solid state vs tubes

Discussion and topics that don't fit elsewhere.
GuitarBuilder
Posts: 227
Joined: Sat Aug 30, 2014 7:14 pm

Re: solid state vs tubes

Post by GuitarBuilder »

For those of you with an understanding of electronics, the following article may be interesting:

http://www.effectrode.com/signal-tubes/ ... -of-tubes/

What caught my attention was the observation on the use of negative feedback; the lack of it makes a compelling reason for tube circuit design.

RockmanCentralBob
Posts: 345
Joined: Fri Feb 06, 2015 2:10 am

Re: solid state vs tubes

Post by RockmanCentralBob »

Very interesting read, thanks for the link.

Interesting comments about the negative feedback, as that is one of the more popular mods done the the JVM series amps. The net effect of lower negative feedback is that the output tubes have less headroom and therefore clip sooner, so you don't have to run the amp on 10 to get output tube distortion. Many JVM owners add a 500K~1M pot in the feedback loop so they can find their "sweet spot" by increasing the resistance (and thus lowering the negative feedback). My original JVM 410H has the pot, but for my JS I hard wired in another resistor boosting the resistance to around 375K (for reference, the JS stock value is 100K and a JCM 800 is around 176K). The sound is truly beautiful!!

All the tube characteristics mentioned in the article are pretty spot on, some more subtle than others. Combined though, they due sound wonderful.

That said, I'm still convinced that solid state can sound very, very good. Again, at the end of the day the filtering applied is the elephant in the room and the most noticeable characteristic. As I said, the issue is all the other sonic artifacts that come with it that may or may not be noticeable to some people.

I still say though that the effort needed to make one piece of equipment (solid state) sound like something much simpler (tubes) is not without merit, but why go all around granny's barn to get there? If you want the sound of a cranked Marshall, just buy a damn Marshall and crank it!!! No need to reinvent the wheel. If you want to sound like Boston's first 2 albums, then just buy an MXR 6 Band EQ and an early 70's Marshall Plexi (the benefit here is that you can also sound like many other bands since they used the same thing). If you want to sound like Third Stage, then buy an X100 or a Sustainor. If you want to sound like Walk On or beyond, then get a Sustainor or Ultimatum. Use the same gear and you should find it much easier to find those sounds.

RockmanCentralBob
Posts: 345
Joined: Fri Feb 06, 2015 2:10 am

Re: solid state vs tubes

Post by RockmanCentralBob »

Over the weekend I decided to run a sine sweep on my Sustainor in order to profile the cab sim for the different modes.
The results were pretty interesting...

The Edge and Distortion really didn't come out that well, but the 2 Clean sims came out very nice!!
The Clean 1 profile sounds VERY good with my JVM on any of the clean modes, with increasing gain sounding similar to semi-clean or auto clean settings on the Sustainor.
It also sound great with Crunch and OD channels.

Some of you may have heard that SR&D had plans to release an all tube version of the Sustainor called the "Sustainor 2.0".
Unfortunately, Tom sold the Rockman line to Dunlop before it ever made it.
But in using this profile of the Sustainor with my JVM, I felt like this is what it would have sounded like.
Incidentally, it sounds an awful lot like the Ultimatum sound in general, and Tom's more recent live sound in particular.
MUCH more raw and aggressive than your typical Sustainor.

On a side note, Tom has mentioned that he does still have his old Marshall and even a Mesa Boogie, I believe.
I wouldn't be surprised if he's tried running the line out from the effects loop through a Sustainor.
If he has and it sounds anything like the profile I just created, I could definitely see him recording with that setup.

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Guitarvamp
Posts: 174
Joined: Fri Feb 28, 2014 1:02 am

Re: solid state vs tubes

Post by Guitarvamp »

Do you really think Tom was going the way of a tube hybrid unit? Why? I thought the point of the Rockman was to get away from tubes. Do you think this would have been a heart-felt move, or more that it was a marketing thing (everyone was putting out tube hybrid preamps at that time) along the same lines as the Distortion Generator?

Dale
Posts: 61
Joined: Wed Aug 27, 2014 12:40 pm

Re: solid state vs tubes

Post by Dale »

GuitarBuilder wrote: What caught my attention was the observation on the use of negative feedback; the lack of it makes a compelling reason for tube circuit design.
Headroom........something lacking in solid state.

RockmanCentralBob
Posts: 345
Joined: Fri Feb 06, 2015 2:10 am

Re: solid state vs tubes

Post by RockmanCentralBob »

Guitarvamp wrote:Do you really think Tom was going the way of a tube hybrid unit? Why? I thought the point of the Rockman was to get away from tubes. Do you think this would have been a heart-felt move, or more that it was a marketing thing (everyone was putting out tube hybrid preamps at that time) along the same lines as the Distortion Generator?
I'm absolutely positive about that.
I have an SR&D box for the full rack models, and listed on the box as content options were (CONFIRMED): Pro Bass, PGE-2, XPRa, Sustainor 20.
I was curious about this, so I asked Cedro (or Fred Sampson, Marketing Manager for SR&D, I can't remember which) and they explained it to me.

BTW, Tom's move to the Rockman wasn't necessarily about getting away from tubes as much as he was trying to get away from speaker cabinets and microphones.
There were some considerations regarding the effect of voltage on the output transformers of the amps when playing from venue to venue live.
But for the most part it was more about getting a consistent sound for recording because Tom works on these songs over a time span of years.
THAT'S where most of his frustrations were coming from because he couldn't get consistent sounds over the years because mic positioning has great effect on tone.