I've tried adjustable negative feedback.
No negative feedback is nice for getting a 'broad' sound in a duo or trio setting, for instance.
I dialed in more negative feedback for louder settings, where the amp needed to stay cleaner at louder volumes.
However the negative feedback is in the output stage from speaker output to phase splitter 'tail'.
Incorporating adjustable NFB into a preamp would take more work.
No negative feedback is nice for getting a 'broad' sound in a duo or trio setting, for instance.
I dialed in more negative feedback for louder settings, where the amp needed to stay cleaner at louder volumes.
However the negative feedback is in the output stage from speaker output to phase splitter 'tail'.
Incorporating adjustable NFB into a preamp would take more work.
What I suggested with respect to bracing a cab doesn't get in the way of anything you like. It just gets rid of the stuff that when its gone you suddenly realize was giving you a muddy, boomy, out of control sound. Also, I always preferred open back until I fixed the damping of my cabs. The cab I use most has three removable back panels so it can be used in multiple different open cab configurations. Once I got control of some of the worst of sound radiating off the back and and sides of the cab, then it started to sound more like my actual guitar, only better. At that point I tried the different open and closed cab configurations and found at that point the close cab sounded best. My daughter came came over to visit for a week and she also plays guitar. She started playing it for hours because it sounds so good she just didn't want to stop playing. It was quite a revelation for me. I didn't expect that much benefit from fixing cab resonances. Later a friend who is a full time pro high end audio designer who has done work for a number of well known name companies. I told him about what I found and he said he has another friend who has been doing about the same type of thing. My friend emphasized that not overdoing the damping is key. You want some musical sound from the cab, just like you do from a semi-hollow body guitar body vibration. Over damping that is bad. But if you do it right to the cab it sounds great. Only downside is the time and effort to do it, and the final weight of the cab.
That does make total sense. It sounds like you've put a lot of thought, time and effort into figuring that out, so I should listen!
The weight from extra bracing does worry me, but it does always seem that a heavier cab sounds better than one of these overly resonant, lightweight cabs you see nowadays.
You're also right that the speaker (cab + driver) you use has a lot more to do with the sound than the amp circuit you use. I once took a nice, big old cabinet with a 12" and an 8" and drove that with a dinky little solid state practice amp. The combination sounded GOOD!
However, in this case I'm thinking of a direct-to-computer kind of thing. I guess I could use a speaker emulator or something. I don't really want to spend the money on that, though.
I eventually want to put together a smaller gigging rig, with something like a simple 25 to 35 watt head (just volume and tone controls would probably be enough) and a good sounding 1-12" cabinet of some kind.
What kind of speaker driver do you use in your sealed cab? Is it a standard 'guitar speaker' with a thin paper cone, paper surround and smallish magnet , meant for open back or reflex loading? (think vintage Jensen or Celestion.) Or is it a more modern kind of speaker with lower sensitivity, a bigger magnet, and a more even frequency response, more like a good sound reinforcement mid-woofer? (Think JBL, Altec Lansing, or a beefy Eminence driver.)
The weight from extra bracing does worry me, but it does always seem that a heavier cab sounds better than one of these overly resonant, lightweight cabs you see nowadays.
You're also right that the speaker (cab + driver) you use has a lot more to do with the sound than the amp circuit you use. I once took a nice, big old cabinet with a 12" and an 8" and drove that with a dinky little solid state practice amp. The combination sounded GOOD!
However, in this case I'm thinking of a direct-to-computer kind of thing. I guess I could use a speaker emulator or something. I don't really want to spend the money on that, though.
I eventually want to put together a smaller gigging rig, with something like a simple 25 to 35 watt head (just volume and tone controls would probably be enough) and a good sounding 1-12" cabinet of some kind.
What kind of speaker driver do you use in your sealed cab? Is it a standard 'guitar speaker' with a thin paper cone, paper surround and smallish magnet , meant for open back or reflex loading? (think vintage Jensen or Celestion.) Or is it a more modern kind of speaker with lower sensitivity, a bigger magnet, and a more even frequency response, more like a good sound reinforcement mid-woofer? (Think JBL, Altec Lansing, or a beefy Eminence driver.)
Celestion Gold, 8 ohms, 12", 50W, alnico magnet. A great vintage sound. To be clear, have other speakers I could have used; just happen to like this one best for guitar.
Also for moving the amp and speaker around comfortably, still using an old version of folding truck something like this (300lbs rating):
https://www.bhphotovideo.com/c/product/43600-REG/Remin_S600_Super_600_Cart.html/?ap=y&ap=y&smp=y&smp=y&store=420&smpm=ba_f2_lar&lsft=BI:514&gad_source=1&gclid=Cj0KCQiA7NO7BhDsARIsADg_hIZ0lhGrtwHLxzPF4qzz4wH8svWueTNCcs3DWi6v5YbQgF-B0dkuKWYaAsqcEALw_wcB
https://www.bhphotovideo.com/c/product/43600-REG/Remin_S600_Super_600_Cart.html/?ap=y&ap=y&smp=y&smp=y&store=420&smpm=ba_f2_lar&lsft=BI:514&gad_source=1&gclid=Cj0KCQiA7NO7BhDsARIsADg_hIZ0lhGrtwHLxzPF4qzz4wH8svWueTNCcs3DWi6v5YbQgF-B0dkuKWYaAsqcEALw_wcB
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Oh does that ever bring back memories! Back when I lived in NYC, I used to use one of those to get to gigs.
