6 dB per Octave Passive Crossovers

6 dB per Octave A7 Passive Crossovers :

Hello,

I recently joined this Forum and have been getting prompts, every time I log in, to make my first post and introduce myself. O.K. !! My name is Jeff, I live in a small college town with rolling farmland all around, fifty miles outside of Kansas City, Missouri. I am a life-long audio and music enthusiast.

Sixty years ago, very late one night, my Father sneaked a brand new Altec 604B into our home, while my Mom was sleeping. Dad sawed a hole in Mom's Laundry Room’s wall, in our finished basement, and mounted the 604B to "fire" into our family’s Recreation Room.

We had stereo. Dad had a second ALTEC coaxial in a Karlson enclosure, and so, I was weaned at a tender age on home audio and music. This was how my Dad handled “WAF” in the early 1950’s.

Fast forward, it is 2013, ( Happy New Year ), and I am about to put together my first Altec A7 system, for my home use, powered by low Watt directly heated triode amps, ( you know - 2A3s ). I sense this ALTEC community is vast, so I would like to ask for some help from those who are ( or have ) used 6 dB per octave crossovers.

So far, I have found two ALTEC write ups which gave a good run down, one from GM and one from Larry D. Moore, a gentleman in Ohio who runs “ UltraFi “.

GM posted this, on 4-29-2003 :

"The 416 has fairly benign breakup modes and in the good ol' days a lot of the guys ran them straight up, with just a shunt resistor across the HF capped off at 1.8kHz for the 811 and 1.2kHz for the 511 IIRC. Experiment with a series resistor to shelve it down some and you're done. If you find the breakup modes annoying, then roll it off with a 3mH big wire inductor, which may require swapping out the series resistor with something smaller."

GM was asked :

"I don't quite follow the "shunt resistor" idea. Can you explain a bit more to a novice?" tdc

GM responded :

"A shunt is any device wired in parallel to a load, so in this case it gets wired in parallel to the driver's VC. Some folks call them damping resistors. Here it serves two purposes, one to damp the horn, and with the series resistor shelves the horn's entire BW to whatever sounds best in your room. If the highs are too rolled off for you, put a cap in parallel with the series resistor to taste to keep the extreme highs from being attenuated."

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Larry D. Moore, a decade or so ago, preferred 16 Ohm 515B woofers, or 416-8Bs in his A7s. He liked either no inductor or a 2 mHY low DCR air core foil inductor. He preferred a 511B horn with a 802D and 16 Ohm early aluminum diaphragms . No bug screens, no vanes in the 511B .

He rolled off the tweeter with a 20 uF film cap, ( seems sorta large to me ) and padded the tweeter's output with 8 to 16 Ohms of series resistance, ( Mills MRA-12) bypassed with a 0.5 uF to 2 uF film cap, value selected by ear, to regain some of the highs. He used SET amps. If anyone wants to see Larry’s entire A7 write-up in UltraFiTimes, Issue 6, email me and I will promptly send it as an attachment.

OK, I bet there is some of you on this Forum who use simple first order passive crossovers for home HIFI, and maybe even SET amps. What can you share with us, as to what you ended up doing, and what you tried that worked best ?? Please don’t let the many Forum members, with huge listening rooms, solid state amps and active equalizers scare you off !! Allow your minority voice to be heard.

I pick-up 825 plywood enclosures, later this month. Hooray . ‘Have on-hand ALTEC 515B woofers, 802 tweeters , 511B horns, and parts to build a home brew crossover. The tweeters go to GPA soon - for a redo, remag, and GPA's “low powered - critical listening” 16 Ohms diaphragms installed. I am considering configuring a passive series crossover, rather than build a typical passive parallel. Yes I will brace the enclosures, and add smallish wings, similar to Per Hasling’s.

Can I gain from your expert arcane experiences ?? I am a BIG believer in KISS and not messing much with the signal. My amps are KISS, two tubes direct coupled and a Magnequest output transformer.

Treat me gently, this is my first post !! Isn’t audio fun, and music sublime ?? Thanks in advance.

