Many small resistors isn't what was posted. And wasn't in amp design GM. Apples and oranges.
Hmm, can't comment WRT resistor banks Vs a single large resistor in amp design being audible, but at the speaker power level, resistors have the same type of thermal amplitude modulation distortion as a driver VC, 'crushing' dynamics, so can make an audible difference in some cases and why I use many small resistors instead of one big one same for the same reason I would use multiple smaller drivers Vs just one big one in a high efficiency, wide BW app. If nothing else, the lower the heat dissipation/'clamping' required, the less critical the resistor material composition, ergo can be much less expensive if you discount the extra labor of assembling it.
Must get down to level 7 before the firestorm hits.......
GM
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
Many small resistors isn't what was posted. And wasn't in amp design GM. Apples and oranges.
Your neighbors called. They like your music.
Hi GM !!
Nice to be able to talk to you. How about a whole other area of thinking about multiple resistors in crossovers, etc., that perhaps we should consider. ( My own idea, and I speak and write very differently than many do, so bear with me.)
First, allow me to tell you my speaker crossover experience from two weeks ago !! It was really neat. I have an old pair of KLH 5s which has its internal wire optimized - replaced ( from the crossover the the drivers ), and I have placed the crossover OUTSIDE of the speaker enclosure. The KLH 5 crossover uses a 15 Ohm 5 Watt series padding resistor on the two four inch midrange drivers. ( Same drivers as in the old KLH radio, a nice smooth driver ).
First, I replaced the 15 Ohm stock resistor with a 10 Watt non inductive "yuppie - audio quality " resistor. It was a LITTLE bit better, cleaner - yes, but really not worth the effort nor the cost. Next, I replaced the 15 Ohm Non Inductive with two Dayton 30 Ohm 10 Watt non inductive resistors, closely matched. Holey COW and Jumping Jimmy. My reference cut, Chet Atkins and Jerry Reed "Sneakin' Around" portrayed their two voices in a manner, and at a level, I had never heard on any system I have played it on over the last ten years. ( I am referring to improvements in tone, spatially, and in fine resolution ).
The following is SPECULATION on my part, as to what was happening. GM, I wanna tell you , I think its more than just "thermal amplitude modulation " alone. I want to propose to you one additional mechanism. I believe an INCH of bad wire, in a critical place, can degrade, maybe even ruin, the musical experience we seek from our systems. You mentioned above..... "crushing dynamics".... YES !!! that is where I am going.
Has anyone ever addressed the PUny lead out wire on a resistor, ........ is it 20 or 22 AWG ? Is it steel or copper? How come we try to run the whole audio signal ( the whole orchestra ) though an inch ( total ) of CRUMMY PUny wire, going into and out of that crossover's resistor ?? THAT mechanism is robbing us of some of the good we would derive, had it been properly addressed I say !! Just going from one to two resistors, in a series circuit to the driver, offers a performance improvement. WE have two wire paths now. Instantaneous PEAK music signals are no longer being clipped. The amplifier couples to the driver's voice coil better.
The speaker, assuming its in a good system ( this can be a BIG assumption ) plays at a higher performance level - and it is audible. It is also important to closely match the two paralleled resistors, to obtain optimum benefit. That way, one does not, in any way possibly "buck" the other.
Regarding my contention of "an inch of bad wire in a critical place can ruin the musical experience", I had one other UNUSUAL experience to share, in addition to the KLH 5 speaker crossover. It was instructive. Three years ago I took a EICO HF-81 ( P-P 6BQ5 receiver ) and replaced a 5/8ths inch wire run, from the plate of the input tube, to the grid of the phase splitter ( across a 9 pin miniature tube socket ). I changed this short span of wire from stock ( bell wire ) to one, than two, then three runs of Kimber TCSS wire, and listened. In each case, the sound was (a) different and (b) better.
Of course, this was a DIRECT COUPLE, so, the whole orchestra was going through that 5/8ths inch span. Anyway, GM, my subjective listening experiments made me very AWARE of the effect or wire, internally, in key places. So, I am suggesting using two resistors, in series, instead of one...two wire paths !!
We are thinking in terms of keeping the music intact, in terms of dynamic performance, and preserving the instantaneous peak performance of music. If it is clearly audible on a KLH 5 and on a 12AX7 in my EICO HF-81, running at 1 mA., (which is also a CAT preamp !!). Might it also apply to optimally powering our drivers ALTEC ?? 'You bet cha'. Every Altec compression driver gets padded down to the lower efficiency woofer, usually resistively. Lets smell the roses before we die !!
Jeff
Our doubts are traitors, And make us lose the good we oft might win. By fearing to attempt. William Shakespeare, "Measure for Measure", Act 1 scene 4.
Last edited by LowOhms; January 13th, 2013 at 04:05 PM.
Simple, to find out what others know, and learn from others' experiences. I am smart enough to figure out who is responding and GUESS at their experience level, attitude, and basic honesty.
Its sorta fun to do.
Read between the lines. I already know about a bunch of new people on this Forum that I have never met before !! No doubt, and vice - versa. All of these people I like, and are very nice folks. Cheers.
So far, SD-50 in post #13 has come forward with his " by ear " ALTEC 6 dB actual experience. Likely more such users exist. I hope to learn. GM talked about first order users "in the good ole days ".
A nice discussion might be use of SERIES passive 6 dB crossovers, who is doing that? I will try it when all parts are assembled. Dominique liked SERIES " it was a chock ( shock ) when he heard it " versus his Hiraga-style crossover.
Jeff
Last edited by LowOhms; January 13th, 2013 at 04:31 PM.
Your neighbors called. They like your music.
Agreed ! I was just trying to be diplomatic OG,as this thread was his first post on this board... I took it as his opinion and not fact..But will keep an eye on it. If the OP is here to just stir the pot ? I will deal with it accordingly.
LowOhms, I suggest you to tone it down..When you go back and forth with a few members the discussion can get heated and that is not what we want here.We are all here to gain knowledge and to help one another not to start confrontations on ones opinions..But most of all we are here because we all enjoy our Altec's.Once the thread moves from that it becomes Off-Topic.A general audio forum would probably be better for your question, as we are a specific forum for Altec enthusiasts.However you can start a thread on what you like, but we ask that you post (OT: ) at the start of the title of your thread.
LowOhms.
a.k.a. drlowmu elsewhere?
Opinion is only as valid as its verifiable supporting evidence.
Yes, this is Dr. LowMu elsewhere. I tried to be a bit diplomatic earlier but Jeff fails to see that others don't agree with his methodology. He's on a self proclaimed hiatus from his usual posting spot and can't stop putting his ideas out there, in this case here. In the past Jeff has written that he can hear the difference between a cathode resistor of 10 ohms difference. I asked whether that was hot or cold without a response. His posts are inflammatory and by the tone of his first question I would say that he's trolling. His experience goes way beyond most posters and if he's asking about Altec, he's owned them before or has personal experience with a variety of drivers. His current favourite speakers are by a friend of his that uses 604"s.
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