My "New" 4345 Clones

[JBLRaiser]

I've been in the AV business for 25 years, and one thing I'll tell you - it's much easier to fix it over the phone than it is over a forum.

Much.

Real-time feedback, plus the ability to ascertain the knowledge & comprehension levels of the end user are quite helpful. However, phone-fixes are often only possible for me if the person at the other end becomes my eyes/ears/hands, and otherwise says nothing besides answering my questions directly.

je

I couldn't have put it better myself.

[BMWCCA]

I've been in the AV business for 25 years, and one thing I'll tell you - it's much easier to fix it over the phone than it is over a forum.

Much.

If I'd taken each piece of advice offered in this thread since post #89 in the order it was offered, I'd still be swapping polarity at the LF today. The number of conflicting opinions, opinions posted as fact, incomplete reading of the facts involved, contradictory solutions from even the same poster, references to manuals for products not even being used, demeaning references to literacy or lack thereof, all the Sturm und Drang over the genesis of the CC crossovers and the providence of their design, plus the discrediting of experts by other experts here leave a novice like me with no choice but to ignore everything, put the computer to sleep, and play music.

Maybe you long-suffering forum stalwarts know whose advice to take and whose to ignore, but the rest of us don't. A simple question about tracing the polarity through the network devolved into tale-chasing. That's partially due to my inexperience, my natural tendency to trust the expertise of others in an area outside my field of knowledge, and my not being able to separate the wheat from the chaff. What seemed a simple question to me apparently had either no answer, several answers, or none that made any difference. I'm just happy to have the music.

To all of you, thanks again for your help.

[Mr. Widget]

I've been in the AV business for 25 years, and one thing I'll tell you - it's much easier to fix it over the phone than it is over a forum.

Much.

Real-time feedback, plus the ability to ascertain the knowledge & comprehension levels of the end user are quite helpful. However, phone-fixes are often only possible for me if the person at the other end becomes my eyes/ears/hands, and otherwise says nothing besides answering my questions directly.

je

Very well put.

Fortunately most of the time the poster seems to get it with less drama, but every so often we enter into a tail spin of good advice sprinkled with a red herring or two and it all goes to shit.

I don't know why a simple post like Rob's post 89 where he brought up the fact that a 24dB network like the Ashly does not invert phase and the stock 12dB network does caused so much confusion, a confusion that apparently still lingers in the mind of BMWCCA, but I guess without that phone call we are stuck with these outcomes occasionally.

At least at this point it would seem the speakers are doing what they are supposed to do... make music!


Widget

[BMWCCA]

I don't know why a simple post like Rob's post 89 where he brought up the fact that a 24dB network like the Ashly does not invert phase and the stock 12dB network does caused so much confusion, a confusion that apparently still lingers in the mind of BMWCCA, but I guess without that phone call we are stuck with these outcomes occasionally.

Which post #89 are you reading?

What is the phase on the woofer?? When I run a 24db network on the 4344 I have to reverse the phase. The original is a 12db network with a 24dB L/R they should be in phase.

If you think that instruction is clear, you must be a manual editor—and the last sentence cries out for punctuation to make any sense at all! But the confusion starts with, "I have to reverse the phase." From what? According to the original 3145 schematic, the HF and LF are already reversed in polarity relative to each other, supposedly to keep them in-phase. So, what: reverse the reverse? Easy for you to say. In normal English it might be argued that you don't "reverse" phase; you're either in-phase, or out-of-phase". You reverse "polarity" to effect either result in phase status. I respectully suggest you're inferring information that wasn't given—or given in a syntax that defies normal understanding.

"In-phase" just might occur with polarity reversed. "Reverse the phase" in English is not the same as "reverse the polarity". One phrase implies the result of two speakers not in-phase, the other simply implies changing wires to reverse polarity without regard to ultimate phase.

Here's what I think the well-meaning here were actually trying to tell me—in my own words:

The original 3245 network supplied with the 4345 uses a 12dB slope on the LF section which reverses polarity within its circuitry, so it is necessary (as shown in the schematic) to reverse the polarity (red wire to black terminal and black wire to red terminal) on the 2245H to keep the drivers in-phase during operation.

When bi-amping using a 24dB-slope active crossover, such as an Ashly XR1001, and by-passing any LF internal network, polarity is not reversed within the circuitry so retaining conventional wiring polarity (red to red, black to black) should result in both drivers being in-phase during operation.

But then we get an agreement to the contrary with Bo and Heather who say it ultimately may be a matter of personal preference and what the listener hears:

I'm running my 15s reversed - tho I had mistakenly run then in phase before.
Out of phase you'll get a sharper cutoff between the woofer and the 10 inch

Yes, Heather - be careful of this. You may be right because of the 4th Order slope of the XR1001, but I need to review the schematics (and I'm bushed from coming off a small tour...). Have you found them more to your liking, this way?