Jeff

20 is pretty big ie 500 Hz at 16 ohms.

The bypass cap does not 'regain' highs. It essentially is an EQ circuit, the result is to lower the mids relatively. The cap conducts across the resistor at higher frequencies. You can't consider components like that- you must view the whole circuit.

There are a few who advocate 6 db/octave, bear in mind it lowers power handling.

But best is still active crossovers and separate amps. Just my 2 cents.

I've played around with very similar components for a few years...

I ended up going active, as OG above mentions...

when running the VOTTs biamped
I liked a push pull 6BQ5 I came across for not too much coin on the 802g
and a solid state amplifier with a bit more power/control on the woofer


the most revealing experiments for me personally, were toying around with a Pioneer sf850... very easy to vary frequency/slope of the xo for comparison purposes....

I ended up with a preference for 12db slopes, generally....
at my chosen frequencies...


I will hopefully be putting an A5-ish rig back together next October.

I do have to admit, if I listened to just my jazz, cajun, and creole records... I could have enjoyed just the tube amp and a passive xo...

but it just didn't cut it with KISS, 2 live crew, or Ministry... IMO

Hi Old Guy,

Thanks for posting . Some comments :

You state : "20 is pretty big ie 500 Hz at 16 ohms."

I agree, and brought it up in my original post.

I was amazed that Larry Moore came to a 20 uF ( 500 Hz ) value by ear. It makes me want to do the determination myself. I wonder what he was hearing?? I would start with approximately what GM posted in 2003, ( on 511B horns with 515B woofers ), 2 mHY and 12 uF, which for 16 Ohms is 1250 Hz. I would tend to vary values around that start point.

"There are a few who advocate 6 db/octave, bear in mind it lowers power handling."


The few people who advocate 6 dB per octave are THE ONES I hope to hear from.


You, and many other people, would like to tell me otherwise ( than to use 6 dB ) in a good natured and well-meaning way. "Power handling" you mention is of NO concern when I use 1.3 Watt to 3 Watt audio amps.

OG, my 1.3 Watt SE amplifier is really about a 500 Watt power supply, with the audio amp gated to 1.3 watts. The amp's custom power transformer weighs 18 pounds, and the DCR of the power transformer and two supply chokes has less than 15 Ohms of series resistances. See my moniker, ... LowOhms.

"But best is still active crossovers and separate amps. Just my 2 cents."

Not me. no thanks !! I have NO interest in biamping or using things like active equalizers. I have been there, done that, reject it fully now. I owned two-way horn systems previously, RCA Ubangies ( two 15s) and RCA MI-1428B field coil tweeters on RCA 90 by 40 horns, biamped. Drove me crazy. I can hear the timing differences and signatures of two different amps, on the system. Each different circuit has a different time constant through the amp. No, not for me.

IF ( and "if" is a big word ) I biamped , I would ONLY use exactly the same amps and exactly the same speaker wire and wire lengths, so that the music came to me as one, a similar time constant through the electronics.

However, as soon as you biamp, you need to add an extra active amplification stage for the biamp crossover, and the system loses transparency and information ( if its a good one), just like it does when you plug an active equalizer into a great audio systrem. Not for me, thank you !! Extra interconnect wires, extra stages, all add up to LESS IF you have GREAT basic electronics and and a GREAT front end. JMHO. YMMV.

Heck, ideal may possibly be NO inductor on the woofer, as Larry Moore suggested and GM mentioned. Maybe I need to try that, on the 515B and on a wider band width 416-8B.

I try to respect all people, and I hope we will tolerate diversity of opinion. " 6 dB ers ", I think you are out there. Lets hear your experiences, comments, please. Thanks.

Jeff

I will tolerate your opinion as unsubstantiated impressions, no more or no less. If it can be substantiated as fact then we will all benefit from your experience. Interesting thoughts you put forward - just the sort of input that promotes discussion.

If you could hear timing difference you didn't do it RIGHT.

Rejecting something after doing it wrong is kinda silly.

Honestly, if you just want crossover info a general audio forum might be better. this forum is Altec specific.

