Supply Filtering

[chief mushroom cloud]

your not wrong,
for a guitar amp it doesnt go so well, but for a relativly simple tube pre for Hi-FI
its one approach that really does affect the subjective quality of the amp.
its also fairly common, build a tube pre or a home stereo amp and
explore it yourself. Ive built a small stereo for the TV, DVD's end up being what gets
listen'd to the most, and sound tracks are very demanding.
You really do end up chasing after the detail, Its another way to follow your ears.
you might be suprised. Its just another amp after all.

now that I agree w/
I would tweek until I could get great detail in a good hifi toob amp

but in a guitar amp.....well, I'll shut up

[Alexo]

Interesting discussion, as usual...

Reminds me of some debates that take place in the recording community - the human range of hearing extends to about 20khz if you're lucky, yet there are digital recording interfaces that accurately record and reproduce music up to 48khz, even 96khz.

Many people argue that this is a waste of money (and digital storage space), especially since the final medium - a CD - can only produce frequencies up to 22.5khz. But even if we can't hear what's going on at 80khz, you could have an acoustic guitar track and a sousaphone track that are each producing harmonics in that range. The harmonics can interact and produce "sub-harmonics" that do come out in the audible range. But if those upper harmonics don't make it to the mixing board, their sub-harmonics won't make it to the CD, and this can be what separates a 3-d sounding recording from a flat, 2-dimensional one.

So even if there are other factors that chop down the frequency response of your rig before it reaches your ears, it is conceivable that having good hf response in the amp can contribute to a "better" tone, just as filtering out inaudible switching noise can help avoid audible sub-harmonics produced by the interaction of that noise with the musical signal.

But we could argue all day about how many angels can dance on the head of a pin. The only thing that matters is how it sounds.

[WILLIAMEON]

The cleans were breaking up, now they are nice and tight. Overdrive about the same. this has the transformer upgrades. adding the rest of the 124 mods today. The pre-amp boost circuit seems to do little, if nothing.
Would like to switch it to mid-boost instead.
The special is the best combination of clean and overdrive that I have run across so far.
thinking about the 100
Building a attenuator to go with my wreak clones and finishing off a few old projects.
Great site and people!

[headstack]

Interesting discussion, as usual...

Reminds me of some debates that take place in the recording community - the human range of hearing extends to about 20khz if you're lucky, yet there are digital recording interfaces that accurately record and reproduce music up to 48khz, even 96khz.

Many people argue that this is a waste of money (and digital storage space), especially since the final medium - a CD - can only produce frequencies up to 22.5khz. But even if we can't hear what's going on at 80khz, you could have an acoustic guitar track and a sousaphone track that are each producing harmonics in that range. The harmonics can interact and produce "sub-harmonics" that do come out in the audible range. But if those upper harmonics don't make it to the mixing board, their sub-harmonics won't make it to the CD, and this can be what separates a 3-d sounding recording from a flat, 2-dimensional one.

So even if there are other factors that chop down the frequency response of your rig before it reaches your ears, it is conceivable that having good hf response in the amp can contribute to a "better" tone, just as filtering out inaudible switching noise can help avoid audible sub-harmonics produced by the interaction of that noise with the musical signal.

But we could argue all day about how many angels can dance on the head of a pin. The only thing that matters is how it sounds.

late to the party as usual
Would some one mind explaining the production of audible subharmonics from hf harmonics above (pulling numbers out of hat) 24kHz?

I find this an exciting concept not considered as part of the audio sound stage.

Just didn't dawn on me.

I recall reading that while there are things going on above our normal hearing range, these frequencies apparently still affect us through conduction.

This is why a live symphonic crash makes us shiver with excitement, gives us goosebumps, while the recorded equivalent typically is a bit less thrilling.

I stumbled on this thread looking for film cap piggbacking info with consideration to a tube mic power supply I am cleaning up, and for a couple guitar amps and two power amps.

Looks as though the power amps are the only two viable candidates?

Thanks for a great discussion folks, interesting as always and far less brainwracking than slutty.

[Andy Le Blanc]

That gets into reproducing the entire sound stage and experiencing sound as it natural occurs.
The real goal of HIFI is to "trick" your ears and place you "there".

You start running into practical issues at both extremes of the hearing range.
There's a cellphone chirp designed to be out side the hearing range of the average adult, the kids can hear it.

I handled an artist once who could hear the RF oscillation from a crappy amp out of the monitor tweeter.

I had another fella who got physically sick if the subs were extended below 50hz.

You also have to go to extremes of gear and power to get it.
And nobody really wants to hear a cymbal crash except the guy up in the tympani section.

To get sub, infrasonic, you need power and a device that will handle the requirement,
its why you see these big walls of bass horns at concerts.

The top end is easier, the efficiency of the devices are over 100, but your still not gonna see a practical response over over 22khz. even good measurement can become a practical issue.

So you do the best you can, and another issue becomes... just because you can doesn't mean you should. Air can be fatiguing and sub a real nuisance.

you can get away with a range of 100 to 10k and be very natural.
Practical PA application will get you 50 to 12k., you'd be surprised once you get in there and meter things.

Theres one venue I run that I can force the system with EQ to RTA flat from 20 to 20k, nice accomplishment but not overly practical for live FOH.

and the same issues exist for home listening rooms...