Double Bass Ehrlund "Sweet Spot", anyone?

[Ric Vice]

Thank you! Interesting! So just to clarify: the Ehrlund preamp has two settings, low and high. It's unclear how much the low setting boosts the signal, right? And the high setting boosts the signal by 7.3dB above whatever the low boost is, right? It would be helpful to know what that low number is to get a sense of the true amount boosted on high in order to duplicate the scenario with a third-party preamp like Headway.

Ukiah Bass,
Since I’ve own both the EDB-2 and the Ehrlund Preamp, I can tell you that the boost from the EAP Preamp is substantial but the EBD-2 feels like it boost the signal more. I sent a email to Ehrlund to ask specifically what the number is. I have had several conversations with Göran Ehrlund in the past so I expect we’ll know soon.

 

[N. Kentucky Bass]

Ukiah Bass,
Since I’ve own both the EDB-2 and the Ehrlund Preamp, I can tell you that the boost from the EAP Preamp is substantial but the EBD-2 feels like it boost the signal more. I sent a email to Ehrlund to ask specifically what the number is. I have had several conversations with Göran Ehrlund in the past so I expect we’ll know soon.

thanks. This morning I messaged him too with the same question. Understanding what the pickup requires will help with better gain staging the signal chain — especially for tracking.

 

[Timm]

The Ehrlund manual provides zero information on the preamp's signal boost in dB's. Such an odd omission!

I tried to measure the gain some time ago. Not very scientific so don't take the numbers to serious.
In "low" I measured 9dB of gain, and in "high" 15dB.

 

[N. Kentucky Bass]

thanks. This morning I messaged him too with the same question. Understanding what the pickup requires will help with better gain staging the signal chain — especially for tracking.

So here is my email posing the question:

I have an EAP pickup for my double bass. I was wondering about the Ehrlund Preamp for this pickup. What is the preamp's range of signal boost provided in dBs? I didn't find this information on your website. Thank you.​

And here is the response from Lars:

Hi see attached.

HIGH/LOW SWITCH
The HIGH/LOW switch is basically a “pad” of about -6.6dB but built in an unusual
way hence we do not simply call it a pad. The switch determines only the internal
gain of the preamp; it has no other effect on the sound.​

The attachment was the manual, which provides no information on the preamp's boost range in decibels. He ignored the question, which makes me all the more curious why fundamental information about his preamp is secret.

 

[DoubleMIDI]

So here is my email posing the question:

I have an EAP pickup for my double bass. I was wondering about the Ehrlund Preamp for this pickup. What is the preamp's range of signal boost provided in dBs? I didn't find this information on your website. Thank you.​

And here is the response from Lars:

Hi see attached.

HIGH/LOW SWITCH
The HIGH/LOW switch is basically a “pad” of about -6.6dB but built in an unusual
way hence we do not simply call it a pad. The switch determines only the internal
gain of the preamp; it has no other effect on the sound.​

The attachment was the manual, which provides no information on the preamp's boost range in decibels. He ignored the question, which makes me all the more curious why fundamental information about his preamp is secret.

I think he misunderstood the question. Ask again for the amplification of the incoming signal to the outgoing signal (switch in high position) in dB.

 

[N. Kentucky Bass]

I think he misunderstood the question. Ask again for the amplification of the incoming signal to the outgoing signal (switch in high position) in dB.

You could be right. I restated the question in these terms and have crossed my fingers for a clear response.

 

[flatback]

Just a short note that I tried the EAP onthe round back of my bass and it is the MOST acoustic mic like sound I have ever had. I think (and it sure sounds this way) that the with a round back bass the back fully vibrates unobstructed and that tone transfers to the EAP as a woody open tone. I imagine the front of a flatback would be where to put it but a round back has only one point of contact (the sound post but no bass bar and no bridge to hinder vibrations)
On my little Contrabassetto the tone is old school woody with a big sound field and vibration. It might be too much vibration with big dark basses but on mine it is excellent.
Thanks to whoever posted this tip.

 

[LaFaro01]

Just a short note that I tried the EAP onthe round back of my bass and it is the MOST acoustic mic like sound I have ever had. I think (and it sure sounds this way) that the with a round back bass the back fully vibrates unobstructed and that tone transfers to the EAP as a woody open tone. I imagine the front of a flatback would be where to put it but a round back has only one point of contact (the sound post but no bass bar and no bridge to hinder vibrations)
On my little Contrabassetto the tone is old school woody with a big sound field and vibration. It might be too much vibration with big dark basses but on mine it is excellent.
Thanks to whoever posted this tip.

As mentioned before "sometimes"...this advice I've got from Gerold Genssler purchasing the EAP from him some years ago... and it works indeed very well... if found the sweet spot(s)...