And if you like to argue, try Romy the cat's forum...:D

Well, would have to side with OG somewhat.....very subjective maybe OT in the strictest sense. However I did this same route some years back and here's my... as Mah put it..."unsubstantiated impressions". If memory serves I used 511s/808s/416s. 10-15ohm resistor to pad down the HF drivers along with a 8-10uf cap and a 1uf bypass cap. The 416 was hooked up straight with no inductor. The mid and HF sounded fairly opened and detailed. However the bass for many would probably be considered thin, anemic. When I supplimented the bass with 18" B52's subs, everything seemed to (suprisingly) come together. Again...totally unsubstantiated and subjective to personal opinion , room acoustics , program material to name a few! I do think it is instructive to listen to individual drivers at times with minimal crossover components connected though. Especially for (DIY) matching/diagnostic purposes. BTW..wecome to the forum Jeff!:)

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Originally Posted by LowOhms

Hello,

I recently joined this Forum and have been getting prompts, every time I log in, to make my first post and introduce myself. O.K. !! My name is Jeff, I live in a small college town with rolling farmland all around, fifty miles outside of Kansas City, Missouri. I am a life-long audio and music enthusiast.


Treat me gently, this is my first post !! Isn’t audio fun, and music sublime ?? Thanks in advance.

Jeff

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Hello Jeff ! Welcome to the "Altec Users Board" ! It is because you are a new member with no posts...Until you get a few posts under your belt you will receive those prompts...If you join the forum and have no posts for 180 days your account will go into an inactive account mode and you won't be able to post.Until a Mod or Admin can help you back into the active members list (Unlock Your Account)..


"I pick-up 825 plywood enclosures, later this month. Hooray . ‘Have on-hand ALTEC 515B woofers, 802 tweeters , 511B horns, and parts to build a home brew crossover".


Well you do have some nice components to start with,hope your system works out.It should sound nice...

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Originally Posted by Old Guy

If you could hear timing difference you didn't do it RIGHT.

Rejecting something after doing it wrong is kinda silly.

Honestly, if you just want crossover info a general audio forum might be better. this forum is Altec specific.

And if you like to argue, try Romy the cat's forum...:D

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Hi OG,

Thanks, that is pretty funny, you have assumed I did it "wrong" and I am silly. Then you suggest I go to another Forum !!

How can I get into so much trouble in just two posts on this Forum??

Goodness, I would have thought just the opposite : " If I can readily sense the sonic signatures of two different amps, with different time constants through each, I did it very RIGHT ".

I happen to think that is pretty easy to sense OG.

Also, I don't have to prove this to anyone, other than me,.... myself being satisfied. YMMV as I originally posted, fine !! I do understand and respect that. No problem for me. Just don't tell me I am automatically wrong, because we disagree.

Finally, since my original post is specifically about Altec A7s, with Altec components, this should be the best Forum to ask others to share their experiences with 6 dB. crossovers.

Your posts, and you, are appreciated by me. Lets just say we have different listening experiences and disagree, and leave it civilly like that. Thanks for contributing !! .

Jeff

Jeff,
I think that OG was suggesting that another forum's membership may better be able to get really into the specifics of crossover design, whether it be generalized for the components or tailored to your listening environment's acoustics....

Lansing heritage has some xo experts posting frequently, as does DIY.....

I think it has to do with the expertise of the forum members on the topic at hand, rather than you getting into trouble here with the regulars

I think what OG may have been hitting at is that with a good active XO setup, you should be able to make the necessary adjustments for time delays, room acoustics, etc. As far as hearing differences with bi-amping, that would explain why you want to go with the simplest passive XO possible, since passive filters can actually introduce more issues.

