between the pre and the amp
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Bob I'm getting a bad vibe from you question. Are you planning on using an equalizer or are you already set up with one in a way that is different from what was suggested by Jaybo and myself? Are you an engineer? I can't figure why you are calling a preamp an attenuator? It's a preamp!!!! I don't think Joey asked any questions about an attenuator. See I don't like calling speakers transducers either. Keep in mind, we are trying to assist Joey and in my experience preamp receives signal from source, signal flows from preamp to equalizer where the various frequencies within that signal can be tailored to one's preferences. I know of no other way, if you know something that Jaybo and I don't, then feel free to teach us. I just don't understand why anyone would not want to hear the source signal through the preamp first and then determine what frequencies you want to boost or decrease. This setup works and that is why I recommended it to Joey.
Cyclonicman, no negative vibe intended; I truly don't see what difference it can make. In most situations the voltage output from the source is more than high enough to drive an amp to it's maximum power, so the preamp is simply acting as an attenuator. Assuming the premap is linear, the equalizer gets the same waveform only differing in scale regardless of whether it's before or after the preamp.
If the preamp had a tape loop, isn't it common to place the equalizer in that loop? That way you can insert and remove its effects with a push of a button. Isn't the tape loop before the attenuator in the preamp? I think so.
Joey asked what would happen if the equalizer were in front of the preamp. No one answered his question, so I asked it again.
Okay Bob, I guess I was weirding out last night, my apologies to you. I understand what you are saying and in a tape loop, I am still not sure that the siganl is first presented to the preamp. Anyway, what I am saying is that when the setup has the input signal going to the preamp first, the equalizer will then have the actual input signal that would be directed to the power amp then to the speakers in it's pure form, which is the way it would be if there were no equalizer.
Definately after the preamp & then into the trash. Why would you want an equalizer? It will rob your system of its best abilities: detail, transparency, sparation, etc. and inject more distortion and noise. You know if you can eventually pull it off I would suggest a fairly new Mcintosh preamp with tone controls. It is designed that when its tone controls are set at 0db they are truly out of the signal path for critical listening. Another pre that comes to mind that accomplishes the same thing but is less expensive is the Halo P3 preamp.
Why would you want an equalizer?
To smooth room modes in the bass region. The B2496 may not be the most transparent EQ on the market (probably better than we imagine though), but its potential (to increase detail, imaging and soundstaging) outweighs any possible signal damage it may cause.
Tone controls are a joke compared to digital parameteric equalizers. In my book Joey is on the right track for superior sound.
The best place for an EQ would be after the digital out from a CD tranport. I think the Behringer 2496 EQ has a onboard DAC?. I know some people who use that kind of gear together with a mic. to apply some room correction. The correct way of doing this is.
1) have a someone messure the acoustic properties of you room.
2) adjust accordingly with bass traps etc.
3) measure agian
4) make minor adjustments to the trap etc.
5) use your EQ with mic and some pink/white etc noice to mesure your room
6) use your EQ to smooth out the last bits.
If possible don't boost frequencies only dampen freqensies.
Don't use cheap pro gear like Behringer pro gear or if you do modify it.
Pre amps like tact aleardy ahve some of those features build in.
That is not entirely true I think. Most pro gear is even more expensive then some audiophile brands up to a certain point. A lot of pro gear has to sound good and be able to take a beating. That is why you almost never see real pro's use Beheringer, the build quality is not that good and the sound qulity isn't that good to.
Mordante...I am not familiar with the entire line of Behringer equipment, but the DEQ 2496 is built as well as any audiophile gear, and sounds excellent. Any flaws are more than compensated by its ability to correct room effects.
Other pro sound equipment I use includes an Ashly electronic crossover. Circuitwise it resembles my old Marchand and Audio Control crossovers which are audiophile approved, and the construction is far better.
I also have a QSC power amp that I bought only to drive subwoofers. However the darned thing sounds fine full range, and I am using it that way in a second system.
I almost forgot my CarverPro ZR1600 power amps. Driving MG 1.6 speakers, they are every bit as good as the Channel Island D200 monoblocks which replaced them. The ZR1600s are now doing subwoofer duty.
