuned music....but this was where I noticed a difference.

2) The Herbert (as well as VH4), with its dial controls, actually allows a better fine tuning of the gain and tone, IMO. I swear dialing in my VHX, there was always a small middle ground between the .5 level jumps I could never fully reach. I know there was talk of making the value jumps smaller, but most players didn't want that. So....may not be an issue for you....was a deal breaker for me.

3) Herbert mk3 vs mk1: More similar than different, overall....but I found the mk1 to be a bit darker and more forgiving to play. The mk3 has some of the modern vh4 elements to it: brighter and tighter...but is stiffer to play than an old mk1.