I wouldn't say that I'm an advocate for 1st order XO, but I've been doing a lot of simulating, prototypes, and measurements with different filters recently. My "test bed" is a 416A in an 816 cabinet, along with 802-8G HF mounted to a 511B horn. My findings thus far is that it is hard to beat the 12dB Altec network, which includes dual HF/MF shelving controls and impedance eq on the woofer. Originally I was trying to simplify and dial in the XO to the specific drivers mentioned. I tried to lower the XO point from 1200 down a bit lower and see if the HF horns would sound richer and also see if I could improve the LF response a little bit by not having the woofer reach quite so high. I've tried 1st order HP and LP filters, 2nd order, and even 3rd order. I have also played with simple HF attenuation, and customizing the Altec dual shelving circuits. I'm zeroing in on some pretty good results, but it certainly is not leaning towards 1st order at this point.

Jeff, I simply don't care what you can sense. A GOOD active setup allows adjustments for many things. There are DOZENS of active crossovers. You tried one setup, and are now spreading the word that ALL active setups are bad. You are not qualified to say that.

Part of this is the language barrier. the words you choose come across very strong in English. I have been doing audio probably twice as long as you have been alive. I no longer have time for you or your attitude.Sorry.

Bottom line, a whole lot of equipment you have never seen. Don't judge it all before you see it.

Also benefit from a 6db xo on my A7s. The original Altec xo's were missing when I bought the used A7s; the 12db after-market replacements were dreadful. At any rate, following countless hours of trail and error settled on the 6db xo, at approximately 600hz as the most musical, transparent, and dynamic XO I could cobble together without any sort of test gear, other than my ears. Power handling is not an issue as I rarely listen above loud conversation level.
No doubt, there are issues with the xo that need to be rectify, but without proper test gear and a lack of technical skills, it?s just not going to happen.
I?ll post a drawing of the xo later, welcome all comments, useful or otherwise.
Cheers

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Originally Posted by SD-50

Also benefit from a 6db xo on my A7s. The original Altec xo's were missing when I bought the used A7s; the 12db after-market replacements were dreadful. At any rate, following countless hours of trail and error settled on the 6db xo, at approximately 600hz as the most musical, transparent, and dynamic XO I could cobble together without any sort of test gear, other than my ears. Power handling is not an issue as I rarely listen above loud conversation level.
No doubt, there are issues with the xo that need to be rectify, but without proper test gear and a lack of technical skills, it?s just not going to happen.
I?ll post a drawing of the xo later, welcome all comments, useful or otherwise.
Cheers

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My experience and conclusion as well. I was going to say in my earlier post that the 6db xo worked well at medium to moderately loud volume only. Couldn't keep up with my 19's at high volume! Would like to see your xo drawing and values.

I never cared for biamping my M19's either. And I used identical amps for highs and lows. PP 6B4G modified Heath W5's. No sand amps in my system. The issue was probably my x-overs, but just never messed with the whole thing because the stock x-over just sounded better.
I have messed with 6db slope stuff. On A7's as well. But the woofer section has a peak at 250-300hz, and that just became accentuated. To my ears anyway.
So Jeff, do it and have fun and tell us what you hear.
Ron

OG, LowOhms asked "Can I gain from your expert arcane experiences".

arcane definition: arcane - Wiktionary

Is this a speciality of yours? :o

:rolleyes2:

Can't we all just ..... Get along? And have a good time.

Jeff, there is another Jeff from your neck of the woods that posts on another forum. He has some experience with both 2A3's and Altec speakers and may be able to give you a demo or at least some local perspective on your quest.

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Originally Posted by Old Guy

Jeff, I simply don't care what you can sense. A GOOD active setup allows adjustments for many things. There are DOZENS of active crossovers. You tried one setup, and are now spreading the word that ALL active setups are bad. You are not qualified to say that.

Part of this is the language barrier. the words you choose come across very strong in English. I have been doing audio probably twice as long as you have been alive. I no longer have time for you or your attitude.Sorry.

Bottom line, a whole lot of equipment you have never seen. Don't judge it all before you see it.

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Hi OG,

You assumed things you shouldn't.

You state " I have been doing audio probably twice as long as you have been alive."

Really, I am 68 years of age. OG, have you been doing audio for 136 years ??

I was about eight years old ( guessing ) when my Dad sneaked the ALTEC 604B duplex into our home, while Mom was sleeping.

Do you have ANY idea what my background is in audio? No, you don't, not at all.

