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Direct Out Question
- Thread starter KatKlysmik
- Start date
The dB’s don’t get routed. That symbol, dB, is short for decibel, a measure of amplitude, or volume, if you will.
This is sort of esoteric, but dBs can be used to measure all kinds of signals. For amps it’s usually voltage in the circuit (that’s what the reference dB for the DI you read is about) and sound pressure, aka acoustic sound volume. Often abbreviated SPL for “sound pressure level”.
That manual was just saying that about 6 dB of gain, perhaps on average, are added to the input signal from your bass (the electric information your bass sends down your cord to the amp == “signal”) when it sends the signal to the DI.
The signal can get split and manipulated lots of different ways in an amplifier.
The equalizer, or EQ, in your amp’s pre-amp section modifies the signal. And finally the power amp section of your amplifier adds a lot of gain, enough to drive the speaker cabinet and make loud sounds.
There are definitely other stores I've been to in the past with helpful and knowledgeable staff in other cities.
Well sort of. It depends on the voicing of your cab. For instance, Eden XST cabs have very flat frequency response across the spectrum they cover. Those type of cabs are often called "Hi-Fi" cabs. Yet the Eden XLT cabs have a low-mid hump (boost in the low-mids). That is a cab that has what's known as "baked in voicing". If the cab you were using is a Hi-Fi cab, then yes, the post EQ DI send is going to sound very similar to what is coming out of your cab. However, if you have a cab with baked in voicing, like the Eden XLT cabs, the sound will be different because the FOH will probably not be using cabs with a built-in low-mid hump. They would need to add a little boost in the low-mids to get close to the sound that the Eden XLT cabs naturally produce.
Another consideration is that the sound out front sounds different than the sound on the stage and the sound guy is adjusting your sound for what he's hearing at his sound board. That's why the sound boards are often in the middle of the venue. They usually like to have a "pre" signal sent to the board for them to sculpt as needed. I've done it both ways and one recommendation I would give you is to talk to the sound tech. I always do that. I typically do dial in some boost to about 1:30 at either 250Hz or 500Hz depending on the amp I'm using, because I am using Hi-Fi cabs by DNA, not Eden XLT cabs. So I'm sure to tell him what it is that I'm sending him and what sound I'd like to get. If he's good at it, he'll make me sound good without having to guess what settings he's actually getting.
I'm planning on getting a small portable amp and maybe a 1x15 cab that's easy to transport. Hoping that the PA would do the job of making me heard adequately. But I'll definitely take your advice and speak to the sound guy and let him know how I think I should sound. Do you think a 300W rms amp and cab will get the job done for a medium sized outdoors gig?
Just don't take it personally if he doesn't seem to be paying too much attention to you.
I'll write it down on a post it and tack that to his board!Just don't take it personally if he doesn't seem to be paying too much attention to you.
Well crap! On outdoors venues, all bets are off on how many watts you need. That's because you may just be playing in wide open spaces with nothing to reflect your sound. So the outdoors just sucks up your sound. Indoors your sound is reflected off all the walls as well as the ceiling and floor. When there are no walls, ceiling, or reflective surfaces, it takes a lot louder amp and cab to fill in the space.
Unless you are playing large outdoor events, I wouldn't count on the venue having an FOH system that you could plug into. If they do have it, great! Then your 115 will probably be OK for stage volume. In my experience, medium-sized outdoor venues rarely have an FOH system where you can plug in or mic all the amps. You're lucky if they have a PA that you can use for the vocals.
How loud you are also depends on how sensitive your cabs are. Sound Pressure Level (SPL) rating is basically a measurement of how many db the cab will produce with 1-watt of power at 1-meter (2.83v into 8Ω). From that point, it takes double the power used for each additional 3db in Sound Pressure Level (SPL) at 1-meter. And to confuse things more, the SPL from most manufacturers is measured with a 1KHz test tone. And of course we play a lot more frequencies than 1KHz.
To my knowledge Mesa is about the only one who measures the SPL at multiple frequencies, posts the results, and then posts an average. That's all thanks to @agedhorse who designs them. Because of those tests at multiple frequencies, the Mesa SPL average may be lower than other competitors SPL ratings while his cabs are actually louder in real world conditions. If the cab maker lists a Max SPL, be sure to check that out in conjunction with their SPL rating.