Last night mid the 1st set, we inverted the subs on a sizeable system in Tahoe - the systems guys (nameless here) insisted that in over 1,000 shows no-one had ever requested this. It immediately smoothed the response curve and gave ME control over the VLF - I was able to flatten the GEQ, removing some nasty notches they had been accustomed to "needing". Clearly, there was some unintended additive/doubling in the acoustic domain with being electrically in-phase (relates to the phenomenon of "physical offset"). The LF loading at stage was abruptly far, far less - the bassist was able to hear better and so turned down his rig. And, I could ease the whole system gain down because things became far more intelligible.

I love you all dearly, but if you don't think the advice given here by some isn't contradictory to that of others (or written in such fashion as to defy comprehension), then we don't speak the same language. An observation that is becoming clearer with each sanctimonious post.



"The problem with communication ... is the illusion that it has been accomplished." –George Bernard Shaw

[hjames]

I love you all dearly, but if you don't think the advice given here by some isn't contradictory to that of others (or written in such fashion as to defy comprehension), then we don't speak the same language.

Do you have any idea how much your wife has been paying us to torment you like this ... Your daughters are in on it too!
... they want you to stop playing with these big crazy boxes,
grow up, and buy some nice bozo speakers for the house ...

[Fred Sanford]

I love you all dearly, but if you don't think the advice given here by some isn't contradictory to that of others (or written in such fashion as to defy comprehension), then we don't speak the same language. An observation that is becoming clearer with each sanctimonious post.

This goes back to my post #150:

Just as an observation, I think that much of the confusion is based on the fact that there are a large number of actual and assumed places where phase can be/might be/should be changed in the path-

1. internal to the active crossover
2. slope of the crossover
3. phase between input & output of the amplifiers
4. phase between input & output of the passive x-over
5. relation between red speaker terminal and actual cone motion

Unless all are taken into account (or stated plainly as tested with this system's components) then answers that may be technically "correct" can appear to be contradictory. Unless all are stated in the typed answer, you can't know whether they were all taken into account.

Yeah. Good luck with that.

je

...and #165:

I've been in the AV business for 25 years, and one thing I'll tell you - it's much easier to fix it over the phone than it is over a forum.

Much.

Real-time feedback, plus the ability to ascertain the knowledge & comprehension levels of the end user are quite helpful. However, phone-fixes are often only possible for me if the person at the other end becomes my eyes/ears/hands, and otherwise says nothing besides answering my questions directly.

je

As much as you might want clear, concise answers, they're not going to be clear without context, and they're not going to be concise without the context expressly stated. Some folks here weren't familiar with the particular speakers, or the crossover, or your knowledge level. Some folks have the knowledge & skills, but spotty reading comprehension/retention. Some have it all together, but followed a post that was vague, so lost clarity just by its position in line.

My advice (having dealt with you in person and on the phone) is to lower your expectations of what a forum environment can give you here - expect to learn & find resources, but maybe be careful not to expect answers unless they're from a manual. Just my opinion.

ANYBODY would get confused trying to follow, especially with the phase/polarity details you laid out. Enjoy the tunes.

je

[Mr. Widget]

Which post #89 are you reading?
If you think that instruction is clear, you must be a manual editor—and the last sentence cries out for punctuation to make any sense at all! But the confusion starts with, "I have to reverse the phase." From what?

From the factory specified orientation!

Rob asked me to re-read posts 89-95. I agree with you that there is some confusing text there, but the message is consistant. So here it is, for what I hope is the very last time:

If you use a 4th order network (and currently you are) wire the 2245 with the same polarity as the HF portion of the system.


Widget

[BMWCCA]

Rob asked me to re-read posts 89-95. I agree with you that there is some confusing text there, but the message is consistant. So here it is, for what I hope is the very last time:
If you use a 4th order network (and currently you are) wire the 2245 with the same polarity as the HF portion of the system.

Thank you.

And for your perseverance, as well.

That's where I had them in the first place!

[Ian Mackenzie]

I think the problem is perhaps information overload and then the digestion of that cognitively or lack of it arrive some valid conclusions.

If the total idiot only did exactly as he was told under direct instruction steps 1- 10 like in a manual we probably would not be wasting time over who said what.

But because this is not a simple subject and must be leant and understood before proceeding there are going to be pauses, questions and doubts before forming conclusions and they may not be valid conclusions.

The interpration and understanding of this volume of information is not an overnight event where the receiver is left to his own intuition and will only lead to confusion.

Intuition is a dangerous thing where the reciever does not really understand the information. This is the problem.

Hence we are seeing the rhetorical feedback

Its a bit like compressing a 5 year learning journey for some into a few days with the expectation that you think you will make sense out of it which of course is absurd.

The type of discussion happening now is indicative of that.

As I said earlier the real deal with these things is as much about growing to know them as it is listening to them and the more you get to know them the more useful you will find the posts.

Give it time and it will all make sense.

[BMWCCA]

If the total idiot only did exactly as he was told under direct instruction steps 1- 10 like in a manual we probably would not be wasting time over who said what.

This idiot is writing that manual right now. In fact I think I did it six-posts back. In around one-hundred words in two paragraphs.

Somehow this thread took over one-hundred posts and many still can't agree!