Back then the cabs had huge trunks (Checker and Crown Vic) so I could fold down the cart and fit my combo amp in the trunk. But man... those NYC potholes! I'm amazed the amp made it through those years (it still works fine).
I think now that I'm older, I'd want to go a lighter...
Some players use two small amps, or a small amp head with two small speaker cabs, placed a few feet apart. Better coverage negates the need for a high sensitivity single speaker. Two 10" cabs would probably work well. Or a 2x8" cab with large-ish dimensions?
But I definitely want to go light...
Back then the cabs had huge trunks (Checker and Crown Vic) so I could fold down the cart and fit my combo amp in the trunk. But man... those NYC potholes! I'm amazed the amp made it through those years (it still works fine).
I think now that I'm older, I'd want to go a lighter...
Some players use two small amps, or a small amp head with two small speaker cabs, placed a few feet apart. Better coverage negates the need for a high sensitivity single speaker. Two 10" cabs would probably work well. Or a 2x8" cab with large-ish dimensions?
But I definitely want to go light...
I went through that as a bass player in the 80's 90's and 2000
Specially in the 2000 era is where you see small cabs.
And guys thought it would be easier to carry 2 cabinets.
Either 1x12 or 1x15
They didnt seem to get a small low cabinet is hard to roll on wheels.
Basically impossible without bending over.
Now you have to lift and carry 2 cabs 2 trips 2 things to get through a car opening.
I could slide and drop a 8x10 and roll it in before they made it back for
the second cab.
I never carried a cabinet. Rolled it.
Why you see dented grills, they carry them wrong.
3/4 inch wood is the standard basically.
You just use 1/2 inch wood and it gets lighter.
I dont have any magic insight on wood species.
At the wood store they might have 2 or 3 different sheets of 1/2 inch.
I slide and pick up all the choices. Whatever is lighter. There will be one with big difference.
That one ...Buy it, lol Science
With guitar the size of a 1x12 or 2x12 really wont change much.
But I have built some very light cabinets the same way with 1/2 inch.
And going open back does really lighten it up a little more. less wood
Or go 10" for 2x10 Eminence Legend 1028k is about the lightest speaker
you can get and sound ok. The neos kinda suck
I would look at Orange Micro Terror 20 watts.
It is basically a lunch box and light enough to light up a 2x10 or 2x12
Many moons ago Traynor made a bassman like combo.
Was 4x8 not 4x10 so it is small but can get loud if you need it.
Do the same with a light 1/2 inch ply cab, open back
Specially in the 2000 era is where you see small cabs.
And guys thought it would be easier to carry 2 cabinets.
Either 1x12 or 1x15
They didnt seem to get a small low cabinet is hard to roll on wheels.
Basically impossible without bending over.
Now you have to lift and carry 2 cabs 2 trips 2 things to get through a car opening.
I could slide and drop a 8x10 and roll it in before they made it back for
the second cab.
I never carried a cabinet. Rolled it.
Why you see dented grills, they carry them wrong.
3/4 inch wood is the standard basically.
You just use 1/2 inch wood and it gets lighter.
I dont have any magic insight on wood species.
At the wood store they might have 2 or 3 different sheets of 1/2 inch.
I slide and pick up all the choices. Whatever is lighter. There will be one with big difference.
That one ...Buy it, lol Science
With guitar the size of a 1x12 or 2x12 really wont change much.
But I have built some very light cabinets the same way with 1/2 inch.
And going open back does really lighten it up a little more. less wood
Or go 10" for 2x10 Eminence Legend 1028k is about the lightest speaker
you can get and sound ok. The neos kinda suck
I would look at Orange Micro Terror 20 watts.
It is basically a lunch box and light enough to light up a 2x10 or 2x12
Many moons ago Traynor made a bassman like combo.
Was 4x8 not 4x10 so it is small but can get loud if you need it.
Do the same with a light 1/2 inch ply cab, open back
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Going with neodymium magnet speakers can lighten the load considerably over the usual ferrite slab with the same magnetic force. Neo magnets are even more powerful per weight than Alnico.
As a general rule, doubling the cone area gains +3dB sensitivity, the equivalent of doubling amplifier power.
2x8" will "outgun" one 10", but is a little shy of 1x12".
A 100dB 1watt/1meter sensitive speaker would require a 10watt amp to do 110dB, 100 watts for 120dB- about the level of a loud(ish) snare drum
A 15" guitar speaker has around 136 square inches (890 sq.cm.), sensitivity ~103dB.
A 12" ~ 84 sq. in. (545 sq.cm.) sensitivity ~101dB
A 10" ~ 57 sq. in. (366 sq.cm.) sensitivity ~98dB
An 8" ~ 36 sq. in. (231 sq.cm.) sensitivity ~96dB
A 6" ~ 22 sq. in. (140 sq.cm.) sensitivity ~94dB
Drivers with more bass tend to be less sensitive than the above.
Art
Maybe good to get two cabs. One for casual gigging where most of the audience is beyond the critical distance anyway. Mostly those people are hearing room reflected sound.
The other cab would be for recording and for important gigs where maybe there is a high quality PA for mic'ing up the guitar cab.
The other cab would be for recording and for important gigs where maybe there is a high quality PA for mic'ing up the guitar cab.
