Never imagined a combo's cabinet could make such a huge difference

[12AX7]

Long story but i'll try and make it short as possible. 2 amps, one my first build the other my last. Gave the last away a year or so ago to a friend's kid and have been working on making my original better. Got the newer build back recently from friend's kid who gave up playing. These 2 amps sound very different. The one i just got back is a E34 and the original build a 6V6, but aside from the tubes and trannys there are very similar with duplicate cascaded preamps. I had tried to make the newer el34 amp sound as good as the 6v6 amp for a long time but they always sounded worlds different. So i get the old amp back and decide to put the 5v5 amp's trannys and all else needed to be the same into the el34 amp and make a duplicate amp from it. I did this because the el34 amp;s guts were clean and new and the 6v6 amp is a slop fest beyond your wildest dreams due to endless experimentation. So here i have the el34 amp with the same preamp and now the same trannys and tube. Still sounds like it always did as a el34 amp ! I was shocked and disappointed and after a day of work to do that swap i then swapped it all back ! So now i have the 6v6 amp back up and corking and theres that tone i love again. A ton of mids ad round smooth highs all in balance. The el34 amp was tons of very high range treble content, no mids to speak of and insane amount of bass. Scooped as can be which killed the marshall tone that the circuit was modeled after, which is why i didn't like that amp.

Heres where it gets weird. The 6v6 amp is built into a small old marshall 20 watt solid state combo cab/chassis i stripped. All particle board tho i made a ply baffle for it. The el34 amp i built the cabinet myself out of solid pine and ply baffle and it;s about 25% bigger than the little marshall combo cab. So i figure i may as well put the 6V6 chassis into the big pine combo cab and i spent 1/2 the day modifying the 6V6 amp chassis to bolt into it. When i turned it on i was shocked.....damn amp sounded like the el34 amp !!! No mids, all highs and too much low end ! the difference in those two amps that was HUGE, and the reason i could never get the 34 amp to sound like the 6v6 wasn't the circuits, it was the cabs ! The cabs actually trumped the circuits in how much different the tone was. I could do anything to either of those amps and i did. I experimented endlessly with them, but they always sounded the same. Little changes yes, but the basic character of each amp stayed the same no matter how much i changed them. And now i know the largest influence on them was the freakin cabs !  And if thats not weird enough, the el34 amp's pre had a lot more gain than the 6v6 even tho the pre was exactly the same. I spent years trying to figure that out even going to the length of dropping the voltage and filters in the 34 amp to mimic the smaller amp's PSU and voltages. Didn't do a thing. But when i put the 6v6 amp into the pine combo can, i swear to you the gain was now like the el34 amp's was ! I don't expect anyone to believe me because i would have never believed it myself if i hadn't heard it for myself.

[John]

When you switched cabs, I assume you were also switching speakers.

[12AX7]

Yep. Using the same 100w celestion art all times.

[12AX7]

Wood does have a resonant frequency. This has been a huge debate, but it does. Simple as that.

No doubt. It would be foolish to debate that. I just never thought it could make this degree of difference. I learned a big lesson with this after a lifetime of being clueless. I will never again look at a amp's tone the same way again ! I will always be looking at the cabinet and wondering how much of what i hear is that. I also learned that i think i refer particle board, a material i always thought of as responsible for lousy tone. I recently read that it's actually very neutral which can be a good thing. The pine just absolutely robbed me of the mids i love about that amp.

[jojokeo]

I've heard that neutral sounding comment about "particle" board but rather I think you are meaning to say MDF? Medium density fiberboard??? It's actually very heavy and dense.
 
However, many people rave about Fender's pine boxes of yore and especially Gerald Weber or Kendrick amplification. He speaks glowingly about not just voidless and knot-less pine but also "old and aged yellow sugar pine"...now how can that not sound good? It makes me want a scoop of it as in ice cream cone!
 
I just bought a couple tweed cabs from my guy that was also commenting on some special pine that he had and was going to use for mine. I've gone through about 4 different speakers so far and I don't really notice a scooped tone with them that you are describing with yours?!
 
On cab making - this is an art unto itself and size matters! Just like wood, resonant freq, open/closed back, ported or not, and especially internal volume is also very important being ~55 liters.
 
On another forum by a lot of members and through a lot of discussion and participation, a single 12" cabinet was designed among everyone. Weather 5/8" or 3/4" was to be used or even how it was joined - if they are miter/finger/box/butt/dowel/dovetail/biscut-joined without bracing,. It was interesting to know of the many various woods and technical information there is about density, hardness, grain, modulous elasticity, resonances, then the size ratio was decided and came up to be 9x18x21 and those were inner dimensions. Freq roll-offs and such were calc'd and then using at least 12 to 15 speakers of all of our most favorites. Then there were measurements made and charted on graphs using software with a long list of various descriptions made based on frequency ranges to describe things commonly to evaluate everything. It was decided that a small hole off center for the back appx 5" diameter had advantageous benefits to the others (being open, partially open back, or closed back).

[12AX7]

I dunno...particle board, MDF, whatever ya  wanna call it it's wood chips/dust and glue. All i know is the mids are worlds bigger and thicker than the other one. The other one however has a overall huge sound that sounds more refined. just no mids and too much low end. I think i would prefer it if the mids were there, which has me thinking...i wonder how it would sound with a V30? After all, the V30's are often said to lack low end which might fix that issue. And they are also very middy which means it could potentially cure that cab's 2 issues and leave me with a bigger fuller more quality sound. But alas, it's one of those things i am just to jaded to try because more often than not it doesn't work out and i'm stuck with a speaker that will just take up closet space forever. (ever check the cost to ship a speaker?)

[zendragon63]

Couldn't agree with you more 12AX7. I have built half dozen cabinets--all of the same dimensions--but with different woods and by far the most best sounding was mahogany and worst was maple. The control being the amp itself--being easily interchangeable into said same dimension cabinets.

I personally like the look and drama of the wood and grain. Surprisingly one that turned out really well tonally was that of canarywood. Go figure. Like Jo says, there are also all these variables to consider that affect the response i.e. dimension ratios, overall cabinet volumes, open or closed back, baffle mounting, etc. And any combination thereof. FWIW, the few I have built from particle board--even though not very showy--at least seem more predictable in frequency response. Regards

dennis

[12AX7]

Heres another observation thats kinda odd. I was using a celestion 100 watt speaker but the speaker i have used for years before i pulled this amp out of storage a couple months ago was a EV12L. I been experimenting and i found that with the celestion in the pine cab i get a lot more low end than with the EV in that cab ! I never found that speaker to have more lows than a EV in anything i've ever used em in. Strange. I did however put a choke in the amp and found it doesn't fit in the little cab so i moved it since i last tried the pine cab. could choke location effect tone? I have to move it right up next to the power transformer almost touching it.

[Willabe]

I dunno...particle board, MDF, whatever ya  wanna call it it's wood chips/dust and glue.

MDF (medium density fiberboard) is just saw dust glued up, brown in color, very smooth and very heavy.

Particle board has wood chips in it, is a natural yellow/white color and is not as smooth as MDF, nor as heavy.