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Double Bass NEW Euphonic Audio iAMP Doubler
- Thread starter peterpalmieri
- Start date
50 hz is WAY too high. A hpf for bass needs to attenuate the subsonic garbage amplified by piezos. 28 hz is probably good. Certainly no higher than 35 hz. The bass will sound like a Twinkie with a 50 hz high pass. Mike---do you know the slope of the high pass? 24 db per octave?
Mike,
That's interesting since FDeck's HPF/Preamp sets it's floor at 35 hz. I can certainly tell the difference when you raise the settings, but therer are a couple of halls I play in that force me to set the HPF a little above 50. It's not ideal mind you, but occasionally I have to use it. Perhaps, that's why the notch filter is a better solution.
Ric
I am just a part-time pro as outlined in my profile. And with all due respect to Mike A. ...
I use a HPF routinely set as high as 70 Hz, and I've never been accused of sounding like a Twinkie.
I think it may depend on the slope, the type of piezo, and how that piezo performs on a given bass. Not to mention the ability to tune it to the room or hall. The HP I use most often has a 12 dB per octave rolloff.
I own an EA combo amp, and one of their M-line cabs. And I blend a pickup and a mic on almost every gig. So I guess I am part of the target audience for the Doubler unit. Of course maybe I'm an idiot ... but
An adjustable HPF would be cool. That's all.
Twinkie. Funny.
At EA we try to be VERY responsive to the desires and needs of each player, whether a pro or hobbyist. This is evident in the amount of input that Bob G, Mike A and others such as Mark Calson from the Setup Shop have had in the design and implementation of the Doubler. As we are still in the prototype stage, things can still change and be adjusted. Perhaps I did not clearly state that. Since Mike A. is the "daddy" of the doubler we will be sending him one of the prototypes for evaluation within the next ten days or so.
I would sincerely ask that each of you realize that we are building this amp for you and post here to get your input and answer your questions. We, obviously, cannot implement everything that everybody wants and some compromises need to be made. We hope that your responses are positive in nature and not get into arguments or hyperbole. We can evaluate all these responses, make some tests and see what sounds best, what is possible to implement and what is not. It is your thoughtful responses that are truly helpful. This is the only way we can truly be responsive to your wants and desires for the best amp possible.
That being said, we will look further into the hpf.
Thank you and Happy New Year
Mike Dimin
EA Amps
I would sincerely ask that each of you realize that we are building this amp for you and post here to get your input and answer your questions. We, obviously, cannot implement everything that everybody wants and some compromises need to be made. We hope that your responses are positive in nature and not get into arguments or hyperbole. We can evaluate all these responses, make some tests and see what sounds best, what is possible to implement and what is not. It is your thoughtful responses that are truly helpful. This is the only way we can truly be responsive to your wants and desires for the best amp possible.
That being said, we will look further into the hpf.
Thank you and Happy New Year
Mike Dimin
EA Amps
When I first saw that the HPF had a fixed corner of 50 Hz, I thought, "Whoa, too high" but I didn't want to start in.
Well, you all started in for me so here goes.
The fundamental of the E is around 42 Hz or so. Some of us, myself included, use a HPF mainly for attenuating infrasonics (not "subsonics") that can rob the amplifier of power and drive speaker cones crazy. The HPF can also be used to tame troublesome rooms so having the option of raising the corner frequency is a nice one. That's what you get with fdeck's little gem.
If the corner frequency is to be fixed, then in my opinion, it is best to fix it at a point where it will act to tame infrasonics and will not attenuate any potentially desirable part of the response. That's why 50 Hz is too high. In fact, that would keep me from ever buying the product.
It is true that some sources such as vinyl, FM stations, reproduction chains, etc. often involve attenuation of frequencies below 50 Hz or, perhaps, even 100 Hz. Keep in mind though, that we are not discussing musical reproduction but, rather musical reinforcement. The practicalities of reproduction often involve compromises, (e.g., compression, band-limiting, gain-riding, etc.) that can often and should often be avoided in live performances. This is one of the reasons that live performances can (but, sadly, often do not) have more impact than recorded ones.
Returning to the HPF itself, no, notch filters are not more desirable, unless we are discussing control of feedback or the taming of a particularly nasty resonance. Even in such cases, a good HPF is invaluable to get rid of potential infrasonics.
In short, if a fixed HPF is provided, its corner frequency should be placed well away from any of the frequencies that may be desirable to reinforce. When it is desirable to have them, the player should have the option of having them there.
The choice of the lowest corner of 35 Hz on fdeck's HPF was made with good, sound (pun intended) reasoning. Not only is it below the fundamental of the E (sorry, low-B players) but it is also right in the region where many ported cabinets have their resonance. EA would be wise to set theirs lower than 50 Hz.
