Amp Speaker tab versus Amp Graphic EQ

barhrecords said:
+1 I find the graph useful too for sure :)

I just was curious as to what the monitor graph represented.

For instance on another thread, there were speaker cab impedance graphs posted by redwire for some of their cabs.



The monitor graph in the speaker page would *not* represent those graphs or other impedance graphs provided or measured in regards to a particular cab and its associated IR.

Richard
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Its an excellent question,
The speaker graph has no meaningful scale to relate to that impedance graph. The controls that boost/cut the resonances are not label in ohms. the mid is labeled in db in axe-edit (that maybe a leftover from being copied from an eq monitor). I don't recall if there is a unit reference in hardware?


They sure do look like impedance graphs though.
 
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javajunkie said:
According the the firmware release notes it is an impedance curve graph
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Doh should have thought of going back there :)

To my ears / brain, it looks like an inverse of the impedance. I say that because spikes in the graph sound like boosts at that frequency to my ear, but I would think a higher impedance would not result in a boost at that freq?

Over my pay grade here :)

Richard
 
barhrecords said:
To my ears / brain, it looks like an inverse of the impedance. I say that because spikes in the graph sound like boosts at that frequency to my ear, but I would think a higher impedance would not result in a boost at that freq?
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Think of this in terms of voltage coming out of a real amp. Then, think of the 2 extremes - infinite speaker impedence (open circuit) & zero speaker impedence (short circuit). If the speaker impedence were infinite, the amp could deliver its full voltage capability (based on its design, power supply,etc.) to the speaker output jack. If the speaker impedence were zero, the amp could not deliver any voltage to the speaker output jack (shorted to ground).

The speaker impedence curve in the Axe is then somewhere in between those extremes.

Higher speaker impedences put less of a load on the amp. It can generate more voltage to the speaker. It can also do it faster - less power supply sag/compression. The amp sounds louder & punchier.

Lower speaker impedences put more of a load on the amp, which does the opposite of the above. The amp is quieter & more compressed sounding.
 
I think depends on your point of view. I think what you're seeing is speaker impedance as a function of frequency which is one portion of the conductive coupling between amp and speaker. The other portion comes from the transformer. From what I understand, when impedances match you get the most efficient power transfer from amp to speaker.
 
The XFormer High Freq and XFormer Low Freq are on the speaker page. But not the XFormer Match.

I think I was ass-backwards on ohms law (use the complex generalization for impedence vs. resistence), V = I * Z. So an increase in the complex impedance Z would be a higher V.

Richard
 
javajunkie said:
Considering the low, mid, and hi res goes from 0 -10. and the mid is listed as db. I would think it is the level of the resonance

Don't know what that line is. Does it exist in hardware?
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Sean,

Actually, the MID RES does NOT go 0-to-10 (like the LOW RES and HI RES do.) The MID RES resembles a FULLY parametric-EQ, in that it's gain units-of-measurement are in db's, AND the MID RES range is from (-6.0 to +6.0 -->I.E. CUT or BOOST!) BTW, I checked this on the hardware's screen, but NOT in Axe-EDIT.

I know that Cliff assures us that it's NOT really EQ, but more of an impedence/Power-Amp graph, so I was wrong in my explanation...I'm still learning - lol!

BTW, I think of the "line" as a sort of graphical-representation of "speaker-thump!"

Bill
 
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billmeedog said:
Sean,

Actually, the MID RES does NOT go 0-to-10 (like the LOW RES and HI RES do.) The MID RES resembles a FULLY parametric-EQ, in that it's gain units-of-measurement are in db's, AND the MID RES range is from (-6.0 to +6.0 -->I.E. CUT or BOOST!) BTW, I checked this on the hardware's screen, but NOT in Axe-EDIT.

I know that Cliff assures us that it's NOT really EQ, but more of an impedence/Power-Amp graph, so I was wrong in my explanation...I'm still learning - lol!

BTW, I think of the "line" as a sort of graphical-representation of "speaker-thump!"

Bill
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Yes, I mentioned the db on the mid earlier. I saw that it was -6 to +6db in axe-edit.
I wanted to confirm in hardware. It is that way in hardware.

The line does not exist in hardware. I wouldn't read anything into it.
 
barhrecords said:
The XFormer High Freq and XFormer Low Freq are on the speaker page. But not the XFormer Match.

I think I was ass-backwards on ohms law (use the complex generalization for impedence vs. resistence), V = I * Z. So an increase in the complex impedance Z would be a higher V.

Richard
Click to expand...

Higher v? Or lower current?
 
Thumping man!

javajunkie said:
Yes, I mentioned the db on the mid earlier. I saw that it was -6 to +6db in axe-edit.
I wanted to confirm in hardware. It is that way in hardware.

The line does not exist in hardware. I wouldn't read anything into it.
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Hi Sean,

Is my assessment of the whole LO RES concept (amount of "speaker-thump") feasible? Just curious if I'm associating the concept properly to what I hear?!?

Thanks for your input/opinion!

Bill
 
billmeedog said:
Hi Sean,

Is my assessment of the whole LO RES concept (amount of "speaker-thump") feasible? Just curious if I'm associating the concept properly to what I hear?!?

Thanks for your input/opinion!

Bill
Click to expand...


That what Im tuning for. Amount and location of the thump. I will also move the freq out of the way when it muds up palm mutes
 
All I seem to do by playing around with the Lo Res is make a decent patch sound like moist ass. I hear the thump, but I don't like it. Axe through USB into Adam A7's.
 
Mott said:
All I seem to do by playing around with the Lo Res is make a decent patch sound like moist ass. I hear the thump, but I don't like it. Axe through USB into Adam A7's.
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Following is a post I did on another thread; but try my method of dialing that tab. It works well for me:

The Speaker Resonance tab to me in my words is the way to dial in the symbiotic relationship between the power amp (transformer/output tubes/rectifier) to the speaker/cab *and* vice versa. They are a system, not independent. Small changes to the resonance has the effect of dialing in the amp/cab as a system. If you spend 30 minutes of critical listening on a reference level system while making small changes, you'll hear it and added to the visual addition of a graph... you can now 'see' what you 'hear'. You will learn very fast what works, how it works. After that first "learning" tweak period, you'll spend a minute or less dialing it from there on out.

My process is this: ... bump the low end HZ slightly, listening. When you hear it 'blow up' on the low end, back it down. Then turn the low end resonance up till it blows up again, then slightly back off. Then change the "Q" and balance between the level and the Q till it is fat, but tight. Then on the high end just turn the level up slightly, a bit at a time... it'll start to explode on the top end, back off slightly. Done. Mess with the middle by turning it up a touch at a time... often this gets left at zero in my world. **Added note: these changes are absolutely tiny, small increments. The key is to trust your ear. When it sounds like "too much" trust that instinct and back it down. You might only end up a few hundredths of a value from stock; but it will be worth it's weight in gold... trust me.
 
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