Use power amp for attenuator

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peterc52

peterc52

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Do I need a Suhr ISO box for slaving into my VHT 2150 and use it for attenuation?

Much better taper on that volume control.

My rectifier has a slave out and it’s much better to adjust volume on the VHT

Or?
 
I think to essentially mute the Recto's power amp, you need some type of load box (either with the ISO box or with its own line out). With just the ISO box, the Recto will still need to be plugged into a cab.
 
cardinal said:
I think to essentially mute the Recto's power amp, you need some type of load box (either with the ISO box or with its own line out). With just the ISO box, the Recto will still need to be plugged into a cab.
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I use a THD Hotplate for load box. But how do I use the power amp with my JMP 2203?
 
Speaker out of the JMP to the Hot Plate set to LOAD. Hot Plate line out to power amp input. Power amp connected to speakers.

You might get better results not using the poweramp. Hot Plate connected to speakers and set to -16dB's.
 
peterc52 said:
something like a suhr iso box wont work?
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Send one speaker out to the Hot Plate as a load box (match the amp impedance to the Hot Plate). Then, use either 1) Hot Plate's line out (think it has one?) or 2) another speaker out to the ISO box. Send the cable from either 1 or 2 to the input of your power amp. Plug the power amp into your speaker cab.
 
I've often wondered while reamping if there's any difference in tone between using a Suhr Iso box vs using the line out of the Suhr Reactive Load's line out?
The Iso box uses a transformer I believe.
 
The ISO box has no load.

If you want something with a load from Suhr, you need the Suhr Reactive Load.

The ISO box just takes signal from a speaker out and lets you send it to a mixer or another power amp etc. The amp needs a load from somewhere else.
 
cardinal said:
The ISO box has no load.

If you want something with a load from Suhr, you need the Suhr Reactive Load.

The ISO box just takes signal from a speaker out and lets you send it to a mixer or another power amp etc. The amp needs a load from somewhere else.
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You misunderstood my question (or I didn't phrase it clearly). I've wondered if there's any difference in tone running the line out from the Suhr Reactive Load into a power amp vs taking a line out from the Suhr Iso box (while still having the amp plugged into the Suhr RL) and running it into the power amp instead.
 
chumbucket said:
You misunderstood my question (or I didn't phrase it clearly). I've wondered if there's any difference in tone running the line out from the Suhr Reactive Load into a power amp vs taking a line out from the Suhr Iso box (while still having the amp plugged into the Suhr RL) and running it into the power amp instead.
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I imagine the Suhr reactive Load line out is optimized for IR levels, I don't know if it is the same as a regular line level to drive a power amp input. According to Suhr it should work the same as the Iso Lineout as well as feed IR's.

Suhr Reactive Load Box 8 ohms 100 RMS Max Di Direct Box For Guitar Amplifier

The Suhr Reactive Load delivers a simple solution to capture all of the warmth, and dynamics of your sound, without the hassle of miking a speaker cabinet during a live or recorded performance.

The Reactive Load takes the place of your speaker cabinet in your signal chain. It provides an 8Ω load for your tube amplifier (maximum 100 watts), and produces a balanced and unbalanced signal that interfaces with recording devices, effects, and power amplifiers.

INTERFACE TO YOUR IRs

The Suhr Reactive Load is the perfect link between your amplifier and computer audio recording interface. You can use the Reactive Load with your existing library of speaker impulse responses (IR) for the most realistic direct recording experience possible.
 
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peterc52 said:
Do I need a Suhr ISO box for slaving into my VHT 2150 and use it for attenuation?

Much better taper on that volume control.

My rectifier has a slave out and it’s much better to adjust volume on the VHT

Or?
Click to expand...
I am going to assume you already know how to use the THD hotplate for a load for your Dual Rectifier.

I think the line out for the rectifier is preamp signals only and not the full preamp power amp signals as coming from the speaker jacks of the Dual Recitifier. I am not 100% certain of this but I think Mesa used the preamp slave out to drive the power amp sections of other Dual Rectifier's for live performances. The Mesa slave out may work just fine but you will need to confirm it it has just the preamp signal or preamp and power amp signals.