 

[Francois Blais]

I imagine the front of a flatback would be where to put it but a round back has only one point of contact (the sound post but no bass bar and no bridge to hinder vibrations)

I'm not sure I understand your comment.
Are you saying on a roundback the sole contact point is over the soundpost?
And what about the beginning of the sentence "I imagine the front of a flatback would be where to put it".
I'm confused sorry! (english is not my first language)

Thanks!

 

[flatback]

Im just saying that on the front of an instrument you have contact points (with the top) at the bass bar the sound post and the bridge. On the back (of a round back) you have only the sound post (this is not necessarily where you put the EAP...mine is much lower. On a flatback there is a lot of bracing on the back so that free vibrating plate is not so free and vibrating as it is on a carved round back.

 

[N. Kentucky Bass]

Im just saying that on the front of an instrument you have contact points (with the top) at the bass bar the sound post and the bridge. On the back (of a round back) you have only the sound post (this is not necessarily where you put the EAP...mine is much lower. On a flatback there is a lot of bracing on the back so that free vibrating plate is not so free and vibrating as it is on a carved round back.

Assuming the player is not seated with leg rested against back of bass?

 

[Francois Blais]

Im just saying that on the front of an instrument you have contact points (with the top) at the bass bar the sound post and the bridge. On the back (of a round back) you have only the sound post (this is not necessarily where you put the EAP...mine is much lower. On a flatback there is a lot of bracing on the back so that free vibrating plate is not so free and vibrating as it is on a carved round back.

Understood, thanks!
Can you show us where you put yours on the back please?
Thanks!

 

[flatback]

yeah I lean the bass on its edge against my body in order not to mute it.
I am still fine tuning the spot but about an inch from the center seam...I cut the cord so my spots are limitedif I want to keep the jack mounted on the front.

 

[N. Kentucky Bass]

yI cut the cord so my spots are limitedif I want to keep the jack mounted on the front.

Seems like physically supporting the jack interface (and preamp if you're using one to terminate the EAP) are the gating issues here. I hang my quarter inch jack on the afterlengths so not a big deal. There's no where to hang anything on the back so that would be a very long loose cable flapping around!

 

[flatback]

Well I have wads of Ischell putty that I use along the wire to keep it away from but fixed to the bass. I have my jack way down between the legs of my raised saddle, so I just wrapped the wire under the bass...seems pretty ok.

 

[Ric Vice]

I’ve found that Ehrlund EAP’s work where they work. On most basses, it’s best top mounted near the Bass bar and Soundpost. I do know of more than one instance where the bassist mounted the EAP on the back. On my Mirecourt flat back, the bracing would interfere with the sound transmission through the back which is a laminated. FRAP’s (Flat Response Audio Pickups) could be placed anywhere on the instrument. So there’s really nothing new under the sun.

 

[N. Kentucky Bass]

Has anyone tried the Fire-Eye Dee-Eye preamp with the EAP? Better, worse, same as Ehrlund's preamp? I like the Dee-Eye form factor better for a peddle board but wondering if its 1 Mohm will work compared to Ehrlund's 4.9? No idea what the dB boost is for the Dee-Eye.

https://www.fire-eye.com/dee-eye-1

 

[Ric Vice]

Haven’t tried the DeeEye. Durb (no longer on TalkBass) measured the input impedance of the Ehrlund Preamp. As I recall it was 2 Meg Ohms. I’ve run the EAP pickup, at 5 Meg Ohms and 6.8 Meg Ohms with The Headway EDB-2 and EDB-2 H.E. I’ve also run it into the Grace Felix at 1 Meg Ohm, so based on what I know it will work. Keep in mind though, that the Ehrlund Preamp, EDB-2 H.E. (0 to +32 DB) and the Grace Felix (21-62db) all boost the signal significantly. Just my take however.

 

[Bruce Calin]

I have used the Ehrlund for several years as my main pickup. I have tried others but always go back to it eventually. I have also tried several different preamps with and without the Ehrlund pre and the setup that has worked best in most playing situations is the pickup about four inches below the e-sting foot right on the bass bar directly into an original(!) Fishman bass pro platinum (without the Ehrlund pre). I'm currently using a TC electronics BQ500 and Upshot for most situations but the pickup-preamp combo has worked well with others. Responses from bandmates and listeners as well as my own impressions have been positive. I'm no gearhead and don't want anything in my setup that I don't absolutely need so it's possible that I'm settling for a lot less than MBOL or whatever but I really don't think so or care. I wouldn't bring a mic on a live-music gig on a bet. I want simple,light, and dependable and this setup has worked for me for a long time. My bass amplifies and records well so I'm fortunate there. I like seeing how people have used this pickup and am occasionally tempted to try something different but so far I haven't gone for it.