The 1960's Magnavox console stereo my parents owned had Heppner horns pointing left and right and the woofers straight forward.
I remember liking the sound laying on the floor between the woofers, but "almost nowhere" would be a good descriptor of the sound almost everywhere else 😉 .
What is your recommendation with th-4001 horn? Tad drivers r out of game. Woofers are jbl 2226.
Leave the 2022 horns out of it.
If the listening room is large enough I also use JBL2226, but they do not go very deep. Below 90Hz ish you need a sub.
With the JBL2226's I use JBL 2123's for mids.
It is not about preferring near, mid or far but what fits in the space, I use a large work bench, only small speakers will fit on the bench top. Currently mini enclosures with 6 1/2 inch Purify mid-bass drivers. And no they are not headphones, there is a sound stage that spreads out on the bench, not just between the ears. Yes they are mostly direct sound and not so so much reflected sound from the room.
If the listening room is large enough I also use JBL2226, but they do not go very deep. Below 90Hz ish you need a sub.
With the JBL2226's I use JBL 2123's for mids.
It is not about preferring near, mid or far but what fits in the space, I use a large work bench, only small speakers will fit on the bench top. Currently mini enclosures with 6 1/2 inch Purify mid-bass drivers. And no they are not headphones, there is a sound stage that spreads out on the bench, not just between the ears. Yes they are mostly direct sound and not so so much reflected sound from the room.
btw, are some of you benchmarked CD+horn VS more traditional hifi tweeter but wave guided ? SPL is close if of any convenience as it has to be tamed for home use, anyway.
Is the said dynamic factor (PRAT?) still happen here in favor of the compression driver + horn? I assume also the difference in the soundstage : more focussed with the compression driver + horn and most of the time, more airy and less focused with traditional wave guided dome tweeters, rigth ?
Is the said dynamic factor (PRAT?) still happen here in favor of the compression driver + horn? I assume also the difference in the soundstage : more focussed with the compression driver + horn and most of the time, more airy and less focused with traditional wave guided dome tweeters, rigth ?
This is not my experience. I used the "cutoff" as part of the HP filter. I don't find that the phase "can jump wildly." It's simply the phase of the HP filter of the completed design.
I find the opposite to be true. The driver makes very little difference to the sound quality. It's the waveguide that dominates the sound quality not the driver. About the only thing important about the driver is its power handling/excursion limits. Compression drivers are pretty much a commodity being almost all the same.
what about the guys saying any 1" sound "compressed", not pretty, below 1200 hz whatever the horn ?
I mean what the technical evidences against that opinion ?
At leasy, has all OS/Horn need to be anti-holms foamed ?
thanks (sorry for the naives questions, all of that way above my head, early reflexions took into acount)
I mean what the technical evidences against that opinion ?
At leasy, has all OS/Horn need to be anti-holms foamed ?
thanks (sorry for the naives questions, all of that way above my head, early reflexions took into acount)
I give zero credence to subjective opinions. Too much experience with subjective testing to ever take anyones singular opinion seriously. For example, when I was at Ford we did what is called a "gauge capability study" of out "expert listening panel." This study was used to determine how reliable their subjective ratings were from test to test. Of the ten that were tested only two could reliably rate systems from one test to another. And this was all done blind!! Given non-blind testing, the bias will overcome everything.
Technically a waveguide system is just an acoustic HP filter of about 18 dB/oct (cutoff) followed by a LP slope of 6 dB/oct (flat power response from a constant directivity source.) In my system I use an additional 6 dB/oct HP filter at about 10 kHz. This yields a flat passband (in both axial SPL and power response) from "cutoff" up to the drivers HF limitations. The HP is now 4th order with exactly the same phase as any other 4th order system - passive, electric, whatever. The only limit to this approach is over excursion at the low end. But given the power output of a compression driver in a small HT this is never an issue. It IS certainly an issue with sound reinforcement, but that's another topic altogether.
I can't decipher your last question, sorry.
Technically a waveguide system is just an acoustic HP filter of about 18 dB/oct (cutoff) followed by a LP slope of 6 dB/oct (flat power response from a constant directivity source.) In my system I use an additional 6 dB/oct HP filter at about 10 kHz. This yields a flat passband (in both axial SPL and power response) from "cutoff" up to the drivers HF limitations. The HP is now 4th order with exactly the same phase as any other 4th order system - passive, electric, whatever. The only limit to this approach is over excursion at the low end. But given the power output of a compression driver in a small HT this is never an issue. It IS certainly an issue with sound reinforcement, but that's another topic altogether.
I can't decipher your last question, sorry.
thanks.
the time I understand holm foam things gives me margin to focus on the foam/horn question. I'm a low efficient guy 🙂
the time I understand holm foam things gives me margin to focus on the foam/horn question. I'm a low efficient guy 🙂
@gedlee - My experiences differ from yours. Running a CD + WG down to cutoff (especially when it has a lot of FR ripple) and using this area of response in the xover slope rarely ever yields the clarity I'm after when designing an HE 2 way speaker. Even if the source of FR issues are baffle step related or otherwise, it wouldn't work out very well unless applying a bunch of dsp correction. Even then its still uncertain if you can get away with it and call it a successful implementation of components.
