So Anyway...

Mr Grumpy said:
I have been waiting for the Marshall solid state I bought for the last 17 days.
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Sorry, I missed the bottom of your post. I really think that folks are not extracting much of the benefit of that "tube sound" at low volumes. I think the magic starts to happen at or just before natural breakup. This is often conflated with liking the built in gain channels of an amp. If my premise is correct, it is possible that the MG30 will be plenty convincing to you.

If others feel there is more offered at low volumes from tube amps over SS, I would love to learn more
 
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smitty_p said:
So, anyway...

I’m taking advantage of my recent violent stomach illness to attempt (emphasis on “attempt”) a lifestyle change.

My sense of taste is still sort of messed up and I avoided caffeinated beverages while I was sick. So, now I’m pretty much weaned off of caffeine. I admit...I am sleeping better.

I’m going to take this opportunity before my full sense of taste returns to try switching over to decaf.
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Sorry for your illness. Glad you are feeling better. During the times I avoided caffeine, life was more even...less peaks and valleys in energy and demeanor, much like other drugs. You may enjoy the change
 
Gahr said:
Good to hear you are over it. My wife and oldest kid have been sick with a really heavy cold all week, but are better as of yesterday. Me and my youngest are starting to feel it now, just in time for the Easter holidays. We have the whole week off, and it would be just typical if it is screwed up by being sick. The weather is awesome, our new back garden terrace is done, we have bought some new plants for the garden and have four rose bushes that need replanting. There is no effing way I am willing to get sick right now!
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Hope he dodge the bullet
 
RVA said:
If others feel there is more offered at low volumes from tube amps over SS, I would love to learn more
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Well, that's one thing I wanted to find out by trying the MG30 - many folks are saying that ss is very good, so I'm giving it a go.

My 1 watt Randall had no clean, broke up really early, so you could get nice tubes sounds at low volume (obviously the volume knob working with the gain knob is important for this). My 5watt Bugera and Marshall DSL both had low wattage settings, so you could get good tube sounds from them, but both of them sounded better on the 5watt setting where you could only just get nice sounds at low volumes, but again only on channels which had a volume and gain knob, and you couldn't get the full variety of sounds. As Gahr said in another thread, a bit of volume certainly helps to sweeten the sound to be most enjoyable.

I personally believe that the tube sounds, even at low volume, while not giving you the full range of possibilities from the amp or the best sounds the amp has to offer, are still somewhat better than ss sounds. But, I am open to being proven wrong by this new MG30 if it ever arrives.

Actually, I might buy a 1 watt dsl head and test this out directly.
 
I liked the little Solid State Marshall head I had ---no negatives-- just the larger 100watt head came into the picture --- and space being at a premium in the doom room somethings had to go---

The Marshall CODE was the only Marshall I think I ever DID NOT LIKE-- the souinds that came from it seemed fake-- and the software on 2 of them never worked right or synced with phones etc etc.
 
Robert Herndon said:
What's the biggest difference you notice in those two Reaper's???
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None really now, I’ve only ever had them working together in a 2x12. The spot in the cab was previously taken up by a WGS ET65, which now resides in a 1x12 cab.
The difference that the 55Hz speaker introduced was a fatter low mid focus. That’s what I wanted from that cab for gigging with smaller tube heads.
 
Thatbastarddon said:
None really now, I’ve only ever had them working together in a 2x12. The spot in the cab was previously taken up by a WGS ET65, which now resides in a 1x12 cab.
The difference that the 55Hz speaker introduced was a fatter low mid focus. That’s what I wanted from that cab for gigging with smaller tube heads.
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That's what I perceived in my DSL40C speaker swaps too.
 
So anyway, I stumbled across an amazing explanation of the differences between 12ax7, 12au7 and 12at7 at harmony central.

The various 12A?7 tubes all have different gain ratings.

Gain Factor
AX=100 mu
AT=60 mu
AY=45 mu
AU=19 mu

But a lot of people look at these numbers and think..."that's all." And it's not.

Unfortunately, there is also this:

Plate Resistance
AX=80K ohms
AT=10.9K ohms
AY=25K ohms
AU=7.7K ohms

While it doesn't hurt these tubes to be swapped in for a 12AX7, it's not ideal either. You want to know why these tubes sound clean? It's because running a 12AU7 or 12AT7 in a circuit designed for a 12AX7 biases them cold, damn near sterile. You aren't actually getting 60 mu out of a 12AT7 in a 12AX7 slot, and you aren't getting anything close to 45 mu from a 12AU7. Preamp tubes are cathode-biased (well, after the '50's anyway) but a big jump in plate resistance will put the tube out of bias range.

Now there is an exception, the 5751 was designed to have a mu of 70, and a plate resistance identical to a AX, the 5751 tube was specifically designed to be a lower-gain, plug-in replacement for the 12AX7. (it is not however considered an ideal replacement for the 12AT7, despite their similar gain factors)

Designing an amp is all about biasing the gain stage and correcting the curve (for a flat EQ) for each tube. Unfortunately, you can only do that for one exact brand of one exact tube when designing the amp. Which is why some builders (ken Fischer, Dr. Z, Bogner) are very specific about what tubes they made their amps for.

I should add that, obviously, almost all these tubes are designed other names by other companies or for other purposes. For example a 12AX7 was available as 7025 (JAN/Military), ECC83 (England), CV4004 (France?), etc. Generally, many companies had their own designations and suffixes and prefixes to make their product stand out.

As for the original question, tube rolling is equivalent to seeing what non-factory spec aftermarket part has what effect in hampering your high-end European sportscar to give it more "individual character." It's only go to run it's optimum best with a handful of the right parts, but people like to tailor feel to their own specific ergonomics. I'm not against this per say, but (going back to amps) its one thing to voice an amp by through off its curve correction with a tube from another brand and a whole other thing to use a tube type that the isn't working 100% wherever you put it.

Using a lower gain preamp tube early on means you aren't boosting the signal as much as the start of the amp circuit as normal, so less signal goes further on down through the amp, meaning there is less signal to be boosted latter and less signal to cause clipping. It's like taking to familiar cliche of a snowball rolling down hill...getting bigger and bigger...and just starting with a smaller snowball at first, and ending up with a smaller snowball in the end. It is very similar to just turning down the Volume (or Gain on a Master Volume amp), it just achieves it in a different way with slightly different results.

IMHO, if you want a cleaner preamp, raise the B+ voltages to preamp tubes, don't swap in different tubes. You want a dirtier (browner) preamp, lower preamp B+ voltages (this will have the additional benefit of adding touch sensitivity), there are two dozen other changes to can be made in the preamp to tailor it to taste (easier to do in a old Fender than say a complicated Bogner). Though using a 5751 in any 12AX7 place is perfectly fine to try for a little lower gain, it'll perform well.

The negative side-effect using lower resistance tubes without tweaking the circuit is you lose dynamics and touch sensitivity (the latter is something BF/SF Fenders don't have a lot of anyway) and trade off spontaneity and responsiveness for more sterile, stiffer cleans. It's a hack mod. Plus, there is, of course, Volume knobs on the guitar and amp, and on old Fenders a "padded" (attenuated) input #2 for each channel.

(wow, long, and I'm sure the tube rollers are going to beat on me for it, but remember, I take no responsibility for typos, I'm a lousy typist)
 
So anyway, I just got a matched pair of Russian 6p6s from an ebay seller in the Ukraine and one is DOA.
the seller messaged me back quickly and is supposed to send me another with matching specs.

20190414_194515 2.jpg
 
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