"A mind is a terrible thing . . . "

[BMWCCA]

Inspired by Fred Sanford's "Soundcheck" compilation used in the infamous 4333/L7 "Shootout", I dug out the "Double Vision" CD of Bob James and David Sanborn.

Horns on horns, again.

I'm not sure how it could get much better than this, but a year from now I'll let you know.

[Robh3606]

Hello Ian

Since my post about driver phase seems to have started this whole thing why don't we just end it and move on. I can't see letting this get anymore destructive than it already has become. All of the people trying to help did so in the spirit of helping a forum member get the most of his system.

It got frustrating and this showed in some posts. The bottom line is we now have a concensus that there is a correct way to phase these systems when biamping them. That really was the point of my original post.

As far as the the confusion caused by my posts wording, well it certainly was not written with malicious intent. It was also clarified a couple of posts later at post 95 when it was obviuous there was some confusion.

No it depends on the crossovers type used and the slopes 12db vs 24db. For example I can use either an M552 or my DX-1 to biamp my 4344's. The M552 is 24db L/R and the DX-1 is 12dB. When I hook up the DX-1 the woofer phase is per the original design because it uses 12db slopes like the passive network. When I use the M552 I must reverse the woofer phase for it to sum properly because it uses the 24Db slopes.

To keep it simple general rule of thump is 12db reverse polarity on one driver, 18db can end up either way and 24db in phase.

Looking at a standard cabinet you would simply reverse the phase on the woofer to use the Ashley or any other crossover using the 24db filters.

To see whats what take a 1.5 volt battery and see which direction the 2122 goes in. The series caps in the crossover will protect compresion driver and ring radiator from the DC. All you need to do is verify the woofer using the same method and connect them so they both go in the same direction. Once you do that you know the polarties are correct.

Considering that the schematic was posted by me back at post 32 I didn't think that the original post was that hard to follow looking at the schematic and reading the post. So much for good intentions.

Rob

[BMWCCA]

Since my post about driver phase seems to have started this whole thing why don't we just end it and move on. I can't see letting this get anymore destructive than it already has become. All of the people trying to help did so in the spirit of helping a forum member get the most of his system.

Thanks, and that's how I took it. I did the battery test and put the LF and MF in-phase based on the help here and from PMs. There remains the suggestion that there could be a benefit to running out-of-phase, though that is left to personal preference and listening. Nothing more really needs to be said on that topic since I know now that JBL reversed polarity by design to end up with the cones in-phase.

The phase issue is where we unfortunately began to fall apart, shortly after this post. Anyone looking for similar assistance from this thread in the future should be aware of the pitfalls I discovered upon reflection: Part of the impediment to my comprehension came from the fact that nothing in the Ashly manual tells you that the XR1001 uses a 24dB slope while much of the advice discussed phase issues related to 12dB versus 24dB slopes in the abstract. If you download the current XR-1001 manual from Ashly there is not even a mention of polarity remaining linear through the crossover, much less slope. Only if you dig down to the "old" Ashly web site and download the manual for the discontinued (gray-face) XR1001 do you see the note that "The outputs of all Ashly crossovers are in phase with the input." But Ashly obfuscates that with statements like this from the older version (which doesn't appear in the current manual):

NOTE: The Response control is not a “slope” control. A 12dB/octave crossover will always have a slope of 12dB/octave regardless of the setting of this control. Likewise, a 24dB/octave crossover will always have a slope of 24dB/octave.

and yet they still don't tell you in their specs that the Ashly uses a 24dB slope!! However, IF you have the older unit, it's right there on the front panel (but nowhere else):


If you have the new version, it's apparently a secret!:


So, upon reflection, we had a perfect storm of assumptions, different knowledge levels, and lack of information—or two versions of the same information, neither with enough of what was necessary for me to understand all the references or learn anything from them.

No hard feelings on my part, and if there remain any members offended by what I wrote—for whatever reason—you have my sincere apology. For anyone who cares at this point, the 4345's sound fantastic, and the LF and MF cones are currently running "out-of-phase".

[boputnam]

...nothing in the Ashly manual tells you that the XR1001 uses a 24dB slope...

Now that is really weird.

The do mention it on the website - first bullet point in that smallest print! - but nothing nowhere in the manual. The spec sheet has it. All-in-all, weird.

"Why didn't you say so! That, is a horse of a different color!" (Wizard of Oz)

I'll send 'em an email...

[BMWCCA]

At some point later in the year as mentioned in another thread biamping the 4345 will be looked at.

But no matter what you do this system seems to work in spite of itself and has the greatest potential for stellar performance in the right hands.

Thanks for the additional information.

I have to admit not only is it more than I ever asked for, it is also likely more than I am able to absorb. But thanks anyway.

I have no idea what your bi-amping reference refers to. The whole point of this thread is that I am bi-amping—right now. Otherwise I'd have no need for the active crossover. If you plan on going over all of this again in a year, let me know about it after you've completed the discussion. It should be quite obvious I have nothing to contribute to such a conversation! But thanks for trying.