Alk es - networks coming soon

[D-MAN]

Shawn, I'm using a Mac MC300.

Al, just rattling your cage a bit!

BTW, my custom ALK-ES's without fuses (OMG!) are doing JUST FINE!

Dana

[mark1101]

This is interesting.

What would be good is if someone would just replace the fuse on 1 speaker with a wire and report back on a "mono" sound test using the balance control from L to R.

Basically, can you hear a difference, and what IS the difference in sound?

If you have Khorns with traditional fusing you could just pop the fuse out and put in a piece of wire. The nice thing is that since there are 2 fuses you can decide if the change in sound is in the LF or HF section by testing each independently.

I think what some of the earlier posts are saying is that it depends on what amp you are using as to what differences there may be.

I would just like to know if you can hear a difference with ANY amp.

All of my aftermarket network replacements have no fuses, and I'm careful. But I left the fuses in my Khorns just because they were there when I got them.

[sfogg]

Dana,

" I'm using a Mac MC300."

According to Roger Russell's site that amp has a damping factor of 40. Assuming that is into an 8 ohm load (normally how it is rated) that means the amps output impedance is 0.2 ohm. ( 8/0.2 = 40 )

Into the assumed 6 ohm load if the amps output impedance stays the same (might not with the autoformer on that thing) its damping factor is 30. (6 / 0.2 = 30)

Add another 0.25 ohm of impedance to the circuit and the damping factor of the amp into the same 6 ohm load is now 13.6 (6 / 0.45 = 13.6)

Mark,

"What would be good is if someone would just replace the fuse on 1 speaker with a wire and report back on a "mono" sound test using the balance control from L to R."

The problem there is that it isn't blind. If someone thinks they are going to hear a difference they may simply from the power of suggestion. It influences peoples 'hearing' far more then most give it credit for. This is also well known and easy to demonstrate.

"I would just like to know if you can hear a difference with ANY amp."

So would I. But I'd rather have the answer to that be far more controlled so the possibility of imagined differences is accounted for.

Shawn

[D-MAN]

Shawn, I don't know what to make of that, the speaker/network is a reactive load and is constantly changing its overall impedance. Add to that the vagaries of the autoformer, and who knows?

I once demoed a stock ES with the fuse in place and then jubped around the fuse with a piece of short 12 ga. speaker wire for a friend who used to sell speakers for a living.

He agreed with me - took about 1 second for him to make up his mind.

The difference is in "clarity" and how the soundstage is "presented". One is preferred over the other, that's for sure. I use the term "clarity" in a manner which describes a degree of openness and precision compared to a constrained or congested presentation.

This experiment convinced me to permanently jumper around the fuse holder with good copper speaker wire. But I don't want to solder on something I just paid $900 bucks for!

The next pair of ES xovers I ordered, I specifically had Al leave out the fuse completely. As far as gaining some form of driver protection, as I said earlier, I've owned more expensive speakers, and none of them had fuses.

Here's a quote from PWK concerning fuses:

DM

[sfogg]

"I once demoed a stock ES with the fuse in place and then jubped around the fuse with a piece of short 12 ga. speaker wire for a friend who used to sell speakers for a living.

He agreed with me - took about 1 second for him to make up his mind."

Anything that 'took about 1 second' is not based on any real listening but sets off plenty of warning lights to me.

Like I have suggested to you before do some demos like this and act just like you changed something but don't really change anything.

You will find people that 'hear' a difference when in reality there is none. It will happen far more often then you think. Do it enough and you will also see how easily it is for you to influence the responses you will get in however you want to get them.

You don't know the power of the dark side! (suggestion)

If you want to avoid the possibilities of Jedi Mind tricks influencing your 'experiments' you need a way to *know* when someone is being delusional. Controlled listening tests are how you do that. If you weren't on the wrong coast I'd setup a double blind ABX test for you of fuse in/out of the circuit. Pass that test and you would prove to me you are heading a difference.

Shawn

[Al Klappenberger]

Dana,

I guess I should admit to something: I really don't care much about the fuse one way or the other, I just enjoyed yanking your chain about it! []

Al K.

[D-MAN]

Shawn, if you have fuses, try it for yourself. You've got Khorns, right?

{edit} Shawn, if I remember correctly, you're running an active crossover, so nevermind.

Al, I suspected as much, I could sense the mischievous delight in your emails!

Dana

[Deang]

Shawn -- those figures are interesting. If we were doing these comparisons between amps with relatively high damping factors then I would think it would be close to impossible to hear a difference. But in this particular example, I can see where it might be pretty easy to hear it -- there is a pretty big difference between a damping factor of 13 and 40. I mean, that's like comparing the bass of a push-pull tube amp with moderate feedback to the bass of a Dynaco 400 (damping factor of 50 I believe).

