Output 3 level

akmojo67

akmojo67

Member
Might be a possible bug? Output 3 is considerably quieter now than prior to the official release. I use output 3 for power amp and cab. I had the levels even with output 1 prior to update but now across the board, in all pre-sets, it is considerably lower. Can someone confirm?
 
Yes, you are right. What I did was level output 3 by the meter to equal with output 1 in the last beta, which is about a 20dB difference. After the last release, the meter shows the levels aren't the same but after listening carefully, I think that the meters are off not the volume with this release. Thanks for the reply's
 
I set my Output 3 level to +18db to send to my poweramp. They have always been quieter than Out 1 and Out 2.
 
This ↑. By default, Outputs 3 and 4 are set up for unity gain output with their front panel Output knobs wide open. Makes external FX Loop and 4CM setups easier. Have to use the +18dB Boost/Pad in the I/O menu to get them closer to what Outputs 1 and 2 can offer.
 
I have a question in this. I thought I understood this lol - but the relationship between meter output levels (that are lower but compensated for with with the boost in I/O) and the physical volume jump when increasing the level on the GEQ which has no effect on the meters....

if i read things right - a 7db (just over) gain gives equivalent of -10 dbm and 18.5 gives +4 dbm.

Now - firstly I cant find the input specs for a Seymour Power Stage 170 so dont know if Im aiming for -10, +4 or some instrument level between the two. That would help lol.

So - to match the Powerstage, where should I set the pad/boost in i/o - and do I need to boost the gain level in the output GEQ?

Thanks all
 
paulmapp8306 said:
I have a question in this. I thought I understood this lol - but the relationship between meter output levels (that are lower but compensated for with with the boost in I/O) and the physical volume jump when increasing the level on the GEQ which has no effect on the meters....

if i read things right - a 7db (just over) gain gives equivalent of -10 dbm and 18.5 gives +4 dbm.

Now - firstly I cant find the input specs for a Seymour Power Stage 170 so dont know if Im aiming for -10, +4 or some instrument level between the two. That would help lol.

So - to match the Powerstage, where should I set the pad/boost in i/o - and do I need to boost the gain level in the output GEQ?

Thanks all
Click to expand...
https://www.seymourduncan.com/image...l Amp Quick Start Guide by Seymour Duncan.pdf
 
Hubertus said:
https://www.seymourduncan.com/images/User Guides/PowerStage 170 Pedal Amp Quick Start Guide by Seymour Duncan.pdf
Click to expand...
That doesnt answer the question.... Is it -10dbu, 4dbu or some other level (signal level?).

I did look at that - and it SEEMS to indicate just use OP3 of the AFX with no boost - as that OP is designed for unity gain which is what you get plugging a guitar straight in? would that be fait to assume?

The pad level makes no difference to volume.... Only the OP1 block level, Global GEQ or output knobs do.

Let me be clear what Im TRYING to achive. im trying to gain stage things so when the meters show 0db in the AFX, and I have the front know max'd out - the power amp is running about 3db below clipping.

Im not normal lol
 
It is a tad strange and Im trying to wrap my head around the new toy...

Changing the pad/boost level results in changes to the OP meters (both on the AFX and in Axe-edit) which Id expect BUT it has absolutely no effect on the volume I get from the amp. If I change the OP level the meters also go up - and then I DO get a change in volume.

Theres is something more to this than a pure signal level the amp is getting - and im not sure what that is - or why its happening. When I understand how it all works together Id have a better shot but that might take a while. For Now I just need to make sure I dont blow anything yup lol - but get the gain staging and maximum levels limited.
 
paulmapp8306 said:
It is a tad strange and Im trying to wrap my head around the new toy...

Changing the pad/boost level results in changes to the OP meters (both on the AFX and in Axe-edit) which Id expect BUT it has absolutely no effect on the volume I get from the amp. If I change the OP level the meters also go up - and then I DO get a change in volume.

Theres is something more to this than a pure signal level the amp is getting - and im not sure what that is - or why its happening. When I understand how it all works together Id have a better shot but that might take a while. For Now I just need to make sure I dont blow anything yup lol - but get the gain staging and maximum levels limited.
Click to expand...
The Boost/Pad feature doesn't change the actual volume, because it's BOOSTing and PADding the signal at the same time. It boosts the signal going into the Axe's D/A converter to it can run as hot as possible, thereby reducing noise. But then it pads the signal after it's been converted back to analog. It doesn't change the final output level because it's not supposed to.
 
ok - Got an Emal from SD. the Power Stage requires a -10db input. a +4 may clip the pre-amp.

so - from OP1/2 thats easy BUT Im using OP3. Im doing this because OP2 doesnt have a jack output, and OP1 is where the "with cab block" feed is going (mainly because all the factory pre-sets use OP1 -= and I cant be bothered to add another block to audition/play with each one. I may change this down the line and go OP2 for SPdif and Op1 to the amp).

Reading the manual - it says the pad/boost should be max'd when feeding an eternal amp - but I also read (cant remember exactly where now) that OP3/4s level needs raising by 7.2?db to match -10 and 19.5 to match +4.

so - do I need to set the pad on 6db (just under the -10 level), to 18 (to max it as per the manual) or just leave it as it is?

Its all a little confusing at present.
 
paulmapp8306 said:
Reading the manual - it says the pad/boost should be max'd when feeding an eternal amp...
Click to expand...

That's not quite what it says:

To find the right setting, adjust either of these settings as high as possible without clipping the outputs, as indicated by a red LED on the front panel meters. You’ll actually hear the noise floor drop as you increase Boost/Pad.
Click to expand...
 
Use the OUT3 block meter to gauge your level going into the D/A converter.

Per the manual, max output for Output 3 is +20dBu. I would guess that should be roughly at 0dBFS, the clipping point for the D/A converter. When the output meter for OUT3 is at the 0 dB line, it's at about -12 dBFS peak at the D/A converter. That means 0 dB on that meter should give you roughly 12 dB below the max output or roughly +8 dBu analog output level when the front panel Out 3 knob is all the way up. If you want -10 dBV (about -7.78 dBu) from the output, you'll want the OUT3 block meter to read about -15.78 dB. Since the D/A level is then fairly low, you can improve your SNR by turning up the Boost/Pad to compensate. Setting it to 18 dB will then give you -10 dBV at the output when the OUT3 meter is now reading around 2.2 dB.

Judging by the amount the Output meter changes, it appears that the 18 dB Boost/Pad setting only boosts the D/A level 14 dB instead of the full 18, so aim for around -1.78 dB on the OUT3 block meter and that should give you pretty close to -10 dBV line level at the output when the Out 3 knob is up full.

To verify, I fed a synth block outputting a 60 Hz sine wave into the OUT3 block, set Boost/Pad for Output 3 to 18 dB, cranked the front panel Out 3 knob and measured the output voltage with my cheapo multimeter. I adjusted the synth block output level until I got about 0.316 volts (-10 dBV) at the output. I then checked the OUT3 block meter and it read -0.8 dB. That's within 1 dB of my estimate above. Not bad for some quick and dirty figures. My cheap meter could easily be off that much. I'd need a proper oscilloscope to measure it right.
 
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