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Perreaux SHX-1 lovers - Page 3

post #31 of 108
but still, anyone know the answers to my questions #2 & #3? i really want to know.
Yes, see my response above.
post #32 of 108
just wanted to keep those interested updated...

i have .3 revision & wanted to see if they had the .5's in...the lady had no idea what i was talking about so eventually transfered me to sales...sales knew what i was talking about but then said that they were not doing the .3 to .5 mod (slight design change to fix volume knob scraping) & that it's something that has only been done to the new models being sold (before gettin' to AA perhaps)...i asked if they were not doing the mod then who would?...would i need to send it to perreaux?...you guys are "the" authorized u.s. dealer etc etc....they just kept saying that they weren't offering the mod & it was only for new models...so i read off what sov posted from clinton...then the guy went for a manager ...so they figured out the easiest thing for both of us is for me to send back my unit & they'll send me one of the already upgraded models...

anyhow...looks like it all worked out in the end & i'm glad audio advisor's remained helpful (albeit in a roundabout way) throughout this entire affair...

i'll probably post a pic or two of the .5 when it arrives...
post #33 of 108
Yes, see my response above.
yes, i did read it entirely. thanks for the response. however, you didn't answer those two questions. you said i "may or may not" hear buzzing at louder volumes--that does not mean you did hear buzzing in your unit at full volume with no inputs. as for the tape out deal, i don't have a normal home-audio setup. but the problem isn't me not feeding it enough juice--it's that it does not amplify the signal as much as i thought it should.

but i just called Chris at Audio Advisor and he says the mods shouldn't change the performance of the unit, and that it shouldn't change the gain.

also, he said that i was testing the unit wrong, and i should use a "shorting plug." now i understand. anyway... the unit is pretty much dead quiet.

but i still think that the gain is low.... what you guys think? i mean, i've used plenty amps before, and this unit is the lowest gain i've had, by far. though according to AA, the position of the volume knob does not alter performance (doesn't increase noise nor distortion), so he said i can crank it up without worries. this is new to me, since most my equipment gets notecably noisier with higher volumes.
post #34 of 108
Thread Starter 
here I og Orpheus:
2. No noise, wihtout any hooked on the jacks, but this is very common in headamps and hi gain amps, just hook it, ground....

3. No at 9:00 to 11:00 it the higher volume I used on it, at 11:00 with the CD3000, you will be deaf, this is hooked directly to my source, if you use the preamp in the middle, and control the volume with the preamp, I don't know, but htis a very unusual way of connecting a headamp, the input for the Perreaux as many non-pro headamps, is line out, not pre out....I don't know but uusally in Pro audio the headamps are more powerful and accept pre out and bigger inputs....
post #35 of 108
oh, okay. didn't know you guys usually hooked up the headamps before the preamp--i mean, isn't that what a preamp is?--a fancy volume control? i'ts meant to give the best level of input to whatever amps you use it with, uncluding headamps--that's what i think anyway.

but that reminds me, this unit has a pair of outputs. are these outputs paralleled to the inputs?--or does it go through some of the amplification circuitry?
post #36 of 108
Thread Starter 
They are parallel wired, so you can use any for the input and from the other set, to the input of the preamp, and no, the pream is not only a volume control, the pream has a gain stage also, that is unnecessary to use for the headamp to operate, as it has its own gain stage inside, unless the pre, was a passive one, that is in fact an spepped attenuator, or a volume control only....but mainly they have a gain stage also....
post #37 of 108
well, yes... but what i meant was that this "gain stage" is still a fancy volume control. it basically gives you more volume to work with.

you see, many amps/headamps need a certain amount of input to reach maximum volume... and a lot of the times your source does not have enough output. so, you need a preamp. it really has nothing to do with with what amps/headamps have "gain stages" or whatever. no matter the internal construction of an amp, it still needs a certain amount of input to reach maximum volume, and that's what a preamp is all about: volume control.

for instance, what if my source only outputs a small amount of signal?--then if i attached my sxh1 to it directly, it would never be loud enough. so, you stick in this preamp between the two, then you can match the volumes correctly. that is why you're supposed to attach units that need a certain amount of signal, like power amps and headphone amps, to the outputs of your preamp.