Also, it was you I previously remember saying the CD makes little to no difference in performance in comparison to the WG itself. This would imply one could pair any old cheap junk CD with a good WG and results would be the same as when using a higher end ie. Faital or BMS driver. Even keeping things like driver exit angle and throat depth out of the equation, it still wouldnt be explained with a simple black and white generalization. We all know that various CD throat lengths and designs have effects on overall performance coupled to various WGs, so that in itself shows this theory isn't completely true.
I have my own experiences to back my findings up for my own self. My results may not be fully documented, but it doesn't immediately prove you're right or I'm wrong either, regardless of how much you label my findings as subjective and non scientific. I'm not here to argue with or have someone beat me up with their academic achievements. I'm here to share my experiences with others so they may benefit (at their own discretion).
Also, it was you I previously remember saying the CD makes little to no difference in performance in comparison to the WG itself. This would imply one could pair any old cheap junk CD with a good WG and results would be the same as when using a higher end ie. Faital or BMS driver. Even keeping things like driver exit angle and throat depth out of the equation, it still wouldnt be explained with a simple black and white generalization. We all know that various CD throat lengths and designs have effects on overall performance coupled to various WGs, so that in itself shows this theory isn't completely true.
I have my own experiences to back my findings up for my own self. My results may not be fully documented, but it doesn't immediately prove you're right or I'm wrong either, regardless of how much you label my findings as subjective and non scientific. I'm not here to argue with or have someone beat me up with their academic achievements. I'm here to share my experiences with others so they may benefit (at their own discretion).
I’m currently using the JBL2226 and I thought of changing to a better balance, what will be your suggestion? Does the JBL 2123 sounds well and better of than the 2226?
There is a huge continuum of devices ranging from horns with exponential throats and very defined cut offs (where because of the increased slope the phase does change more steeply) to waveguides more like Earl's where the waveguide gives out gracefully as frequency goes down without any real cutoff to speak of. I think you can both be right if speaking about different devices.
May I ask what was the slope and cut-off point you chose with the Abbey loudspeaker that used a 12" and a 1" ... I am trying to make a humble 2 ways inspired from that and the good work of mabat with a Faital 12" I sourced not to expensive. I should use the standard ST260 wave guide and a 1" from BMS that has already a low possible cut-off for PA application (800 hz) and I use it for normal home hifi. It is for try horn and constant directivity...
I remember it was not a problem reading at you in threads here to use a compression driver (but needs EQ) below its F for home applications, IIRC.
People here advice a 1100/1200 hz cut-off with the ST260. While the ST260 has an off axis that would be ok around 800 hz with that Faital 12" , many said the 1" sounded a little dirt below that 1100/1200 hz. Limitation seems not ot be the ST260, nore the Faital 12PR320 12" midbass but the BMS 1" !
Thanks if any thoughs, (but ok I know I have to try to know for real, it is just I do not consume as much as speakers as it could need to know). I am very attracted btw to put a 5" to 8" between the ST260 and the 12", but I already know that was not your philosophy, frankly I have zero experiencece and listenings with such high spl 2 ways with good horn. Basic debat between precisiion given by a dedicated midrangge ot the more subjective dynamic prat/pun ch than compression drivers seem to add to the listening experience (of course in plus with the managed directivity of the horn/WG)
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Let me give you the data that we have.
Many years ago I arraigned a blind test using some 30 members of our local audio club. There were four speakers that each subject would rate. Two were identical system designs (2-way with waveguide - Summa) but utilized different drivers sets - one very high end set of TADs and the other inexpensive B&C. The third was a three way direct radiating and the last a commercial two-way with horn.
The results showed that there was no statistical difference between the two driver sets on the same system design, but there were definitely differences between those two speakers and the other two.
Could a very poor set of drivers in one of the identical systems have changed these results? Possibly - the drivers could maybe make a difference, but in our case they didn't, and these sets of drivers had an almost 10x difference in cost. So I am not saying that an extremely poor driver would not be audible, only that an extremely different set of drivers weren't.
I described the HP above. The crossover for the Abbey was at about 1 kHz, while the Summa was at about 800 Hz, the difference resulting from the smaller waveguide and woofer in the Abbey which did not allow for directivity matching at a lower crossover point. My crossover designs were always chosen based primarily on directivity matching of the two driver sets. In both of these systems the LP was 3rd order. (But these details did vary considerably over time.)
If by "F" you mean the theoretical "cutoff", that is true.
Please describe the whole signal path incl. source and used music tracks used for the test. I'm not saying that it matters, I'm just curious 😉
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Signal path was identical in all four systems, (the speakers were switch with the speaker leads from the amp,) but I don't remember the details. Sound levels were adjusted to be the same because all the speakers had different sensitivity. I also don't remember the songs, but there were a variety. Sorry, it was a long time ago and I don't think that any of this would have made any difference, which is why I didn't retain the info.
I've done a lot of subjective testing and my wife is trained (PhD) in psychological testing methods and analyzed the results. This was a well thought out experiment.
I've done a lot of subjective testing and my wife is trained (PhD) in psychological testing methods and analyzed the results. This was a well thought out experiment.