low to high impedance for reamping - help

Nick13

Looking for some pointers.  I want to use my helix rack to reamp using a real amp so I'd be sending the recorded di to one of the send jacks on the rear and then hooking that up to an amp.

I understand that the helix instrument send is low impedance so I need to convert this to high before it hits the amp.

I don't seem to be able to find a product that is designed to do this that just takes an instrument cable input on one end and then sends a high impedance signal out an instrument cable jack at the other.

Anyone got any ideas?

Would i be better switching the output to line level and then using a reamp box to convert it?

springhead

I don’t see your problem. Just plug the Helix send into the amp. A guitar pedal is a low impedance output too, no problem with a low output impedance feeding a high input impedance. It’s the right way round to avoid signal loss/hf rolloff. Are you worried it’ll sound different to a guitar plugged directly into the amp? 

Nick13

springhead said:

I don’t see your problem. Just plug the Helix send into the amp. A guitar pedal is a low impedance output too, no problem with a low output impedance feeding a high input impedance. It’s the right way round to avoid signal loss/hf rolloff. Are you worried it’ll sound different to a guitar plugged directly into the amp? 

I know it does unfortunately, when im reamping the tracked di it sounds awful coming out the amp, boxy sort of square wave almost.

Signal chain is:

Guitar Di routed to helix send set to instrument level

Send into amp

Amp into fryette ps2a

Ps2a back into helix xlr mic input

Track off this mic input

When I do this it's horrible sounding

When I plug the guitar that tracked the di directly into the amp and use the rest of the signal chain as stated above it sounds great.

So there's something not right.

I was advised by someone on the l6 forum that it's an impedance mismatch as the helix sends low impedance instrument signal and the amp wants to see high impedance input.

Seems to be very little info on using helix rack this way which I'm quite surprised about. I can't be the first person to try this.

octatonic

Nick13 said:

Looking for some pointers.  I want to use my helix rack to reamp using a real amp so I'd be sending the recorded di to one of the send jacks on the rear and then hooking that up to an amp.

I understand that the helix instrument send is low impedance so I need to convert this to high before it hits the amp.

I don't seem to be able to find a product that is designed to do this that just takes an instrument cable input on one end and then sends a high impedance signal out an instrument cable jack at the other.

Anyone got any ideas?

Would i be better switching the output to line level and then using a reamp box to convert it?

I don't have a Helix but if you can send line level into the Radial X Amp it will output at the appropriate level to input into the amp.

https://www.radialeng.com/product/x-amp

Everything Radial makes is top notch.

Nick13

octatonic said:

Nick13 said:

Looking for some pointers.  I want to use my helix rack to reamp using a real amp so I'd be sending the recorded di to one of the send jacks on the rear and then hooking that up to an amp.

I understand that the helix instrument send is low impedance so I need to convert this to high before it hits the amp.

I don't seem to be able to find a product that is designed to do this that just takes an instrument cable input on one end and then sends a high impedance signal out an instrument cable jack at the other.

Anyone got any ideas?

Would i be better switching the output to line level and then using a reamp box to convert it?

I don't have a Helix but if you can send line level into the Radial X Amp it will output at the appropriate level to input into the amp.

https://www.radialeng.com/product/x-amp

Everything Radial makes is top notch.

Hilariously I have just sold one of these as I thought the helix could do the whole job based on the fact it could send at instrument level, I thought this negated the requirement for a reamp box but does not seem so!

steamabacus

There's the Orchid Electronics Amp Interface. UK made, quality should be as high as their DI boxes, isolaters, etc which are generally very well thought of (I use a couple of their isolaters myself).

Sales now handled through Showbitz ...

https://www.showbitz.co.uk/product/amp-interface/

steamabacus

If you're handy with a soldering iron, Guitar & Bass Magazine published a DIY Re-amp box project in their 'Tranny Tricks' Transistor Workshop article a few years ago. Here's a scan of the relevant part ...

The parts list is on this page here ...

Nick13

steamabacus said:

If you're handy with a soldering iron, Guitar & Bass Magazine published a DIY Re-amp box project in their 'Tranny Tricks' Transistor Workshop article a few years ago. Here's a scan of the relevant part ...

The parts list is on this page here ...

Cheers, I am most certainly not though

Danny1969

Nick13 said:

springhead said:

I don’t see your problem. Just plug the Helix send into the amp. A guitar pedal is a low impedance output too, no problem with a low output impedance feeding a high input impedance. It’s the right way round to avoid signal loss/hf rolloff. Are you worried it’ll sound different to a guitar plugged directly into the amp? 