of course, if your CD player is loud enough, you can bypass the preamp completely. but the entire purpose of a preamp is to select from different inputs and to output the optimum level of signal to amps/headamps. so, to summarize, the headamp is attached to the outputs of your preamp. if anything, at least you can use your preamp to switch among sources.

anyway, at my studio wiring is MUCH more complicated than this. no simple source > preamp > headamp stuff. we're talking 200ft of cable, 2-4 trips to the patch bay, even passes through maybe 3-4 "preamps" before a signal even gets to the amps. signals are split zillions of times, recombined, mutated, or even....... arrives safely! at the destination: my Perreaux SXH1--a damn fine headamp.
post #38 of 108
Actually, the main reason for a preamp is to buffer (provide current and low impedance) to drive an amplifier. Hence the name. A preamp can have an input and output, nothing else, and still deserve the name.

Most home audio preamps have "tape" or "line" outputs which include buffer amplifiers to drive tape recorders and other devices. They also have the main output(s) which also pass through the volume control.

I use a passive unit. Source selector, tape outs, gain and balance controls, mute, and main outputs. It is a common misnomer to call it a "passive preamp." Better to call it a "passive control unit."

My SCD-XA777ES and Vendetta SCP-2A phono preamp drive the amps directly through this passive. I have enough gain, but just barely (when I use a high feedback setting on the amps).

The best way to drive a headphone amp is to tap into the signal at the earliest possible point after the source selector. This is usually the tape outputs of a preamp or passive unit.

Note that the cables that feed a headphone amp may (in the absence of buffer stages) add capacitance to the other cables in parallel, particularly those to the power amplifiers. In my setup, the headphone amp cables loads the source in parallel with the volume control pot and main output cables. Fortunately, the sound quality is fine, because I use low-capacitance Cardas cables and low output impedance sources. But, recently, we tried Alex Peychev's SACD1000 with its high impedance output (300 or 600 ohms, I forget), and it did not sound its best at all. Still, one could tell that the midrange of his unit is marvelously realistic. Bass and Treble were weak and soft.
post #39 of 108
Thread Starter 
Orpheus, you do not need a preamp with the Perreaux, just try it from a source directly and you will see that there is no problems, most sources are able ot drive headphone amps to a satisfactory level, in other words, the headamps, all of them, AFAIK, are designed to be feed by a line level sources, not from a preamp out.....
post #40 of 108
um, no.... preamp out IS "line-level." and so are source outputs--they are all "line-level." doesn't mean anything. the question is whether the signal is loud enough for the perreaux... and yes, you are right, most CD players are quite hot enough. but no, headphone amps are not necessarily "made" for direct source input... but they do mostly work fine straight from the source as you have said.

and if you're wondering why i don't hookup my amps directly to the source... well, it has mostly to do with aesthetics and the working environment, but also my CD players has such a hot output that it fries many of the headamps out there. i even have to use attenuators going into my preamp. and it's easier to use the preamp as a control device--also, i like having fun with tube preamps.

anyway... believe me, i know how to wire stuff up. i don't think anyone on this board has a more complicated home-based system than me...

but from your responses, i take it no one has gain problems from this headamp then. no biggie... it probably has more to do with my own preamp, which is a bit quirky.
The best way to drive a headphone amp is to tap into the signal at the earliest possible point after the source selector. This is usually the tape outputs of a preamp or passive unit.
i disagree. it is only practical to do that in a very simple system. yes, you are right, technically what you say about the function of a preamp is correct... but in reality, that's not what you use preamps for: they provide source selection, and volume control, basically. and almost everything sounds better straight from the source, but that's not how you necessarily should connect things. you usually do need some sort of volume control and source selection, hence the consumer preamp. here i use a mixing board though... and a separate audiophile tube preamp for monitor control--PURELY for fun.
post #41 of 108

The stuff you are saying is technically not right.

"CD players" may have high sensitivity, but none of them will "fry" a headphone amp. And, the inputs AND outputs of a preamp are all considered "line level."

Attenuating to achieve the control of volume is done in most headphone amps, so a preamp is not needed; if there is one, it is best to bypass its gain stage and potentiometer, such as using the tape outputs. So, yes, most headphone amps are designed to work directly from sources. You can use a preamp, but you can use an infinite number of buffer amps too... it isn't necessary or even how it was designed to be used.

