Broke Down and bought a DI

[Joe Louvar]

And why play a nice bass? I should just save a pile of money, get rid of my Roscoe, my Radial JDI, my Genz Benz amp, and get a Squier, IMP, and whatever amp.

I mean, I get the argument. I have it with myself all the time. But at some point you've serve something nice, right?

Ha, well I'm just telling it like it is...however with that said, I've also spent the extra bucks too.

 

[agedhorse]

Finishing up dinner with another touring engineer and shared this thread and I think we discovered why some experiences are so different. It has less to do with the transformer and more to do with the application of the transformer. Can't go into detail tonight but I will lay it out tomorrow when I get time, because it's a good learning experience in identifying WHU there might be a difference and why at some levels we don't see the difference.

 

[TonyP-]

In practice though, from what I see, there's not nearly as much fussing in the touring world about what DI is used as there is here on TB... imagine that

Thats because 'usually' there is already 'decent' gear out there from backline so its a non-issue.

Your right its only on TB were some makes a reference more the quality of bathroom tissue make more of a difference then the DI (paraphrasing but you get the idea).

Thats still shocks me coming from You.

 

[SteveC]

But if we didn't "discuss" these little things, what would we talk about?

(For some reason my emoticons don't work non my iphone.)

 

[TonyP-]

But if we didn't "discuss" these little things, what would we talk about?

(For some reason my emoticons don't work non my iphone.)

Good Point SteveC

 

[LiquidMidnight]

These discussions and similar debate often come up on TB. My philosophy has always been that, while yes, the audience doesn't really care at the end of the day if I have some NOS Telefunken in V1 of my amp or I decided to change the strings on my bass the night before because the top end was going on my old set or that I wired my pedal board with George Ls, it's not an excuse to take the half-assed approach to things. Doing things that are just "good enough" has been a source of contention with me and other musicians in the past, who believe that just because there are gigs on the book, it means that there's no need to improve on anything, whether that's gear, song execution, stage show, marketing, etc. I played with a band leader who would often choose not to set up a couple of LED cans because "they weren't paying him enough to set up lights," despite the fact that he was still making decent coin at the end of the show. Screw that noise. I've set up trees with dimmer packs - a lot more work than a few LED cans - to make $75, because I care about the product I'm putting out.

Granted, I concede that there has to be some reasonableness with this. I'm not saying you need to drop $10,000 on a bass rig and lug $40,000 worth of FOH and intelligent lighting to play the local watering hall or that you need an Avalon to play direct at some acoustic shows. Live sound is often a series of compromises; I get that. What I'm saying is that this good enough mentality as an excuse not to improve is not something I get down with.

 

[B-string]

I guess my question is when do you pay more attention to personal technique and your audience instead of a little "tweak" from "better" gear?

 

[Humbled]

I could understand the "good enough" argument if we were discussing whether anyone could tell the difference between a Countryman 85 and a Stewart ADB1 through a bar PA. I get that.

My problem with the IMP2 is that it imposes an impedance onto many passive single coil pickups that actually creates an eq curve at it's output that makes the signal that it sends to the board sound like some nasally junk. Given that probably half the basses being carried to bar gigs have passive single coil pickups, an IMP2 may not be an ideal choice for a main kit staple or even backup kit "all-purpose spare", because while it may do some things "well enough", it does some other things very poorly.

 

[TonyP-]

I guess my question is when do you pay more attention to personal technique and your audience instead of a little "tweak" from "better" gear?

Doesn't that go without saying as part of the course to your craft?
The thread is about DI specifically.

 

[BurningSkies]

I guess my question is when do you pay more attention to personal technique and your audience instead of a little "tweak" from "better" gear?

I have nice stuff so that when I play I can focus on the audience and the playing. Once we're playing, I'm ignoring the 'boxes on stage' and facing the crowd. Seldom do I turn my back to the audience. Also, this is false logic. Paying attention to gear doesn't mean you can't pay attention to practice, playing, technique, etc.

Doesn't that go without saying as part of the course to your craft?
The thread is about DI specifically.

Yep. Exactly. Also, having a quality DI as part of your standard setup allows you to know that you're providing good sound to FOH should it be needed. Is it overkill in some situations? Yes, but it's not like I'm going to carry a crappy DI, suss out the venue and provide a 'lesser signal' if they don't meet some arbitrary standard. Last night I chose to provide FOH through my amp rather than DI to the the 15's and subs out front. Sometimes that's the best way in a given situation too. I like having options in my toolbox, which makes for a better 'show' for a bunch of different gigging situations.