Did me mentioning using pairs of RCA Ubangies and MI-1428B field coil large format drivers in my living room register ....... mentally with you ?

Why not just leave this alone between the two of us. Peace. Heck, it is possible I may be older than you and / or more experienced with high end audio than you. It really doesn't matter at all. What matters is this : we both derive fun from our respective audio hobbies !! Also, we should be respectful to each other.

Now, in January 2013, I am simply interested in exploring 6 dB passive crossovers topics with those Altec A7 users that are either doing it, or have done it and those who tried it and discarded it !!

You are right about communicating on line. It leaves a LOT to be desired compared, say, to even a simple telephone call. Better yet, I wish I could meet you, break bread together ( except I am a vegetarian and I don't eat bread ) ...we would probably have a lot of fun together. Hey, attend RMAF 2014 in Denver, we will meet, I'll be there, running GPA 15s in a nice MLTL, for my best friends. Single amped,....one 2A3.

Cheers,

Jeff

is RMAF a great show? I should take off and attend some year...

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Originally Posted by RonSSS

I never cared for biamping my M19's either. And I used identical amps for highs and lows. PP 6B4G modified Heath W5's. No sand amps in my system. The issue was probably my x-overs, but just never messed with the whole thing because the stock x-over just sounded better.
I have messed with 6db slope stuff. On A7's as well. But the woofer section has a peak at 250-300hz, and that just became accentuated. To my ears anyway.
So Jeff, do it and have fun and tell us what you hear.
Ron

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Did you see how Dominique ( as posted on this Forum ) measured a huge peak, maybe 10 dB at around 240 HZ? As soon as he put three-sided wings on, it measured 4 dB less. He also ( IIRC) added a felt damping material - hanging inside the bass enclosure, and got it even better.

He was guessing it has to do with the frequency of the horn mouth, as determined by the distances, and wave lengths. When you add wings, it ameliorates this 240 HZ peak some, but not completely. ( It makes the bass horn mouth " look " larger. ) So Ron, I am guessing the problem you discuss is probably a function of the enclosure being only partially horn loaded, and not so much a crossover thing. My guess, I am not a speaker guru !!

Thanks for posting. Larry D. Moore nicely covers this 6 dB stuff, sorta interesting to read his Issue Six.

Jeff

LowOhms, your statement, "Please don't let the many Forum members, with huge listening rooms, solid state(sic) amps and active equalizers scare you off!! Allow your minority voice to be heard". would not be a good way to win friends on any forum. You have, in your first post, made a generalised slur on many of this forums members. I think the response has been quite gentle considering the double exclamation mark you used for additional emphasis.

Now, back to the topic.....................

Quote:

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Originally Posted by SD-50

Also benefit from a 6db xo on my A7s. The original Altec xo's were missing when I bought the used A7s; the 12db after-market replacements were dreadful. At any rate, following countless hours of trail and error settled on the 6db xo, at approximately 600hz as the most musical, transparent, and dynamic XO I could cobble together without any sort of test gear, other than my ears. Power handling is not an issue as I rarely listen above loud conversation level.
No doubt, there are issues with the xo that need to be rectify, but without proper test gear and a lack of technical skills, it?s just not going to happen.
I?ll post a drawing of the xo later, welcome all comments, useful or otherwise.
Cheers

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Hi SD 50 !!!

Yours was a post I was looking for. There must be others too. You and Larry Moore settled on a similar approach...by ear. Yes, others would like to see your schematic.

I am so HAPPY you responded.

There are two things I'd like to send you, if you are open to looking them over. One would be Larry D. Moore Esquire's A7 write up, done a number of years ago. Another is a SERIES crossover " primer ", two way and three way at 6 dB, instead of the usual Parallel passive crossovers. The same parts are employed, just minor / different wiring. Some ( Dominique, Paul Eizak, Bud Fried ) say SERIES sounds superior. Just need your email address, to send the info. as attachments. ( Any one else is welcome to it. )

What ALTEC components do you run? What power amps do you use ? Curious minds want to know. THANKS for posting sir.