Now a bit about slope. If the slope (rate of attenuation) of the EA filter is using is, say, -6 dB/oct, then the frequencies just below 50 Hz will not be attenuated by much so those often-desirable very low frequencies would not be too much affected. The flip side of that coin is that the infrasonics will also not receive the desired amount of attenuation. The HPF in fdeck's device has a slope of -12 dB/oct with the lowest corner (as noted above) placed at about 35 Hz. The result is that the desired low frequencies are retained and the infrasonics are effectively vanquished. These choices were not made by accident!
Well, you all started in for me so here goes.
The fundamental of the E is around 42 Hz or so. Some of us, myself included, use a HPF mainly for attenuating infrasonics (not "subsonics") that can rob the amplifier of power and drive speaker cones crazy. The HPF can also be used to tame troublesome rooms so having the option of raising the corner frequency is a nice one. That's what you get with fdeck's little gem.
If the corner frequency is to be fixed, then in my opinion, it is best to fix it at a point where it will act to tame infrasonics and will not attenuate any potentially desirable part of the response. That's why 50 Hz is too high. In fact, that would keep me from ever buying the product.
It is true that some sources such as vinyl, FM stations, reproduction chains, etc. often involve attenuation of frequencies below 50 Hz or, perhaps, even 100 Hz. Keep in mind though, that we are not discussing musical reproduction but, rather musical reinforcement. The practicalities of reproduction often involve compromises, (e.g., compression, band-limiting, gain-riding, etc.) that can often and should often be avoided in live performances. This is one of the reasons that live performances can (but, sadly, often do not) have more impact than recorded ones.
Returning to the HPF itself, no, notch filters are not more desirable, unless we are discussing control of feedback or the taming of a particularly nasty resonance. Even in such cases, a good HPF is invaluable to get rid of potential infrasonics.
In short, if a fixed HPF is provided, its corner frequency should be placed well away from any of the frequencies that may be desirable to reinforce. When it is desirable to have them, the player should have the option of having them there.
The choice of the lowest corner of 35 Hz on fdeck's HPF was made with good, sound (pun intended) reasoning. Not only is it below the fundamental of the E (sorry, low-B players) but it is also right in the region where many ported cabinets have their resonance. EA would be wise to set theirs lower than 50 Hz.
Now a bit about slope. If the slope (rate of attenuation) of the EA filter is using is, say, -6 dB/oct, then the frequencies just below 50 Hz will not be attenuated by much so those often-desirable very low frequencies would not be too much affected. The flip side of that coin is that the infrasonics will also not receive the desired amount of attenuation. The HPF in fdeck's device has a slope of -12 dB/oct with the lowest corner (as noted above) placed at about 35 Hz. The result is that the desired low frequencies are retained and the infrasonics are effectively vanquished. These choices were not made by accident!
Hey Rob
I've always thought the same as you until I got an EQ with a variable 24db per octave HPF. Now, the speakers we use really give us little information under say, 60hz. The lowest note on a (regular) bass is 42 hz. So, if I set the knee on a 24db per octave HPF at 42 hz there is no way I should be able to tell the difference, right? The bass sounded great, but didn't FEEL great. It felt like I was listening to a great recording, but the thump of each note was nearly gone. I also noticed that without a filter that when looking at the speaker cone it moved almost as much with the G string as the E string. This is because there is some useful information below 42 hz and some useless information. The thump of a note ( probably the single most functionally important element of our sound in jazz) is below the 42 hz range. Now since our speakers relay so little information in that area the difference should be negligeable, right?
Well for reasons I don't necessarily understand there is a difference. I've tried it many times in many situations. (and with different eq's just to make sure) The information below 30 hz is useless and drains power and dynamic range. I've told people for years that when they hear a deep, slammin upright sound that they are really hearing the first harmonic and not much fundamental. Maybe it relates to the psycoaccoustic aspect (like how you hear someone with a deep low voice on the phone ). If with the double bass the 42 hz region was measurably the same as , say the 200 hz region in terms of volume, the bass would sound ridiculous, like a reggae bass. But for some reason, if you set a HPF knee even at 42 hz, my experience is that there is a noticable loss in thump and visceral impact.
I've always thought the same as you until I got an EQ with a variable 24db per octave HPF. Now, the speakers we use really give us little information under say, 60hz. The lowest note on a (regular) bass is 42 hz. So, if I set the knee on a 24db per octave HPF at 42 hz there is no way I should be able to tell the difference, right? The bass sounded great, but didn't FEEL great. It felt like I was listening to a great recording, but the thump of each note was nearly gone. I also noticed that without a filter that when looking at the speaker cone it moved almost as much with the G string as the E string. This is because there is some useful information below 42 hz and some useless information. The thump of a note ( probably the single most functionally important element of our sound in jazz) is below the 42 hz range. Now since our speakers relay so little information in that area the difference should be negligeable, right?