Where you place the Behringer should in some way depend on what your source components are. If all your source components are digital (using digital outputs), then you can place the Behringer before the preamp, and if you have an external DAC, place the DAC between the Behringer and the preamp (or use the Behringer's built in DAC). In this way, you are not putting your digital sources through an A-D conversion. If you place the Behringer between preamp and amp, then all inputs sources will get an A-D, then a D-A conversion in the Behringer, since the unit does it's processing in the digital domain. If you have a mix of analog and digital sources, you might still be better off putting the Behringer before the preamp, since digital sources won't get the extra D-A and A-D conversions since you can run the digital out right into the Behringer. In either placememnt, all analog sources will be put through a A-D and D-A conversion. Keep in mind of course, that if you put the Behringer before the preamp to take advantage of direct digital sources, the Behringer must have enough inputs to handle all your sources.
Eldartford- I use Behringer equipment all the time when doing installs for venues, and gigs for a few bands(the cheapskate ones). I've been in them. Sorry to burst your bubble: I've yet to see one Burr-Brown(DAC/ADC/IC/transistor) Vishay, Caddock, Holco or Ohmite Gold(resistor), Black gate, auriCap, musiCap, V-cap, Solen, RelCap(capacitor), Schottky Diode, toroidal transformer, gold/rhodium plated oxygen-free copper(or even Switchraft) input or output on any of the pieces I've worked with. That goes for 95% of the other professional equipment I've dealt with in the last 30 years as well(except for maybe the Switchcraft parts). These components are found in virtually all of the higher-end audio pieces(I'm not referring to mega-buck units either). The pro manufacturers simply cannot build their gear with high performance parts, and sell it for 200 to $300.00(in the case of the 2496). OH- I forgot: It all sounds the same, right?
Eldartford- Have you ever used any Black Gates in anything? Some say salt, sugar, white flower, beef, MSG, sunlight, etc, etc are to be avoided. Do you? Burr-Brown is recognized in the industry as one of the best. My bubble is one of experimentation and experience with components, in audio equipment over the last 30 years(started by modding new Hafler amp kits for my customers), a love for the sound of live music (as a sound tech and musician), and an extensive(35 year) familiarity with professional equipment. Blah, blah, blah. I'll just enjoy this little bubble, and the Julian Hirschs(I don't ever listen to live music, but I have a pretty good idea what it sounds like") of the world can enjoy theirs. Just think of all the money I coulda saved if everything sounded the same to me too. DARN!!
Umm, Eldartford used to design electronics for nuclear submarines or something like that - he knows his stuff.
Also, I would like to get back on topic here. The Components again are as follows: Linn Kremlin Tuner, Jungson JA1 Preamp, Behringer 2496 EQ, Monster MPA-2250. Those components are 'set in stone' - I just wanna know if there is any MAJOR problems (like overloading circuits - like when you plug a line level device into a phono input-a big no-no). Will, for instance the pre-amp signal 'clip' if I insert the EQ between the preamp and power amp?
***PART 2 - UPDATE - Additional related Question***
For the Subwoofer. The Jungson doesn't have a second line out. My sub is an (Active) Super Nova. The way I plan to hook that up is take a second set of speaker wires from the amp outputs to the speaker-level inputs of the Sub. Is this right?
Joeylawn- I have no doubt that he knows a great deal about electronics as relates to Naval Warfare. How much of that experience translates into creating the illusion of live music, played by real musicians, in the original venue in the listening room? That has been, is now and always will be the goal of true high-end audio, though it's not everyone elses goal obviously. He made the statement that Behringer equipment(and/or other pro gear) is built using the same quality components as high-end audio equipment, which is completely wrong. That is what I challenged. I've been working with pro gear for 35 years, working on it for 30, and I know better.
Rodman99999 and Joeylawn36111...Just for accuracy...My work was on missile guidance systems (which just happened to be launched from subs) and my audio electronics experience goes back to about 1955. I didn't make audio my profession because my family likes to eat, but it has always been a hobby.
Rod....What is "quality" of a component like a resistor. Is it the "Vishay" label? I prefer to evaluate equipment by how it sounds in my system rather than by removing the cover and inventorying the component parts. And yes, I have components with Black Gate capacitors, but I see no evidence that they significantly alter performance.