My DNS cabs by DNA are very efficient and extremely loud cabs. 400-watts is usually enough for outdoors, which is what my DNA-800 (class D 800-watt amp) will deliver to my 8Ω, DNS-410 cab. However, if I need more than that, I run my class A/B, Eden WT500/800 amp, bridged at 800-watts into that same cab. But I always use my 410 when playing outdoors. It just pushes more air which fills the open spaces better.
So my opinion would be to get at least a 400 or 500-watt rms amp and run it into two 210 cabs for outdoors. If you decide to go with a 115 cab instead of a 210...get two 115 cabs because you'll need them. There are very few things worse for a bass player than not having enough rig for the gig. Been there, done that, hated it! Swore it would never happen again! Believe me when I say, "you don't want to be that guy."
You mean I wont be heard going into a portable 2 speaker outdoors PA? Theres gotta be a PA right? If ours isnt the only band that day.
And why 2 15 inch cabs? Do I stack them up? Or have one facing the front and another pointing at me?
Based on what you're telling me, the only gear I can find with my limited resources is probably a used SVT7 head (the newer solid state kind). And maybe wing it with a diy 410 plywood cab. That way I just turn up the volume if theres no di out.
If it's one of those Phonic / karaoke type PAs, nope. You're pretty much on your own. What exactly is "limited resources"? As mentioned, the DI is the least of your concerns and can be added at a later time. On the plus side, we can easily cobble-together some perfectly serviceable rigs with used / old tech / obsolete yet functional components.
Riis
No, that kind of PA is limited in how much bass support it can provide.
Sorry I meant I dont have much to spend on gear. And there isnt much available used around here. Unless I go for stuff that's 20+ years old and beyond. Maybe broken amp heads. Then the options open up. I can replace a cap or 2 if they're obviously bulging, I know how to solder. It might take more time for me to learn how to troubleshoot the circuitry since I know next to nothing about amps. Amp techs may cost more than the gear. So if I go down that path I'll have to pick up some amp repair skills. Which I'm prepared to do if necessary. Ask not what your bass can do for you, but what you will do for your bass!
- Feb 12, 2006
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- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
I think you will discover that learning the skills necessary to repair amps properly is a lot harder and more time consuming than you imagine.
DI out is actually mic level, not line level. The idea is to get a mic level signal so it could be plugged into a mixer. Some active DI boxes let you choose line level, but passive DI output is mic level.
Sorry I meant I dont have much to spend on gear. And there isnt much available used around here. Unless I go for stuff that's 20+ years old and beyond. Maybe broken amp heads. Then the options open up. I can replace a cap or 2 if they're obviously bulging, I know how to solder. It might take more time for me to learn how to troubleshoot the circuitry since I know next to nothing about amps. Amp techs may cost more than the gear. So if I go down that path I'll have to pick up some amp repair skills. Which I'm prepared to do if necessary. Ask not what your bass can do for you, but what you will do for your bass!
Heck, nothing wrong with 20 yr old Bass amps (in a lot of cases).
Maybe look for an older Peavey Bass Head. I picked one up for my practice space (so's not to lug gear back n forth) for the low low price of $99. YES 99 US dollars. (Peavey MK IV xp, I think?.) It was in decent shape, but had an Italian flag (poorly) painted on the top. Those 'ole Peavey usually last forever, sound decent (loud) enough. Then spend the "good money" on a decent Speaker cabinet.
Don't listen to the naysayers that say peaveys suck. Dependable, solid (usually heavy
old workhorses and Made in the USA- if thats your thing. (not sure where you from, actually).YMMV
Good Luck
T$
I recommended 2x115 cabs if you want to run 15's outdoors because I toured for 3-years playing through a 215 rig back in the 70's. It was a Standel piggy-back amp (MCIIb/SAM30b) and it was as loud as the acoustic 360 and a bit louder than the SVT at the time. I've also gigged with a Yamaha 115 combo back in 1997 and it was barely enough for a small outdoors venue. Be aware that typically the 115's will not be as snappy or as crisp as a 210 cab because 10's typically have faster transients. It just generally takes longer for a 15" speaker to move than it does for a 10" speaker.