Since you are slaving and want the entire preamp power amp signals reamplified by your VHT power amp then it would sound best if you used the line out from the THD or get a Suhr Iso Line Out to tap the entire preamp/power amp signal at the other avialable speaker jack of the Dual Recto.

The THD line out has both the entire preamp/power amp signals and an adjustable level control so oyu can set how hard it hit the power amps input and will work just fine for you. I have used my THD lineout for slaving but when compared to my Suhr Iso Lineout I find the Suhr sounds better for a more accurate reproduction.

Bottom line is the THD lineout works, sounds fine and it might be good enough for you.
 
peterc52 said:
I use a THD Hotplate for load box. But how do I use the power amp with my JMP 2203?
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You do the same with your 2203. You will run your 2203 speaker cable into the INPUT FROM AMPLIFIER jack of the THD hotplate set to load then use the THD lineout to feed your VHT power amp input. The THD has a line out level knob to control how hot of a signal you want to set hitting the input of your VHT power amp
 
Soundstorm said:
You’d have to have an FX loop installed
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No, just a line out box will do just fine. You can get one from Bray for 50$. I use one with my JMPs. The Suhr version has an ISO transformer, and is more $$. Since he has a hot plate for the load, just a simple line out box is all he needs. Or, use the hot plate only. Either will work without cutting the amp up for a tone sucking loop.
 
Racerxrated said:
No, just a line out box will do just fine. You can get one from Bray for 50$. I use one with my JMPs. The Suhr version has an ISO transformer, and is more $$. Since he has a hot plate for the load, just a simple line out box is all he needs. Or, use the hot plate only. Either will work without cutting the amp up for a tone sucking loop.
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Yeah my mistake, I thought he was asking how to run INTO the power amp of his JMP.
 
harddriver said:
I am going to assume you already know how to use the THD hotplate for a load for your Dual Rectifier.

I think the line out for the rectifier is preamp signals only and not the full preamp power amp signals as coming from the speaker jacks of the Dual Recitifier. I am not 100% certain of this but I think Mesa used the preamp slave out to drive the power amp sections of other Dual Rectifier's for live performances. The Mesa slave out may work just fine but you will need to confirm it it has just the preamp signal or preamp and power amp signals.

Since you are slaving and want the entire preamp power amp signals reamplified by your VHT power amp then it would sound best if you used the line out from the THD or get a Suhr Iso Line Out to tap the entire preamp/power amp signal at the other avialable speaker jack of the Dual Recto.

The THD line out has both the entire preamp/power amp signals and an adjustable level control so oyu can set how hard it hit the power amps input and will work just fine for you. I have used my THD lineout for slaving but when compared to my Suhr Iso Lineout I find the Suhr sounds better for a more accurate reproduction.

Bottom line is the THD lineout works, sounds fine and it might be good enough for you.
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The 2 channel Rectos I know, the slave line out comes off the output transformer.
 
3ch recto slave out is all off the output transformer, when I use my recto I usually run it into a reactive load then run the slave out to my axe FX for effects (then into a solidstate poweramp and cab).

The recto, especially in modern mode, I think sounds awful with my hotplate. A quality load like the suhr is much better sounding. Though if you’re running the slave out into a tube power amp maybe it’s less noticeable.
 
mnemonic said:
3ch recto slave out is all off the output transformer, when I use my recto I usually run it into a reactive load then run the slave out to my axe FX for effects (then into a solidstate poweramp and cab).

The recto, especially in modern mode, I think sounds awful with my hotplate. A quality load like the suhr is much better sounding. Though if you’re running the slave out into a tube power amp maybe it’s less noticeable.
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Did you ever compare to see if you notice the dynamics change by running directly through your Axe II? I know we were talking about that in a thread awhile back.
 
Shask said:
Did you ever compare to see if you notice the dynamics change by running directly through your Axe II? I know we were talking about that in a thread awhile back.
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I actually forgot about that, I did recently compare running direct into cab vs load > axe FX > SS power amp > cab, and volume-matched it sounded/felt the same enough to me, but that also took like a minute to move cables around and that’s enough time that it’s hard to really a/b.
 
Shask said:
The 2 channel Rectos I know, the slave line out comes off the output transformer.
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If that's the case then the Slave out should be preamp and power amp just as if it is being tapped at the speaker jacks.....Yes???????????
 
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