At the same time, I play with a guy (hand percussion) who's got this ridiculous setup. He's a great guy but he's got way more mics and lines and stuff than he needs...and then he submixes to the small 18 channel board we use for bar gigs. He doesn't have a handle on HOW his gear works or the ins and outs of how it needs to be most effectively run. He further complicates things by having a really really 'entry level' 8 channel mixer, not setting levels well and then using mics that are really inappropriate for the setting using $1000 sensitive studio condensers on a loud stage rather than just a handful of standard 57's or Audix stuff only makes a mess of things. He wonders why he's never loud enough in the mix, but his own gear is the reason. Just HAVING good stuff isn't enough. Also, if he had solid physical technique he would need way fewer mics. *he also doesn't realize what we're doing with the FOH sound, that he wants to send 'bass' mics (under his drums) to "fill out the low end", which is not what the mix needs nor will it ever be heard even if I wasn't high passing his signal to make those mics inaudible anyway.

 

[beans-on-toast]

It's always better to break down and buy a DI than it is to up and buy a DI.

I have a Boss DI-1 that I bought many years ago and still use on occasion. At the time it was the most affordable option. It isn't transformer based, they use op-amps for isolation and driving the line.

Despite how nice they are, not everyone needs, or can afford, a higher end model. It's all about priorities.

 

[Joe Louvar]

Finishing up dinner with another touring engineer and shared this thread and I think we discovered why some experiences are so different. It has less to do with the transformer and more to do with the application of the transformer. Can't go into detail tonight but I will lay it out tomorrow when I get time, because it's a good learning experience in identifying WHU there might be a difference and why at some levels we don't see the difference.

Where we really hear the difference is in the studio.

 

[LiquidMidnight]

I guess my question is when do you pay more attention to personal technique and your audience instead of a little "tweak" from "better" gear?

I think it's a false dichotomy (or trichotomy?). All of those things are important.

 

[agedhorse]

Ok, here's where I think the (gross) misunderstanding is coming from.

The OP has all active basses, and my responses were in the context of the OP's situation and specifically the OP's choice of DI's.

An active bass typically has an output impedance of between 100 and 5k ohms. Passives typically have an output impedance of between 10k and 150k.

With an active pickup, the response is quite load insensitive. This means that a typical (as in run of the mill) DI transformer that might have an input impedance of say 50k ohms, and while it's not just a single number, any variation is an tiny factor in the transformation where the ratio of the source impedance to the load impedance is so large. 100:50k is what makes a typical DI transformer work so well in this application.

With a passive pickup, the response becomes more load sensitive because the ratio is no longer as steep. A passive pickup with an output impedance of say 10k would have a 10k:50k impedance transform and the response would vary much more greatly than with the 100:50k impedance transform. Take this farther to a 50k output impednance pickup and you have a 50k:50k (or 1:1) transform which would be much more sensitive to the effects lo loading. NOW, if you take an active DI with an imput impedance if 1M, and with a source impedance of 50k, you have a 50k:1M transform which is back to a ratio where the effects of loading are mitigated by the more favorable ratio.

These effects, because the source AND load impedances are reactive and not just resistive, interact to magnify or skew loading effects and are what is primarily responsible for the negative impression of passive DI's when used with passive pickups, but this seems to have carried over to ALL pickups which in my fairly extensive testing, is not an accurate global statement.

So, IN THE CONTEXT OF THE OP's basses, the situation he described, and his choice of DI, I think it's an adequate choice.

Perhaps I incorrectly assumed that folks would understand the choice of tools to accomplish the task were already understood. In the pro audio world, amongst pros anyway, this concept of impedance ratios is pretty elementary. It's not because we are arbitrarily pulling the "DI of the day" out of our workbox, some thought goes into choosing the tools of the trade. Sometimes, in very high RF enfironments, I will choose a DI that maybe doesn't have the highest possible audio quality, but has another quality that is MORE important for that particular situation. With a high RF envoronment, I carry some custom DI's that include additional Faraday shields between the primary and secondary so that I can achieve even greater ground isolation while limiting capacitive coupling internally from primary to secondary, preventing (or reducing) RF (radio, hash, high level carrier induced distortions) from degrading the signal. These transformers don't sound quite as nice as the ones without the shields but they sound a hell of a lot better than the RF artifacts. Even where it's a passive pickup and the active DI has challenges (and the challenges may be present in the amp as well, so micing just carries the noises forward), these passive DI's might just be the best alternative available FOR THE SITUATION AT HAND.

Tony, if what I said previously shocked you, perhaps you misunderstood the context that is was presented in.

 

[Humbled]

So why does the same passive bass that sounds awful with a passive IMP sound great with a passive JDI?