Well for reasons I don't necessarily understand there is a difference. I've tried it many times in many situations. (and with different eq's just to make sure) The information below 30 hz is useless and drains power and dynamic range. I've told people for years that when they hear a deep, slammin upright sound that they are really hearing the first harmonic and not much fundamental. Maybe it relates to the psycoaccoustic aspect (like how you hear someone with a deep low voice on the phone ). If with the double bass the 42 hz region was measurably the same as , say the 200 hz region in terms of volume, the bass would sound ridiculous, like a reggae bass. But for some reason, if you set a HPF knee even at 42 hz, my experience is that there is a noticable loss in thump and visceral impact.
By the way, hi Mike and congrats to you and your wife. And for everyone else out there, I can't say enough good things about Mike and the other people at EA. They are consistantly a joy to work with. When I was choosing amps and speakers I went with EA because I thought that they had the best gear. It has been an unexpected benefit that they also are some of the nicest and most responsive guys to deal with.
One of the really great things about getting to work with Mike A. is that he really has great ears, knows what he wants and can effectively communicate it. If you need proof just listen to the tone that he gets. It is one of the best upright tones that I've heard.
Mike
The speaker who uses? There is actually plenty of useful sound pressure below 60 Hz from many of the cabs we all discuss here. As for hi-fi speakers, the ones I use have "usable" output down to 12 Hz! Yep, I do love bass. No, there are not many sources that contain information down there. Still, if you've ever heard the pedal tone in the Saint Saens organ symphony reproduced on a good system, you will quickly understand the value of spectral content below 60 Hz!
Well, wrong for two reasons.
First, there is usable energy radiated below that frequency. Second, what no one has discussed here is the spectral content of the impulse that occurs at the onset of each note. It is rather broadband and short-lived.Actually, the phenomenon to which you are alluding is the restoration of the pitch of the missing fundamental. That's quite different.
"Volume" is a psychological term. Now, if the physical acoustical energy were the same at 42 and 200 Hz, then the loudness of the former would be much less until very high sound-pressure levels were reached.
Let's talk a bit more about the impulse and the "thump." When the DB is amplified, the pickup will usually transmit the broadband impulse that likely contains energy at very low frequencies. Add a HPF and some of that energy will be removed, resulting in less impact.... BUT-- is that energy that would normally be radiated to any substantial degree at the ears of a listener in front of a DB played solely acoustically? The answer is no. In truth then, the "thump" is largely an artifact of amplification that you and many may find pleasing and desirable. If the holy grail of DB amplification is "the acoustic sound but bigger," then you really don't want it.
Well hopefully I can take the high road and have better manners than the previous post.
We are not in the business of sound reproduction. We are in the business of sound production. I'm playing the devil's advocate to a degree, but our first priority as jazz double bassists is playing quarter notes that " drive" the band.The best models we as double bassists in jazz have in terms of sound are live concerts ( which for the past 35 years have been dominated by bad pickup sound or miked basses where the drums have been louder than the bass) or recordings. A miked bass on a recording does not sound like the bass at even a 10 foot distance. The bass is typically close miked. This has been our model of a good jazz sound. When the bass is close miked, there is a discernable "thump" as part of the sound. It is a non-pitch sound similar to a damped bass drum. It is as present on a G string as an E string.
And also, by the way, I own Innersound Eros speakers and a very high end system. Problem with high end audio is that most owners of high end systems listen to stereo systems first, music second.
We are not in the business of sound reproduction. We are in the business of sound production. I'm playing the devil's advocate to a degree, but our first priority as jazz double bassists is playing quarter notes that " drive" the band.The best models we as double bassists in jazz have in terms of sound are live concerts ( which for the past 35 years have been dominated by bad pickup sound or miked basses where the drums have been louder than the bass) or recordings. A miked bass on a recording does not sound like the bass at even a 10 foot distance. The bass is typically close miked. This has been our model of a good jazz sound. When the bass is close miked, there is a discernable "thump" as part of the sound. It is a non-pitch sound similar to a damped bass drum. It is as present on a G string as an E string.
And also, by the way, I own Innersound Eros speakers and a very high end system. Problem with high end audio is that most owners of high end systems listen to stereo systems first, music second.
Huh?
Wow, you really read that wrong! The post was straightforward and objective. Gee, even included the to make it clear that I was not being critical.Yes, indeed, that was one of my main points in post #87!