Eldartford- Since you asked: I would have to define a quality component as one that doesn't impress it's own signature on the signal it's passing. Resistors are noise generators and bulk foils(like the Vishays) are some of the quietest. Before you scoff, read these:(http://www.ecircuitcenter.com/Circuits/Noise/Noise_Analysis/res_noise.htm)(http://en.wikipedia.org/wiki/Resistor). You'll note that the encyclopedia mentions how the TCR of the foil resistor is extremely low(the goal of any critical electronic circuit is low noise). I'm truly surprised that I even have to mention these facts, given your experience with military contracts. You should know how tightly the government controls the high quality of it's acquisitions via the mil-spec guidelines, Vishay being one of the approved component suppliers. The capacitors I mentioned in the other post were all designed to pass audio signals specifically, and likewise, are much more transparent than lesser quality caps. I wouldn't presume to tell someone that their preference in sounds is incorrect. What makes them happy in their listening environment is their business. I realize some can't hear the differences that quality components make in the audio chain. The mods(when needed) that I have affected in my own(and others') equipment has, with few exceptions, very obviouly yielded a more faithful reproduction of live musicians, playing real instruments, in the original acoustic(given a well engineered recording). This is the goal of high-end audio and most of it's designers/manufacturers. The musician friends that I like to invite over to audition and judge my system have always commented on the "you are there" presentation. That doesn't make my own listening more enjoyable than it already is, but the stroking still feels good!
Rodman99999...Once upon a time Mil Spec components were superior. Perhaps you are unaware that military equipment, at least that I am familiar with, today strives to use only commercial design parts which, because of the volume of production are often better and particularly more reliable than low production custom designs. Also, as a matter of policy, effort is devoted in the circuit design part of the job to make the circuit insensitive to variation of component parameters. We HAD to do it this way because even the most precise component will change characteristics when you fly it through a nuclear blast or, for satellites, through the Van Allen radiation belt.! But, after learning to design circuits this way it has become evident that there are other benefits. Important benefits. Save the taxpayer money!
I agree that capacitors in the signal path can affect sound quality. I have a few. But they don't have to be a particular brand and sprinkling them everywhere is idiotic. I have no reason to doubt that Vishay resistors generate measurable less noise, but my audio equipment exhibits no audible noise, so I don't think further reduction makes sense.
Most people that have purchased the better power purifiers thought their systems were quiet before they introduced the new piece. The general description of the difference is, "a blacker background", I suppose for a lack of better terminology. The same way a good purifier feeding an HDTV will yield a sharper picture. My system was dead quiet(as far as audible noise) before I plugged it into my Audio Magic Stealth XXX. The powerline grunge that the piece removed allowed a greater focus to images and a broader, deeper sound stage. There are just some things that you're not aware of until they're gone. There have been tweeks/mods that I've tried that were just so much snake oil. But then there have been a lot more that really surprised me. Upgrading whatever passive components are in the signal path, and finding the right tubes have always yielded worthwhile benefits(mainly greater transparency). Actually- I've saved money by not having to replace my older Cary power amps, but simply replacing a few components with higher quality pieces. Happy listening!!
Eldartford- A question completely off the audio subject(referring to "flying through a nuclear blast"): I thought anything with Metal Oxide Semiconductors would get fried if anywhere near a thermonuclear detonation. Have they gotten around that somehow? If so: Is there a way around the effects of an EMP bomb yet?
Rodman99999...You ask..."Is there a way around the effects of an EMP bomb yet?"
Yes, but if I told you all the details I would have to kill you :-)
Actually there are multiple techniques; some obvious like shielding, but lead is heavy (bad) so we use as little as possible. As I was a systems engineer the exact details of making ICs "rad-hard" are not my expertise, but the general idea is that the runs and other parts of the chip are larger (less miniaturized) than non-rad-hard parts, and they run slower (more current). Computer memory is the worst problem, but there are some types of memory that will not only remain operable after exposure but also will not lose data. That is, unless you are reading or writing when the blast hits, so data is stored multiple times to assure a good set will be available for use when the system recovers. Also, there is an ultra-fast radiation detector which turns off much of the circuitry power so it won't destroy itself with runaway turned-on transistors. Recent generations of guidance systems have included a star tracker which observes a preselected star once we are in space, and development of a solid state video chip (CCD) that is rad hard was not easy, and an old fashioned vacuum tube!!! vidicon which is inherently rad-hard was still used in systems that were otherwise very sophisticated.
The radiation which the system must tolerate is not primarily from the enemy, but rather from our own bombs going off in a massive retaliation. (Horrible thought).
Interestingly the spec rad levels for this military application are not as high as exists in the Van Allen belts (which is why satellites don't orbit at that altitude) or inside nuclear reactors, or for some spacecraft missions.
Finally, the underground nuclear tests that we used to do were not primarily to make sure the bomb went off (as most people assume) but rather to verify under real conditions the radiation hardening of various military electronics. We know the stuff works. And so do the Ruskies, which is the whole point of the exercise.