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Double Bass Preamp recommendations for Realist
- Thread starter bilias
- Start date
I have the BrightEye, which had the same impedance matching feature as the RedEye. I used it on a gig once with the D4 when i forgot my Headway and was not able to get the same level of usable volume. The D4 was farting out, and so I really missed having the HPF.
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Okay...that tracks...but then the "Vol" knob on a pre-amp is input volume. What would contitiute "gain" in something (like a pedal) in front of the amp?
I don't get it. I don't need to get it, I guess.
I just googled this and read 8-10 answers. Sources ranged from Reddit threads, to manufacturers websites (Fender, Carvin) to recording industry articles. Consistently, they say, sometimes using different words, that gain and volume (knobs) are technically the same thing. The term "gain" is typically used when it's applied before the pre-amp and "volume" after. Here's the clearest of the quotes:
"There is really only one difference between gain and volume and that's when the occur in the signal chain. Gain comes first. It controls the input level in a chain. Volume comes last. It controls the output level."
I always assume in these discussions that I'm wrong, becuse there is a lot that I don't understand once electricity gets involved, but unless someone can dispute this and site sources, I don't think I am in this case.
Any box that sits in front of the input on an amp, including a powered speaker, is...if we want to be pedantic about it, "gain". Even if it's labeled "Volume", because they are not different things.
Technically, maybe, if you plugged it into the effects return...maybe it becomes volume since you bypassed the pre-amp, but I'm not sure anymore and it doesn't matter because they are not really different things. Regardless, it would be the same with both devices despite how they were labeled.
Am I wrong? Still allowing for the possibility, but reading doesn't support that. What would make a knob on one pre-amp "gain" and the equivalent knob on another one "volume" used in the same context?
"There is really only one difference between gain and volume and that's when the occur in the signal chain. Gain comes first. It controls the input level in a chain. Volume comes last. It controls the output level."
I always assume in these discussions that I'm wrong, becuse there is a lot that I don't understand once electricity gets involved, but unless someone can dispute this and site sources, I don't think I am in this case.
Any box that sits in front of the input on an amp, including a powered speaker, is...if we want to be pedantic about it, "gain". Even if it's labeled "Volume", because they are not different things.
Technically, maybe, if you plugged it into the effects return...maybe it becomes volume since you bypassed the pre-amp, but I'm not sure anymore and it doesn't matter because they are not really different things. Regardless, it would be the same with both devices despite how they were labeled.
Am I wrong? Still allowing for the possibility, but reading doesn't support that. What would make a knob on one pre-amp "gain" and the equivalent knob on another one "volume" used in the same context?
The HPFpre (Vers. 1 and 2) has 2 or 3 dB of gain which is not much indeed.
The volume control can reduce the 2-3 dB amplification to a lower level, but not raise it.
You have three options:
1. Get a different amp
2. Get a preamp with voltage amplification of at least 12 dB
3. Get a different pickup (and maybe a preamp too)
Maybe
4. Ask for a modification of the amp for a higher input sensitivity (and higher input impedance)
Good luck!
The volume control can reduce the 2-3 dB amplification to a lower level, but not raise it.
You have three options:
1. Get a different amp
2. Get a preamp with voltage amplification of at least 12 dB
3. Get a different pickup (and maybe a preamp too)
Maybe
4. Ask for a modification of the amp for a higher input sensitivity (and higher input impedance)
Good luck!
Gain sits in front of the EQ, volume after EQ and effect loop. It is defined for one device, so a preamp can have its own gain and volume. Older or simpler amps often do not have a gain control, so the gain is fixed.
Gain often sits as a kind of early stage volume control behind the first amplification stage. This means that a high input signal can distort the first amplifier stage (often JFET or valve for a high impedance) and turning the gain down is too late in the signal chain to avoid that. In this case a passive damper circuit is needed in front of the amp (like the capacitor for a Yamahiko or Full Circle). High resistance pots are mostly limited to 5 MegOhms and rather sensitive to corrosion, so the high impedance amplification stage is located in front of the gain control.
This also has less influence depending on the impedance of the source.
Gain often sits as a kind of early stage volume control behind the first amplification stage. This means that a high input signal can distort the first amplifier stage (often JFET or valve for a high impedance) and turning the gain down is too late in the signal chain to avoid that. In this case a passive damper circuit is needed in front of the amp (like the capacitor for a Yamahiko or Full Circle). High resistance pots are mostly limited to 5 MegOhms and rather sensitive to corrosion, so the high impedance amplification stage is located in front of the gain control.
This also has less influence depending on the impedance of the source.
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Okay, maybe I almost understand, thank you for your patience with me. So, the Headway is essentially an amplifier? If you put it into a passive cabinet, you would have volume (assuming, not a significant amount)?
The Fdeck HPF is a unity gain device. Unity gain means that with the volume wide open, the output level is the same as the input level. The volume is essentially an attenuator; it can cut down the signal but it can't turn it up.
However, something we may be missing, the signal strength a piezo can produce is impacted by the input impedance of the amp. Plugging a piezo into a device with low input impedance will load down the pickup resulting in a weak signal. The Fdeck will buffer the signal so it's not being loaded down. So in this instance, using the Fdeck should actually result in a stronger signal reaching the amp.