At least for myself, I have installed and consulted on tons of home and some pro audio systems. Instead of arguing and nitpicking with us, you should seek to understand us... or just keep your personal non-standard ideas to yourself. ;^) Your system sounds like a hodge podge... but remember, this thread isn't just for you. We are trying to put information that is generally correct, not just cater to you.

Yes, it does sound best to go direct from a source to a headphone amp. Second best sound quality is to take the tape out of a control amp or passive; this also puts the source selector in the circuit for better convenience.

You connecting it to the preamp output is indeed non-standard and non-ideal. All you need or want is one volume control; best to be the one in the headphone amp itself.

Since you have some sort of non-standard system that you are playing with, then you are on your own. ;^)

The things one needs to grasp are sensitivity (voltage), ability to drive a load (output impedance), and load (input impedance). That, and keeping the signal path simple and minimal. From there, all else flows....
post #42 of 108
"CD players" may have high sensitivity, but none of them will "fry" a headphone amp.
i didn't mean literally. the outputs on my cd player are hot enough that they clip on many headphone amps. okay? sounds like a distortion guitar when it gets loud. that's what i mean.
And, the inputs AND outputs of a preamp are all considered "line level."
that's EXACTLY what i said. it was sovkiller that said otherwise.
Instead of arguing and nitpicking with us, you should seek to understand us... or just keep your personal non-standard ideas to yourself.
i don't mean to "nitpick" anything with you. i know that you know what a preamp is. i am just saying that preamps are made exactly for the purpose to interface your amplification gear, including headamps, to your source. that is their job. if you insist to plug in your headamp before the preamp, that's fine... it'll sound better that way anyway, as you pointed out. but as for how you're "supposed" to hook it all up, the preamp is intended to go between any of your amp gear and your source. again, it provides source selection and volume control. just the fact that your headamps provide a volume control built-in doesn't mean that you don't need a preamp, though you probably don't, as you have said.

anyway, i don't want to argue with you. i acknowledge that if your system permits, direct connection between your source and your headamp is best. but you are wrong about the usage of a preamp--i know you know what it does, but you're not using it the way it's intended. and that's all i was trying to say.
post #43 of 108
Thread Starter 
Orpheus: maybe you understand that, but I never say that the pre out is not a line out level, I just called "pre out" and source "line level" to differentiate them, though technically they may have the same behavior, IMO they are not, some preamps has also tone controls and tone networks, and even when by-passable, they interfere in the signal path, and make it even longer unnecessarily, and add a volume control that you already have...look at this way, if you get a receiver, or an integrated amp, where do you hook it, at the pre out? No right, same as a headamp....it is like an "integrated amp to drive headphones".....
post #44 of 108

No, we disagree. I have seen almost no headphone amps that have no volume control. I have seen almost no headphone amp owners who put their preamp with its volume control in front of the headphone amp. You are the anomaly here by putting two volume controls in series. That is not how the units were designed.

Nobody puts a tape recorder on the pre-outs. They use the tape out (unless they are using a non-standard control unit that lacks them). This is also where a headphone amp goes.

As for the other topics, if you would be more precise in future, we can avoid a lot of back and forth.
post #45 of 108
A headphone amplifier is basically a integrated amplifier if you look at it- it contains a preamp and amplifier section in one unit. True, most only have one source input, but that input coupled with a volume control constitutes a "preamp." I can understand, Orpheus, that your situation likely warrants you to have to connect your head amp to your preamp's outputs because your source is connected to your preamp which I am concluding is part of a speaker system. However, connecting the head amp to your preamp's pre-outs is not the way you should do it where you should connect it to your Tape output for the reasons Stoney has outlined. If it has no tape output then obviously you have no choice. The "problem" with using the "pre-outs" is, as Stoney said, the signal has to be routed through another volume control and thereby possibly (most likely) further degrading the signal. The vast majority of people connect their source directly to their head amp. It is true that preamps are an "interface for your amplification gear" as you described but let's not confuse what a headphone amp is: it is an integrated amplifier that already has a preamp, not just an amplifier.
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