I know it does unfortunately, when im reamping the tracked di it sounds awful coming out the amp, boxy sort of square wave almost.

Signal chain is:

Guitar Di routed to helix send set to instrument level

Send into amp

Amp into fryette ps2a

Ps2a back into helix xlr mic input

Track off this mic input

When I do this it's horrible sounding

When I plug the guitar that tracked the di directly into the amp and use the rest of the signal chain as stated above it sounds great.

So there's something not right.

I was advised by someone on the l6 forum that it's an impedance mismatch as the helix sends low impedance instrument signal and the amp wants to see high impedance input.

Seems to be very little info on using helix rack this way which I'm quite surprised about. I can't be the first person to try this.

I think you are just hitting the input of the amp too hard. Use something to pad the level down, like a simple volume control in a box. 
I have re amped loads of stuff and never used any dedicated re amp boxes. Normally I re amp straight from the audio interface and just pad the level down to roughly what it would be from a guitar. 

Another trick I use is to record the send out of a amp with the output of the amp muted to get a good take at low volume .. into the audio interface with a speaker sim on the track. Then when the takes good remove the speaker sim and send that audio back into the return socket of the amp .. mic it up and record it back in a decent level. 
This give you a great amp sound but you only need to record at volume for the duration of the track, not for endless takes 

Nick13

Danny1969 said:

Nick13 said:

springhead said:

I don’t see your problem. Just plug the Helix send into the amp. A guitar pedal is a low impedance output too, no problem with a low output impedance feeding a high input impedance. It’s the right way round to avoid signal loss/hf rolloff. Are you worried it’ll sound different to a guitar plugged directly into the amp? 

I know it does unfortunately, when im reamping the tracked di it sounds awful coming out the amp, boxy sort of square wave almost.

Signal chain is:

Guitar Di routed to helix send set to instrument level

Send into amp

Amp into fryette ps2a

Ps2a back into helix xlr mic input

Track off this mic input

When I do this it's horrible sounding

When I plug the guitar that tracked the di directly into the amp and use the rest of the signal chain as stated above it sounds great.

So there's something not right.

I was advised by someone on the l6 forum that it's an impedance mismatch as the helix sends low impedance instrument signal and the amp wants to see high impedance input.

Seems to be very little info on using helix rack this way which I'm quite surprised about. I can't be the first person to try this.

I think you are just hitting the input of the amp too hard. Use something to pad the level down, like a simple volume control in a box. 
I have re amped loads of stuff and never used any dedicated re amp boxes. Normally I re amp straight from the audio interface and just pad the level down to roughly what it would be from a guitar. 

Another trick I use is to record the send out of a amp with the output of the amp muted to get a good take at low volume .. into the audio interface with a speaker sim on the track. Then when the takes good remove the speaker sim and send that audio back into the return socket of the amp .. mic it up and record it back in a decent level. 
This give you a great amp sound but you only need to record at volume for the duration of the track, not for endless takes 

Yeah seems that is likely what it is.  ill get something to put between the helix output and the amp like another radial reamp box or something.

Musicwolf

Nick13 said:

Yeah seems that is likely what it is.  ill get something to put between the helix output and the amp like another radial reamp box or something.

Start my turning down the output of the Helix.  You could put a gain block in the signal path and attenuate it that way.

springhead

It has to be level related. Hence my post earlier. If you ever use that amp with a pedal in front of it then you’re driving it from a low impedance. Varies from one pedal to another but apart from old fuzz pedals etc it’ll be a low impedance. Should be no different to driving it from the Helix. 

Nick13

Yeah I think it is, ill try the gain block in that pathway, neverthought of that!

Nick13

Tried that, also does not work.  Using a volume or gain block went from this (video of the issue below) to nothing with very little in between.

https://www.amazon.co.uk/photos/share/IT66clHHPR47W3LUVugJ9Dqb7hHI2COlAXzcmPPzcLG

Reckon ill just try it with the reamp box once I source another one and hopefully sending out at line level via xlr to that will work fine.

Appreciate the points about the impedance should not be an issue but the line 6 forum says this is THE issue so I have tried one way, I will try another.

Nick13

Yeah so got the reamp box  - radial jcr and the issue persists! I am pretty confused.

Musicwolf

Apolgies if you've already checked this, but..........

You have checked that the initial DI recording isn't clipped / distorted haven't you?

Nick13

Musicwolf said:

Apolgies if you've already checked this, but..........

You have checked that the initial DI recording isn't clipped / distorted haven't you?

Yeah its not, the di works fine for usb only reamping via the helix.  there is obviously some sort of gain staging issue coming out of the helix into the analogue gear which i can't seem to work out how to fix.