I disagree that these are our best models.
Agreed. Interestingly though, this type of "thump" that one gets from miked recordings is not likely to contain those very low frequencies that were the subject of my previous post and yours.
Agreed as well-- I know too many of those! Thankfully, I'm not one of them. Mike-- please do me a favor and re-read my post without assuming a negative or condescending tone. I was trying to explain to you and others here who are interested, just what is going on acoustically (and psychoacousticaly) under the conditions you mentioned. In your own post, you said, "Well for reasons I don't necessarily understand there is a difference." I was attempting to demystify some of your experience. That involved pointing out that some of the assumptions you made just don't square with the physical acoustics. That's not bad manners.
I use a HPF routinely set as high as 70 Hz, and I've never been accused of sounding like a Twinkie.
Me, too. And before I owned an amp with an adjustable HPF (AI Clarus), I would often just turn the bass knob down. It has nothing to do with faithfully representing the acoustic sound of the bass (how could it, with a transducer to begin with?) and everything to do with getting a usable sound in whichever room we happen to be in tonight.
And when I use a mic live, I have it so close to the table (an inch or under) that I find myself cranking the HPF to battle what I assume is the proximity effect. With the Clarus, the channel into which the Heil PR40 goes has the HPF at 10 o'clock (whatever that may be) and the bass knob down to 9 o'clock. And it sounds just right!
So, I like an adjustable HPF, and I'd love to see one on the new EA amp because the AI Clarus has never sounded as good to me as the Iamp I used to own; I keep using it, though, for the supreme functionality it offers.
Thanks Mike for the mention and I am looking forward to the New iAMP Doubler to hit the market.
I have been a Micro 300 owner for a year now and a Wizzy 10 and M-line user for a couple of years and I am so happy every time I go to the gig because it is SO EASY to get a great sound w. this gear... This new addition should be one of the great products of this new year..
Can't wait and best to you Mike and the boys at EA... Happy 2009.
+1 to all. The numbers are interesting in an abstract kind of way, but it's the sound on the bandstand that matters. In some rooms, I set the HPF on the Focus at high noon, which allows me to refrain from lowering the bass controls.
There's another piece to the puzzle which doesn't get talked about too much. When you play a low E on a double bass, how much of what you are hearing is the fundamental and how much is the second partial? What's the balance? Technically, the string length of the bass on an open string - usually from 40-42" or so - is too short to accurately produce the full effect of the fundamental anyway, isn't it? The string length on a concert grand playing that same note is much longer, and the string is noticeably thicker as well. Horns that produce that note have more tubing length than the length of an open bass string as well. I'm not sure how to quantify this, or that it matters, but I have a strong feeling that all of this stuff comes into play as well.
Hi,
I have not read all posts regarding the 50 Hz roll off, but here are my two cents:
1) The 6 db rollloff is very gradual. For a 4 string the HPF should be barely audible, for a 5 string this may be just the right thing to keep the balance (My lob B is way too loud).
2) Look at this as a system - most bass players boost bass. The 6 db HPF may be just the right filter to keep this system in balance.
3) Ampeg 8x10 rolls off at 50 Hz (12 db/octave) . I have not heard anyone say this speaker is thin sounding. EA speaks roll off lower, so between the EA Speaker and the HPF you probably still have more bass....only that EA cuts the power, Ampeg justs stops being efficient.
4) Everything is theoretical until you hear and play it. I have the iAMP800 and its great. I would not assume EA suddenly forgot how to make bass amps......
5) I am looking forward to test drive one....
Wolfram
I have not read all posts regarding the 50 Hz roll off, but here are my two cents:
1) The 6 db rollloff is very gradual. For a 4 string the HPF should be barely audible, for a 5 string this may be just the right thing to keep the balance (My lob B is way too loud).
2) Look at this as a system - most bass players boost bass. The 6 db HPF may be just the right filter to keep this system in balance.
3) Ampeg 8x10 rolls off at 50 Hz (12 db/octave) . I have not heard anyone say this speaker is thin sounding. EA speaks roll off lower, so between the EA Speaker and the HPF you probably still have more bass....only that EA cuts the power, Ampeg justs stops being efficient.
4) Everything is theoretical until you hear and play it. I have the iAMP800 and its great. I would not assume EA suddenly forgot how to make bass amps......
5) I am looking forward to test drive one....
Wolfram
We don't yet know what is the slope of the new EA HPF. As I explained earlier, -6 dB/oct would be a poor choice. That comes from theory AND practice.
It takes into account the desirability of attenuating infrasonics and the typical responses of the cabs we use.