[sfogg]

Dana,

" if you have fuses, try it for yourself."

I don't have fuses, I am triamping. Only thing between my amps and the drivers is speaker wire.

"You've got Khorns, right?"

Nope.

If they do make a difference it would likely be system dependant on the amp and speakers used.

And all the above is ignoring the much bigger problem of my trying the test for you. If I passed an ABX then that is easy... it demonstrates I heard a difference and therefor that at least in one case there is a difference.

If, however, I failed the test we haven't learned much of anything. You will likely claim I'm deaf. And it still doesn't really say anything about if you are correct in what you claim to hear or not. (I can't prove a negative, only a positive)

That is why those making the claims are the ones that need to be tested to back it up.

Shawn

[jwc]

This thread is crackin' me up. There is already 4 pages of posts and the guy doesn't even have his networks yet.

I must say I'm anxious to see some pics.

I made AL's ESN700's with the fuses. I really thought the speakers I placed them in would be a little abused with power. So far they are playing at the "moderate" levels of somewhere aroung 80dB I would guess. Maybe I should pull the fuses and try and notice a difference.

[mark1101]

Wanna laugh some more?

Do you think that a Buss brand fuse sounds different than some of the other brands? Do all fuses sound the same? Do they all measure the same?

If I bought my fuses at Walmart, would they sound inferior?

If I replaced the fuse with a 2" piece of 12ga. monster cable would it sound better than with 14ga zip wire?

Where does it end?

I bet if I open the windows in my listening room it will make me want a new amp or anew set of networks.

[BEC]

Shawn,

This looks pretty simple to me as far as the effect. Isn't this added fuse just the same as a slightly larger DCR in the inductor? The inductor on the crossover I measured has a DCR of about 0.37 and the fuse has a DCR of about 0.26. What changes with frequency is the Inductive Reactance which increases with frequency and adds to the DCR. Therefore, the effect of the fuse would be greater at lowest frequencies and less at higher frequencies. At DC the effect of the fuse holder on impedance would be about 70 percent as much as impedance of the inductor. At 120 hz, the effect of the fuse would be about 14 percent as much as the impedance of the inductor.

Looks like then we can set this thing up as a series voltage divider. Assume woofer at 6 ohms, inductor at 1.7 ohms and fuse holder at 0.25 ohms with 120 hz signal applied. Lets make the signal input to the crossover 1 VRMS. That gives us 0.755 VRMS applied to the woofer. The rest is lost in the fuse and inductor.

Now without the fuse holder the woofer is still 6 ohms the inductor is 1.7 ohms. With 1 VRMS applied we get 0.78 volts applied to the woofer.

So the question would become "Can Dana hear the difference between 0.755 VRMS and 0.78 VRMS applied to the woofer?"

I believe this translates to a difference of about 0.28 db at 120 hz. The difference would be more at lower frequencies and less at higher frequencies.

Bob Crites

[sfogg]

Dean,

This is a good point. If you start out with a huge damping factor after adding the resistance into the circuit that will of course drop damping factor down greatly. But where you end up might be 'good enough' that it makes no real difference.

Conversely, if you start out with a really poor damping factor adding a small amount of resistance likely isn't going to make it all that much worse.

In the middle when you are around perhaps where the audility of damping factor may/may not be an influence..... perhaps it has more of an effect if the additional resistance throws you over that threshold. If there really even is any sort of hard/fast threshold for audibility.

I looked at one quick chart (didn't check that math on it) that said basically from the difference in damping factor from 50 to 10 would result in FR difference (from the interaction I mentioned earlier) of a little above 0.3dB. That chart was simplified as it ignored the reality of drivers impedances changing with frequency so the amount of a dB difference and at what frequency that difference occured would very much depend upon the speaker.

0.3dB if it is over a very wide band is considered roughly the lower limit of audibility WRT level differences. If that is occuring at only narrow band of frequencies it takes a greater SPL difference for it to be audible then if the level difference was broad band. So IOW by itself that FR deviation is right at the fringes of audibility. It would take a skilled/trained listener to have a chance of hearing it and most would not be able to. No way in the world someone is going to hear it 'in one second' but it is audible to some.

If the fuses impedance increases as it heats (which it almost certainly does...) its effects on damping factor/FR interaction is going to grow larger which could make the chance of it being audible larger too.

So where does that leave us?

Same place as always.... with no easy answers.

