Ampeg SGT-DI

[klattman]

This finally makes sense that buzzy sound I was hearing in the svt setting in the previous demos was the cab impulse clipping.

Impulse can section input clipping is something to watch out for. I even have that issue on the ashdown lb-2N. running a limiter to catch the peaks helps.

 

[klattman]

That's because the levels for each are set to the same level last used. So you can set each to unity gain to alleviate this difference in volume between cab sims. Set the 115 to your desired volume using the push in cab sim volume knob, then match the same volume to the 410, and finally the 810. From there the volumes will remain the same until you change each again.

that makes sense and is a nice feature. I had assumed the volume control affected them all together.

 

[LANnerd]

Impulse can section input clipping is something to watch out for. I even have that issue on the ashdown lb-2N. running a limiter to catch the peaks helps.

When proper gain staging is done, no limiters are necessary.
I'ts a bit cringing to even see the Ampeg guys having trouble getting rid of the IR loader clip light cause it's very simple.
Just turn down the output from the pre-amp(volume left on top of compressor knob). If the resulting volume is to low, turn the output of the cab loader (the little plastic button on the side) up to compensate and done, no more input clipping on the IR loader.
You can't overdrive a IR loader like a real speaker cab because it's digital and you are overdriving the A/D converter on the IR loader input.

A look at the flow chart in the back of the manual may help to understand the gain staging of the SGT. It's basically a overdrive pedal, into a compressor pedal, into a pre-amp pedal, into a Ir loader pedal, all with their own output levels knobs that can be used to prevent the next stage from clipping. the compressor works as a fail safe between the SGT overdrive pedal and the pre-amp pedal, but the output of the pre-amp to the IR-loader doesn't have that and will have to be monitored manually.

 

[Ethereal Thorn]

When proper gain staging is done, no limiters are necessary.
I'ts a bit cringing to even see the Ampeg guys having trouble getting rid of the IR loader clip light cause it's very simple.
Just turn down the output from the pre-amp(volume left on top of compressor knob). If the resulting volume is to low, turn the output of the cab loader (the little plastic button on the side) up to compensate and done, no more input clipping on the IR loader.
You can't overdrive a IR loader like a real speaker cab because it's digital and you are overdriving the A/D converter on the IR loader input.

A look at the flow chart in the back of the manual may help to understand the gain staging of the SGT. It's basically a overdrive pedal, into a compressor pedal, into a pre-amp pedal, into a Ir loader pedal, all with their own output levels knobs that can be used to prevent the next stage from clipping. the compressor works as a fail safe between the SGT overdrive pedal and the pre-amp pedal, but the output of the pre-amp to the IR-loader doesn't have that and will have to be monitored manually.

So far I've heard that clipping on every demo video so it must be pretty sensitive.

 

[LANnerd]

So far I've heard that clipping on every demo video so it must be pretty sensitive.

The fact that all the factory IR settings set the output around 50% probably won't help either. People tend to compensate by turning the pre-amp volume up with clipping as a result.

Also the EQ has a max boost of 15dB. that's a lot and can clip the Ir loader easily.

Or Ampeg messed up the internal gain staging, but will have to play around with one first to be able to comment on that. A quick turn on the knobs will probably fix that, although as you say could be sensitive.

Will have to see when these release in Europe and i can get my hands on one.

 

[Ethereal Thorn]

The fact that all the factory IR settings set the output around 50% probably won't help either. People tend to compensate by turning the pre-amp volume up with clipping as a result.

Also the EQ has a max boost of 15dB. that's a lot and can clip the Ir loader easily.

Or Ampeg messed up the internal gain staging, but will have to play around with one first to be able to comment on that. A quick turn on the knobs will probably fix that, although as you say could be sensitive.

Will have to see when these release in Europe and i can get my hands on one.

Hopefully someone here can post a demo with some of the svt settings doing edge of break up slight overdrive sounds with a pick and dial it in without the ir clipping I've been really curious how that sounds on this. I'm really impressed with the b15 sounds so far

 

[klattman]

The fact that all the factory IR settings set the output around 50% probably won't help either. People tend to compensate by turning the pre-amp volume up with clipping as a result.

Also the EQ has a max boost of 15dB. that's a lot and can clip the Ir loader easily.

Or Ampeg messed up the internal gain staging, but will have to play around with one first to be able to comment on that. A quick turn on the knobs will probably fix that, although as you say could be sensitive.

Will have to see when these release in Europe and i can get my hands on one.

Setting the IR output higher and lowering the preamp works just fine. If you want the max grit and an aggressive EQ then the comp is the last option.

this is a common problem, clipping an IR stage. Have to avoid it because clotting the digital section sounds terrible.

 

[Michael Vee]

Ampeg should include a switch-defeatable hard limiter in front of the IR section, for the V2 SGT.

 

[LANnerd]

Setting the IR output higher and lowering the preamp works just fine. If you want the max grit and an aggressive EQ then the comp is the last option.

this is a common problem, clipping an IR stage. Have to avoid it because clotting the digital section sounds terrible.