Also, in many brands, the 210 cab can generate lower frequencies better than a 115 can. It used to be that if you wanted full lows, you went to 15" speakers and if you wanted punch you went to 10" speakers. Lines have become badly blurred over the last decade or so with 210's often producing the best punch (snappy and crisp) as well as the lowest and most well defined lows.
If the venue is running multiple bands on the same day, then yes, I would expect them to have a PA set up for the vocals. It may or may not be set up for you to just plug into. I would be amazed if your group let you put your bass through a 2-speaker, tripod PA or if the venue would let you run your bass through to their 2-speaker PA on a stick system either, if that's what they have. Bass is really hard on speakers unless they are made specifically to accommodate them. Check with your venue ahead of time to find out what they have and how you can use it.
And Yes, you would want to stack the 115's one on top of the other. Besides getting an extra 3db for running twice as many speakers, you also get an extra 3db for stacking them because of the sonic coupling. Plus having it closer to your ear makes it easier for you to hear what you're playing. 115's tend to shoot all their sound out towards your knees.
One of the groups I play with has their own 15", 12", and 10" PA systems plus 12" and 15" monitors. There's no problem running through these JBL and Mackie systems, but outdoors they usually ask me to run through my amp because it's easier on their speakers. If they do run me through the board, they'll have me go through one of the channels on the sound board that has compression available on it to protect their speakers.
• For small venues we'll use our 10" PA speakers (JBL) for the vocals and sometimes run the guitars through them. I usually bring my small venue rig, which is an Eden TN226 class D amp (4.7-lbs) and an Eden EX-112 cab - all fits nicely on a chair and is easy to carry in and out.
• For medium venues we will usually run the JBL 12's on tripods for the vocals and everyone will use their own amps. I'll use my DNS-210 here.
• For Large indoor venues we will use the 15's on the tripods and use the 12's for monitors at our feet. I still just use my DNS-210 because it can handle 700-watts rms and is very LOUD!
• For outdoors we usually will put the Mackie 15's on the stage floor with the 12's on tripods or stacked on top of the 15's. And of course we have monitors on the stage for us. We still typically use the PA only for vocals although sometimes the guitars will run through them. Outdoors I use my DNS-410 cab.
Having said that, there were a couple of places that were specifically set up for the groups to run through the board entirely and they both had very competent sound techs that ran sound all night for us. In that case I ran through my WTDI, which is a DI stompbox with a built-in Eden WT preamp. It only weighs about a pound and I can make anything sound like one of my Eden or DNA amps with it.
I just plug a balanced line from my WTDI into the soundboard's snake, let the tech know I added a slight boost to the low mids at 500Hz, and away we go. They both had a dedicated sub-bass cab to handle the very low frequencies (down to 20Hz). Most places don't provide such great equipment with a skilled person to run it. So find out what your venue is going to supply before you go there so you don't get jammed up with not enough rig for the gig.
I really would recommend that you don't try to build a DIY 410 cab unless you understand the Thiele-Small parameters for bass cab construction and use them to determine which speakers should go in the cab as well as what ports to use (round, flared, or shelf), how deep they need to be to tune them to the interior dimensions of the cab, and where to place the ports. Slapping four 10's in a DIY box for guitar is not so difficult, but for a bass cabinet it's critical to match the speakers to the cab to get decent sound and anywhere near the power handling that they speakers say they have. It can be done but you really need to know what you're doing. It's real easy to buy the best components and end up with
for a bass cab.Regarding your thought to use an Ampeg SVT-7PRO, that should work fine. At 15½-lbs, it's heavy for a class D amp, but still lighter than the old class A/B solid-state amps. Be aware that it will put out 600-watts into 8Ω and has a minimum ohms load rating of 4Ω. That means you can plug two 8Ω cabs into it, but you can't plug two 4Ω cabs into it without damaging and possibly ruining the amp.
With one cab at 8Ω it will put out 600-watts. So be sure the speaker cab you are looking at will handle that much power or at least close to it. When you add the second 8Ω cab, that will drop the ohms load down to 4Ω and that amp will be able to deliver all 1000-watts. It will split them equally between both cabs, so each cab will get a max of 500-watts. Do not try to use cabs with only 300-watts handling power with it though. If you crank it up, you will blow the speakers right out of cabs rated to handle 300-watts.
Thank you so much Rip. I shall take your advice and buy a cab with the correct rms/ impedance numbers. Those were some great tips you shared.