Do I think there are dramatic changes in sound as claimed here? No.

Do I think there might be some 'power of suggestion' influences here? Yes.

Do I think that there is a possibility it might make enough of a difference to be audible? Yes.

Do I think there should be controlled testing to determine if those that think they hear it actually do? Yes.

Shawn

PS.

"But in this particular example, I can see where it might be pretty easy to hear it -- there is a pretty big difference between a damping factor of 13 and 40. I mean, that's like comparing the bass of a push-pull tube amp with moderate feedback to the bass of a Dynaco 400 (damping factor of 50 I believe)."

Remember though that the difference in bass between those two may well in fact be do to factors other then just damping factor. Simple FR for example.

[Hardhead]

It's interesting that so many posters are telling each other what another person can and can't hear. It would seem superfluous ON AN AUDIO FORUM to say that no one perceives and interprets sound exactly the same as anyone else, that no audio system is exactly the same as anyone else's, and that no room acoustics are exactly the same as any other room's, yet we continually ignore those hard, unchangeable facts.

The simple fact is that no one can say what anyone else can or can't hear. Another simple fact is that audio systems with high resolution can reveal subtlties that a system of lesser resolution simply can't. We all like to think our systems are as revealing as they can possibly be, but they aren't. Yet another simple and somewhat regrettable fact is that the vast majority of us are middle-aged, or older, males whose hearing is continuing to decline rapidly, whether or not we notice or want to admit it. Our inability to hear something doesn't mean that someone else--even another middle-aged male--can't hear it. You simply may be able to hear something that I can't, and neither my inability to hear it, nor my unwillingness to consider that you can hear it, will change what you hear.

To make statements about what a different person with different hearing abilities using a different audio system in a different room can or can't hear is patently ridiculous. I can't know what you hear--it isn't possible--and vice versa. If you say you can hear something, I ought to believe you can, even if I can't hear it. Conversely, my inability to hear it says nothing--nor can it say anything--about what you hear. And vice versa.

I suspect these statements in so many forum threads in the past, present, and future about what other people can or can't hear ultimately say more about our own insecurities than they say about audio.

[D-MAN]

Hey, Bob!

I've designed a dual 15" corner horn specifically for your drivers! That's 4 drivers just for my prototype pair!

Shouldn't you want to NOT piss me off?!

Dana

[mark1101]

If I had to bet on it, I would bet that Dana is right. A fuse could make an audible difference as has been suggested.

PWK "more or less" said it himself in the Dope (that was removed). He makes his business and sensibility case, then comes clean that it is simply best without a fuse, without actually saying it sounds better without it. I'm sure he didn't want to increase warranty costs on woofers, but in the end was being honest about the sound.

Just guessing though.

[sfogg]

Bob,

"Isn't this added fuse just the same as a slightly larger DCR in the inductor?"

Kinda sort but not exactly as the fuse itself likely isn't going to alter its impedance over frequency like the coil will.

"Looks like then we can set this thing up as a series voltage divider."

Yes, that is where the FR interactions come into play.

Two comment on your numbers though.

A) You are assuming a source(amp) feeding the crossover/speaker with zero impedance. That doesn't exist. If the numbers for Dana's amp are accurate his amp has 0.2 ohms of output impedance. We will have to assume that is constant with frequency but it might not be. Add the amps impedance to your numbers too.

You are assuming the load is a constant 6 ohms over frequency. By itself it very likely isn't. We really don't know what the impedance of his bass horns are doing. The greater the loads impedance swings the greater the differences in FR you will see if your source has a higher impedance.

Shawn

[sfogg]

" I can't know what you hear--it isn't possible--and vice versa. "

When my neighbor three doors down has Strawberry jam on his morning toast my system sounds better then the days he uses Grape Preserves......

Shawn

[BEC]

I would say that I don't really like fuses in speaker circuits either. Audibility of the fuse being in there or not is up for argument, but the fact that it can only degrade audio performance is not up for argument. Never heard anyone claim it makes the speaker sound better.

Bob Crites

[Al Klappenberger]

Guys,

What Bob point out is why I don't beleive you can hear the fuse unless you THINK you hear it. The power of suggestion is EXTREMELY powerfull! Btw: Bob left out a few other sources of DCR, that is the 4 Ohms or so of the wire in the voice coil and that of the speaker cables. Changes on the order of .2 Ohms in a system that has a total of about 5 Ohms is quite insignificant. At least the DCR of the fuse does not de-Q the inductor the way the same amout of resistance associated with a coil wound of smaller wire would. That I think you WOULD hear.

Al K.