Jeff

(Insert Popcorn eating emoticon here) :D

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Originally Posted by LowOhms

Did you see how Dominique ( as posted on this Forum ) measured a huge peak, maybe 10 dB at around 240 HZ? As soon as he put three-sided wings on, it measured 4 dB less. He also ( IIRC) added a felt damping material - hanging inside the bass enclosure, and got it even better.

He was guessing it has to do with the frequency of the horn mouth, as determined by the distances, and wave lengths. When you add wings, it ameliorates this 240 HZ peak some, but not completely. ( It makes the bass horn mouth " look " larger. ) So Ron, I am guessing the problem you discuss is probably a function of the enclosure being only partially horn loaded, and not so much a crossover thing. My guess, I am not a speaker guru !!

Thanks for posting. Larry D. Moore nicely covers this 6 dB stuff, sorta interesting to read his Issue Six.

Jeff

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Strictly enclosure thing. I think it's pretty well documented. I measured it. Basically why I'm not an A7 fan....I use an EQ to tune it out.
I actually have a pair of a7's now, and that's what I'm doing. But these are used for TV mostly, not really hi fi.
I'm honestly thinking A7's are going to frustrate you. But play on! I bet you would love some duplexes better.
Ron

Quote:

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Originally Posted by mah

LowOhms, your statement, "Please don't let the many Forum members, with huge listening rooms, solid state(sic) amps and active equalizers scare you off!! Allow your minority voice to be heard". would not be a good way to win friends on any forum. You have, in your first post, made a generalised slur on many of this forums members. I think the response has been quite gentle considering the double exclamation mark you used for additional emphasis.

Now, back to the topic.....................

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Perfectly good point and I agree. Its hard doing things by typing. It was said in jest, and there is no way I can show that inflection, except, if I put a smiley behind the end of the sentence, which seemed corny at the time to me. Wish I had. I apologize to any and all I offended. You are very right about that.

Yes, back to the topic, THANKS for pointing that out to me.

Jeff

Quote:

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Originally Posted by RonSSS

Strictly enclosure thing. I think it's pretty well documented. I measured it. Basically why I'm not an A7 fan....I use an EQ to tune it out.
I actually have a pair of a7's now, and that's what I'm doing. But these are used for TV mostly, not really hi fi.
I'm honestly thinking A7's are going to frustrate you. But play on! I bet you would love some duplexes better.
Ron

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I've heard GPA duplexes in very well-made MLTLs on SOTA gear, and there is a lot to be said for a point source. Recall, I grew up with 604Bs as a child.

Ron, I hear a SMALL discontinuity in the midrange, I am guessing where the two drivers cross over, that makes me think I would not be pleased, long term with them. I am very open to the idea of a duplex, but I am scared to death to commit from what I have heard at RMAFs, the last six years. Maybe I will learn from Forum members, new facts on 604s, or combinations thereof, unknown to me presently. Its an "open" thing for me as of now.


YES, I was guessing, up-front that A7s are a risk. If money was not a factor, I'd run a good Danley Synergy horn. Oh well, the money is a factor.

Jeff

FYI: 3-way, all 6dB/octave, with Altec 515G

6moons industry features: La Grande Castine

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Originally Posted by badtoby

Can't we all just ..... Get along? And have a good time.

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Sorry...but I work methodically. Irritated by amps with different timings? Then use amps with the same timings, Easy. But to scrap an entire concept after doing it badly by throwing stuff together, then crowing about how bad the concept is, just makes me wanna say, Hey, got things to do better than putting up with you.

Bad plans equal bad results, but no plans equal worse results than bad plans.

I don't have bad feelings towards Jeff, just got better things to do.

I repeat myself here: why audition hi-end systems in hotel/motel rooms, or any system for that matter?

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Originally Posted by mah

I repeat myself here: why audition hi-end systems in hotel/motel rooms, or any system for that matter?

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Does sound a bit odd. Motel rooms often are "dead" sounding on purpose....