Not sure what the issue is with the Double Four. Per the OM the input impedance of the High input is 1Meg and the input impedance of the Low input is 30K. For a piezo the 1Meg input should work. It's sort of the minimum acceptable load. Per the OM, sensitivity for the high input is 30mV which AFAIK is about -28dBu. -28dBu is a pretty weak signal, so I am surprised a Realist buffered by an Fdeck HPF doesn't work.
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I have a PJB C2 cab, Warwick Gnome amp and a Realist lifeline pickup. I've started using an FDeck and it does a good job of calming down any boominess and generally fine tuning the sound. This is the one that I have:
https://reverb.com/uk/item/13880879...le-high-pass-filter-phase-switch-custom-color
It depends on the pickup how strong/loadable (impedancewise) and how high the voltage swing is.
Piezo disks are often used in acetone way as they are mainly bending sensitive and hardly pressure sensitive. Also the thin piezoceramic wafer on the brass needs a high input impedance like 10 MegOhms.
A preamp that can amplify the voltage by 20 dB or more would be indeed safer to solve a quiet amp output, but a frequency controllable high pass filter can get most out of a low wattage/small speakers amp by removing unneeded frequencies and boost the rest higher with the wattage freed by the low stuff.
But these preamps are a lot more expensive than a HPFpre.
Maybe you can fetch used earlier Headway for a reasonable price.
Piezo disks are often used in acetone way as they are mainly bending sensitive and hardly pressure sensitive. Also the thin piezoceramic wafer on the brass needs a high input impedance like 10 MegOhms.
A preamp that can amplify the voltage by 20 dB or more would be indeed safer to solve a quiet amp output, but a frequency controllable high pass filter can get most out of a low wattage/small speakers amp by removing unneeded frequencies and boost the rest higher with the wattage freed by the low stuff.
But these preamps are a lot more expensive than a HPFpre.
Maybe you can fetch used earlier Headway for a reasonable price.
Earl
Supporting Member
Earlier D Fours, like mine are only 500k from the High input.
I hope OP is finding this thread helpful, but it may be more confusing and rambling than helpful. Here is a list of recommendations i can think of that include adjustable HPF, high input impedance, and signal boosting, and are small and affordable(ish):
Fishman platinum stage
Headway EDM 1 (HE is the current version, non HE can still be found used for less)
LR Baggs Gigpro (i think it’s discontinued but can be found used. Very small, great battery life. it also has a dual channel version called the Mixpro)
Some of the ART tube preamps have switchable HPFs and can make nice preamps.
There are also old Fishman Platinum Bass preamps still readily found used, but they’re quite old now and may not be the most reliable at this point.
Many bassists have used the Tech 21 Bass Driver and Paradriver with success, but there’s no adjustable HPF on these.
I think the Zoom MS 60B could technically fulfill these functions ( might have to use the parametric EQ for HPF).
The Zoom A3 would also work and provide a zillion other functions as well.
Radial Bassbones are pretty common as piezo preamps as well. Some versions have an HPF with a couple of settings.
I think the platinum stage would be an awfully solid choice and could likely be found used for 100ish.
Fishman platinum stage
Headway EDM 1 (HE is the current version, non HE can still be found used for less)
LR Baggs Gigpro (i think it’s discontinued but can be found used. Very small, great battery life. it also has a dual channel version called the Mixpro)
Some of the ART tube preamps have switchable HPFs and can make nice preamps.
There are also old Fishman Platinum Bass preamps still readily found used, but they’re quite old now and may not be the most reliable at this point.
Many bassists have used the Tech 21 Bass Driver and Paradriver with success, but there’s no adjustable HPF on these.
I think the Zoom MS 60B could technically fulfill these functions ( might have to use the parametric EQ for HPF).
The Zoom A3 would also work and provide a zillion other functions as well.
Radial Bassbones are pretty common as piezo preamps as well. Some versions have an HPF with a couple of settings.
I think the platinum stage would be an awfully solid choice and could likely be found used for 100ish.
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As Lovely as the FDeck HPF buffer preamps are ( at one time I owned all three different models) Francis clearly stated that they were designed to provide a small amount of gain to compensate for their insertion into the signal chain. Their true value lies in their ability to smoothly cut low end response and provide a higher impedance load. The box improves the two most common issues with piezo pickups. To much bass response and to much quack. Just my take
The Headway as Povi states is a pre amplifier with every bell and whistle most of us would ever need to EQ a Double Bass. Personally, I’ve never really liked the idea of two preamps (one in front of the other) driving the power amp section of an amplifier. To me it’s overkill (we do it all the time with the active bass guitars, but that’s a horse of a different color, because they’re less susceptible to feed back ) That’s why I love the RedEye twin. It’s a preamp for sure but not as complicated. just my take however.
Did an outdoor park gig today with the great Mike Clark on drums, electric keys, horns and vocals. Used my ply bass strung with guts and a Copperhead Realist into my RedEye into my Double 4. Plenty of volume and a great sound. My Double 4 is the older version. Sure, with a 75 watt amp with 2 four inch speakers it's not gonna handle a bashing gig without farting, but the size/sound thing is wonderful.
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