The comp is not going to fix aggressive EQing because the compressor is before the EQ in the chain, as you would usually want. Just use the level knob the way it was meant to and use the compressor for artistic purposes.

Ampeg should include a switch-defeatable hard limiter in front of the IR section, for the V2 SGT.

Or Bassplayers take a little interest in their tools and learn a little about gain staging.
Just a matter of perspective

 

[Ian774]

Setting the IR output higher and lowering the preamp works just fine. If you want the max grit and an aggressive EQ then the comp is the last option.

this is a common problem, clipping an IR stage. Have to avoid it because clotting the digital section sounds terrible.

how can one expect to lower the preamp volume and set the IR volume higher, if one wants the SGT to drive an amp’s power amp AND go to the PA via the DI?

 

[LANnerd]

how can one expect to lower the preamp volume and set the IR volume higher, if one wants the SGT to drive an amp’s power amp AND go to the PA via the DI?

Usually you'd expect that by the time the IR loader starts clipping the poweramp is shaking the room and the sound tech will politely ask you to turn it down.
Other solutions would be to:
Plug in the front of the amp and add the amps pre-amp with flat EQ and a little bit of gain.
Or when using only a power amp without gain knob add a clean boost pedal in between.

But i can't imagine it being an issue unless Ampeg really messed up.

 

[klattman]

The comp is not going to fix aggressive EQing because the compressor is before the EQ in the chain, as you would usually want. Just use the level knob the way it was meant to and use the compressor for artistic purposes.

the comp still catches the peaks from the bass. So it does help even before everything else. By aggressive EQ I mean you’ve boosted something and cut something else so you can’t compensate with levels. If you are boosting everything so playing with a medium hand still clips then I think you are stuck.

My tube amps and this pedal sound best when I want to push the power section (or emulation of a power section). Makes it hard to deal with the cabsim.

I’d use a different compressor if I wanted it to be artistic. The one onboard is useful but meh.

 

[klattman]

Usually you'd expect that by the time the IR loader starts clipping the poweramp is shaking the room and the sound tech will politely ask you to turn it down.
Other solutions would be to:
Plug in the front of the amp and add the amps pre-amp with flat EQ and a little bit of gain.
Or when using only a power amp without gain knob add a clean boost pedal in between.

But i can't imagine it being an issue unless Ampeg really messed up.

I’ve not had to lower the preamp so much that it can’t drive my rig, but I have a ton of power there to work with.

 

[Michael Vee]

Or Bassplayers take a little interest in their tools and learn a little about gain staging.Just a matter of perspective

Or people who post on Talkbass have some respect for differing opinions. There are many audio engineers who hard-limit in front of digital processing to prevent overloads. It's a common practice.

 

[LANnerd]

the comp still catches the peaks from the bass. So it does help even before everything else. By aggressive EQ I mean you’ve boosted something and cut something else so you can’t compensate with levels. If you are boosting everything so playing with a medium hand still clips then I think you are stuck.

My tube amps and this pedal sound best when I want to push the power section (or emulation of a power section). Makes it hard to deal with the cabsim.

I’d use a different compressor if I wanted it to be artistic. The one onboard is useful but meh.

You're always going to be able to turn the level knob down so i don't get why there would be an issue.
The emulation of tubes is in the SGT circuit, which sits in front of everything else so the only way to push that is to increase the gain knob.
This isnt a tube amp, its using low voltage circuitry to emulate it.

 

[LANnerd]

Or people who post on Talkbass have some respect for differing opinions. There are many audio engineers who hard-limit in front of digital processing to prevent overloads. It's a common practice.

I've worked in pro audio for years and have always used limiters as safety devices to prevent hearing and speaker damage(for example when musicians are dropping mics and unplugging jacks when not muted).
Needing limiters to prevent clipping is just bad gain staging and detrimental to the sound and thus frowned upon in the pro audio community.

I'm not saying you're wrong in wanting to do you(use a limiter). I'm just saying there are other opinions and ways of doing it and demanding ampeg adds a limiter is maybe not the fastest way to achieve your goal.

 

[Akiyama]

I have a SGT-DI on order from GC.

Mainly because of Bass the World's nice demo/review (No affiliation) and TBers' comments made the decision a no-brainer.



Ampeg is love. Ampeg is life.

 

[klattman]

I was highly skeptical because I hated the SCR, but they did a great job on the SGT.

would have been nice to have an effects loop and an adjustable hpf for the preamp, but if one device had everything, how could they get you to buy the next one?

 

[JeezyMcNuggles]

So far I've heard that clipping on every demo video so it must be pretty sensitive.

It is

 

[JeezyMcNuggles]

Hopefully someone here can post a demo with some of the svt settings doing edge of break up slight overdrive sounds with a pick and dial it in without the ir clipping I've been really curious how that sounds on this. I'm really impressed with the b15 sounds so far

There isn't any "edge of break up"

It's either a drive pedal, or a ss portaflex pre amp.