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Originally Posted by Old Guy

Sorry...but I work methodically. Irritated by amps with different timings? Then use amps with the same timings, Easy. But to scrap an entire concept after doing it badly by throwing stuff together, then crowing about how bad the concept is, just makes me wanna say, Hey, got things to do better than putting up with you.

Bad plans equal bad results, but no plans equal worse results than bad plans.

I don't have bad feelings towards Jeff, just got better things to do.

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OG,

You write :

"after doing it badly by throwing stuff together, then crowing about how bad the concept is,"

WHAT ?? You are assuming things again ......... ass/u/me.

You have no idea what and whose biamped systems I have listened to, and what I have personally done, running biamped systems, for me to form my conclusion.

If you believe biamped A7s is the way to go, fine, I respect and fully understand your thought process OG, and your right to choose what you like!! Do it in your home, enjoy yourself.

Likewise, might you possibly be able accept the fact that biamping is simply not my cup of tea. I am a "single, really good amp, on the whole system" type of listener.

So what is "my" thought process, OG ?? " Minimal messing with the audio signal,.... minimal stages - just enough to get the job properly done". I think long and hard before I add an active stage and extra interconnect wires to my system. KISS ( less is more ) rules.... in my book.

I THINK I have spelled out our differences well enough.

Can we just understand, accept and respect each other, relax some, and get off this non-productive tangent henceforth ?? Thanks!

Now, where were we...ohh yes, 6 dB octave passive crossovers - on A7s.

Jeff

Jeff, what are your impressions/preferences with respect to PIO, tantalum, electrolytics, metal film, etc as condenser component choices in deploying a 6db xo?

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Originally Posted by Old Guy

Does sound a bit odd. Motel rooms often are "dead" sounding on purpose....

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So is my personal listening room.

Quote:

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Originally Posted by just me now

Jeff, what are your impressions/preferences with respect to PIO, tantalum, electrolytics, metal film, etc as condenser component choices in deploying a 6db xo?

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I am not a speaker guy. I don't have my A7 enclosures yet !! I would need to listen to crossover caps and decide.

I would listen to bipolar electrolytics battery biased also !!! Some very very high end boutique horn manufacturers tell me that battery biased bipolars are quite good sounding !! All possibilities I can afford - is on the table. How about Russian MBGO 2s, or Dynami Caps? How about multiple bypassing of Dynamis, specifically ( they can "add" OK. ) How about films battery biased ??

I am NOT at all a very big fan of using a single resistor in series. I will usually opt for TWO equal value resistors, closely matched, at double the needed value, in parallel, so I have TWO wire paths, and best "transfer efficiency". I LOVE doing and hearing THAT !! Its so audible. In DIY tube amps, it is a "must" on Rks, for best audio performance. I LIKE Mills MRA-12s in certain places in amps, high powered Rks, etc.

I like to use Kimber Kable TCSS in parallel runs, usually three paralleled to a woofer, two to upper frequency drivers. If I could afford it, I'd use all Siltech, but that is out of my league, financially.

I have not tried it all, but you asked for my "favs." What are yours ??

Jeff

Ping, James Randi.

Bulldust Alert, Bulldust Alert.

I rest my case.

Some basics:

Circuit Theory/Maximum Power Transfer - Wikibooks, open books for an open world

Cathode bias - Wikipedia, the free encyclopedia

Some reference material:

A Bibliography of must have tube electronics books

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Originally Posted by LowOhms

I have not tried it all, but you asked for my "favs." What are yours

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I've also not had the opportunity to evaluate many...
but have also read the talk surrounding charge coupled networks...

I run my set up multi amplified, 6 channels per stereo side...
it its not a normal "hi-fi" type of system in configuration...

more of a vintage early NYC clubsound style of deployment...

the components used in the active crossovers I use are quite pedestrian,
my understanding is that "back in the day" almost all of them were acquirable on canal st in NY, likely for Pennies in the bargin bins

the sound reproduction from these old RLA and Sound Environments "DJ crossovers" is sublime imho, despite the "low end" items in the signal path

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Originally Posted by Old Guy

I rest my case.

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Is the fun over already? :D (We will now return to your original scheduled program) :D