 

[SteveC]

Because JDI's are awesome! My passive Geddy Lee jazz sounded great through my JDI.

 

[Humbled]

I was hoping to get an electronic explanation from a professional.

 

[SteveC]

My "awesome" explanation isn't enough? ;-)

 

[agedhorse]

I received a PM from a forum member that wished to remain unidentified that asked some good questions that I think are best answered here because they go directly to my comments about focusing on what's important, or what's likely to make a practical, real world difference, rather than on what's sexy.

Question 1: I am having trouble in some rooms getting the bass to have a round response down low. In some ranges it almost goes away but in others it's a little too loud. Could this be my DI?

Answer 1: Well the first thing to determine is what the cause of the level changes are from. This may give a clue as to what might be responsible. What happens if you just play the bass with the amp on stage, no PA? Do the level changes go away? Do they get better? Now play the bass through the PA only. Do the level differences remain? The MOST LIKELY cause(s) are due to the acoustic properties of the room/stage interaction along with the bass amp. Wherever you have long waves and large room dimensions, the resulting acosutic energy will represent a diffraction pattern where there will be sum and difference responses (peaks and dips) depending on the levels of both sources, the positions of both sources and the dimensions of the room. Every surface represents a reflective boundery. To use the water in the tub analogy, drop one pebble in the water and you get a (planer) spherical wave pattern. Drop 2 pebbles and you will get 2 spherical wave patterns. Where they intersect you will get peaks and valleys. now looking at the reflections from the walls of the tub, there will be reflections that will create additional peaks and valleys. Where the distances are multuples of the fundamental (and in the case of bass guitar, the dominant harmonics), these sums and differences will multiply at selected points in the "tub". These waves change with frequency (note) so there is a series of these patterns as a result. Where the player is standing may be be in a peak for some notes but transition into a valley for others. Short of changeing the room's boundery acoustics (done in some performing arts halls with variable acoustics systems), a better COMPROMISE (to clarify that it's not an absolute fix) might be to change the level or position of the bass amp, the player, or even the relative positions of the two sound sources (PA and bass amp). One way that this can be done (may not be obvious) is to delay the subs back a few feet electronically to see if the diffraction pattern can be modified so that it's not as intrusive to the player, though it's best for the FOH guy to walk the room to insure that he didn't "fix" one problem by creating another. This is a case of where I wouldn't automatically blame the DI, because the symptoms indicate other much more likely causes.

Question 2: How do bass players hear themelves on larger PA's where there are a lot of subs?

Answer 2: Well, one way is to block out as much ambient noise as possible with in-ears, but for bass players that might not be as effective because the STC (sound transmission coefficient) of in-ears is not generally as good at the lower frequencies. Often, what might be a better choice, is to reduce the bass amp's (or monitor system) low end and concentrate on 100Hz on up since mucg of the sub 100Hz information is being wrapped around the subs onto the stage causing what you are hearing. Now your rig provides 100Hz+ and the PA subs provides the 100Hz-. Yeah, I know this goes against having "YOUR" perfect sound on stage, but that's already been compromised by the PA and the room. If you are going to play on big, loud stages with big PA, you prpbably need to get over having "perfect stage sound". Another way that's been experimented with for the past few years is directional subs. This involves intentionally altering the response pattern (remember that sub frequency wave pattern is spherical) by adding an out of phase or phase shifted signal to null or subtract from the signal going backwards. If you have enough PA (this can take as much as 50% more subs) the results can be "meh" to quite reasonable. I have seen both outcomes.

Question 3: How do I determine what kind of DI is "right" for my bass?

Answer 3: The general rule of thumb is that for a passive bass you will probably get better results with an active pickup because the input impedance of the DI better interfaces with the higher impedance of the bass pickups. With an active bass, I generally prefer passive DI's because of the additional isolation that can be achieved from a typical active DI. (there are exceptions, but this is a good generality). I also tend to stay away from active DI's because of added noise (sometimes inaudible but sometimes quite significant), and the fact that active DI's tenc to be less reliable, and with phantom power, tend to pop and crackle if there are any intermittent connections/contacts.

Question 4: How would I pick one DI over another?

Answer 4: I generally suggest trying several out and if, over the PA systems that you will be using it with (or recording systems that you will be using), choose the one that has the best sound for the amount of money that you are willing to spend. Reliability has to be considered also, of course. If you can't hear the difference, then believe your ears and there may not be a difference regardless of what the marketing and the salesman might otherwise suggest.

Question 5: What's the best toilet paper?

Answer 5: The one that doesn't have an empty roll.

 

[Humbled]

My "awesome" explanation isn't enough? ;-)

You do score points for succinctness and accuracy.