RPM or RBI With Poweramp

[Growly Lytes]

Is there any bassists here that use the Tech21 RPM or RBI to run their Poweramp ?
The question is about sensitivity, what do you set the amp Sensitivity at ? The RPM puts out 1.0v. The amp i use has 3 settings 0.7v, 1.0v, 1.4v so what would give the best results using this actaul Preamp or a Preamp with 1.0v sensitivity?
The RPM & RBI both are @ 1.0v they put out the same volts.
Please Help

[Fuzzbass]

My guess would be 1.0, but I don't know. Here's a bump for your question.

[Bob Lee (QSC)]

What's the maximum output of the RPM and RBI?

[Fuzzbass]

Does this answer your question, Bob? I'm pretty sure the RPM is the same.

Model Number: RBI
Input Impedance-Input 1: 1M
Input Impedance-Input 2: 1M
Output Impedance-1/4”: 1K Ohm min
Output Impedance-XLR: 600 Ohm min
Input Level-Input 1: 1V RMS max
Input Level-Input 2: 1V RMS or 10V max, with -20dB pad engaged
Output Level-XLR: Switchable to -20dB or 0dB range
Maximum Output Level: +10dB or better
Effects Loop Send: 1K Ohm min, -20dB
Effects Loop Return: 100K Ohm min, -20dB
Low Frequency Response: 10Hz or better*
High Frequency Response: Harmonic content, 20kHz or better*
Maximum Power Consumption: 5 Watts
AC Input Power (factory set): 100V, 117V, 220V, 230V, 240V
Cycles: 50/60 Hz
NOTE: Each unit is constructed for specific
voltages. AC power cannot be switched.
Enclosure: Aluminum and steel, fully shielded
Dimensions: 19.0”w x 1.75”h x 5.25”d / Overall depth: 6.25”
Weight: 5 lbs.

[Bob Lee (QSC)]

It says the maximum output level is +10 dB or better, which would actually make sense if they also indicated what the reference level was.

Here are two likely meanings:
If they actually mean +10 dBu, then that would translate to "2.45 V or greater"
If they actually mean +10 dBV, then that would translate to "3.16 V or greater"

Either way, it's higher than any of the amp's input sensitivity settings, so you can choose any of them. There's a 3 dB gain difference in each step from 0.7V to 1V to 1.4V.

[Boostedrex]

Bob, if it's higher than the amp input settings does that mean that you could drive the input stage on the power amp into clipping? Or am I misunderstanding your post? Thank you in advance.

Zach

[Bob Lee (QSC)]

It means it could be capable of driving the output stage into clipping. That's what an amp's "input sensitivity" voltage spec means.

I doubt that it would drive the input stage into clipping, but I have no idea what power amp you have or at what input voltage it would clip.

[Growly Lytes]

O.k thanks guys but im still left asking the same question,
What should the amp be set to for the RPM to really give it a push ? I know theres heaps of factors but the main would be with the Sansamp should it match the amp or is it better to have the amp at a lower sensitivity ? Every cab is going to put its 2 cents worth so a rough guess is good enough.
Should i set my amp on the lower setting of .7v because the RPM is 1.0v ?
If i set it at 1.4v would the RPM be working harder ? If so that would mean its better to have it set to 0.7v so the Preamp doesnt have to be pushed so much?
What about when its set to 1.0v matching the RPM is this good ?
Im lost cause i cant find any info & if i do its not helping much.

[Implosion]

Try all options? You won't damage anything.

[Bob Lee (QSC)]

Originally Posted by Growly Lytes

O.k thanks guys but im still left asking the same question,
What should the amp be set to for the RPM to really give it a push ? I know theres heaps of factors but the main would be with the Sansamp should it match the amp or is it better to have the amp at a lower sensitivity ? Every cab is going to put its 2 cents worth so a rough guess is good enough.
Should i set my amp on the lower setting of .7v because the RPM is 1.0v ?
If i set it at 1.4v would the RPM be working harder ? If so that would mean its better to have it set to 0.7v so the Preamp doesnt have to be pushed so much?
What about when its set to 1.0v matching the RPM is this good ?
Im lost cause i cant find any info & if i do its not helping much.

RPM or RBI With Poweramp

You're agonizing over something that doesn't matter. Choose one and adjust the knobs; that's what they're there for. Don't worry about non-issues like the preamp being "pushed" or matching a number in one place with a number somewhere else.

[Fuzzbass]

What Bob said. Pick a setting and run with it. They're all good.

[Boostedrex]

Originally Posted by Bob Lee (QSC)

It means it could be capable of driving the output stage into clipping. That's what an amp's "input sensitivity" voltage spec means.

I doubt that it would drive the input stage into clipping, but I have no idea what power amp you have or at what input voltage it would clip.

Perfect. Thank you for the info Bob. I figured that I was off/over thinking the whole thing.

Cheers,

Zach

[Mo'Phat]

For what it's worth...I ran an RBI through QSC and Carvin amps to great success for a long time.

I never once thought about what you're obsessing about.

[Growly Lytes]

Thanks
i guess il just go with whatever works.
G.L

[alangoldstein]

rpm i hear is better

[alangoldstein]

buy both return one. or just get the all new vt bass deluxe pedal. it smokes!!! has a di too where as the vt bass didnt.

[johnk_10]

i used my RPM with a crown xti2000 that has a 1.4V input sensitivity and the RPM had way more than enough output to drive it. i had to turn the rpm's output level down to about 50% or less so i wouldn't overdrive the xti's front end. so yes, any input sensitivity setting will work with an RPM.

[Growly Lytes]

Thanks dude thats all i was really after....an insight to what other bassists set their amps sensitivity with the RPM or RBI.
Thank you all,
Keep Rockin

[Fuzzbass]

Originally Posted by alangoldstein

rpm i hear is better

Well, it's like saying "what's better, a P-bass or a J-bass?" I own both the RBI and RPM, and like 'em both so much that I use them together. If I had to pick just one I'd go with the RBI, but some prefer the RPM.

[rpsands]

The RBI needs too much gain to drive the less sensitive power amps in my experience (e.g. yamaha p2500s type). Just my two pence though. I don't like the gain sound on that pre much so I am pretty sensitive to it.