Jessie, in the configurations of the horns and derivers that you are building your mid channels do not exposed too much to stresses. It is not that you have a situation when 1/4 octave more and less will send your channels into suffocation - your horns/drivers operate within a relatively middle and secure ground. You might move them up and down as much as you wish (still within the boundaries of the horns rates), it is all educational but you need to also measurers them to make sure that you still have overall flat response.

I do not see your today finding as something that you will accept as final for yourself. If you decide to go 5-chennal with active amplification with your horns then the character of the MF sound will change.  It will not be “different” but it will be altered and you might review your positions how the best to mix those 3 channels. I am listening now left channel (because the first violins are there) with new 6-channels Milq and the  fully “active” Macondo and I might say that “active” Macondo has own, more advanced, Sound compare to the right channel, still driven by 3-channels Milq.

I somehow feel not comfortable that what I went to line-level crossover I somehow decided to replicate the crossovering patters that I have with speaker-level crossover. Well, I went to 6dB/octave on the Fundamentals’ Channel high-pass but the rest was the same…. It might be worth to experiment and perhaps to altar the crossover points again, but I wish I would have time and desire to do all over it again.

Consequently, what I am trying to say – if you defiantly go for DSETs to each channel then hold your experiments to the times when you will be able to conduct the experiments at line level. Then you will borrow or lease an active multi-channel crossover (digital of analog) for a weekend and will easy mimic all imaginary configurations – very educational  (I did it in a past). Do not forget that in active configuration you have control over harmonics of EACH channel and it will be a big dissimilarity. I very much presume that your findings now and then might be different…

The Injection set acridness of tonal colors; it is like vinegar that added to food. The Fundamentals Channel sets the density of the food itself. It is like Fundamentals Channel distinct meet from fish but the Injection Channel set a distinction between Caspian Osetr and Atlantic Herring. The Injection Channel set the “saturation of quality or tone” vs. the Fundamentals Channel more like set the amount of second harmonics and the tone weight. That are different and excessive too much application of each of them is not desirable and it is highly unlikely that it would be possible to fit in one channel the duty of the both Channels. it might be possible if I custom built an enclosure for Fundamentals Channel, very precisely circulating the output at upperbass and lover midrange for a given room and using a driver in there with a predicable among of injection “acridness”. Unfortunately I have no such skills, so to me the use of independent Channel with ability to reset operational parameters for each channels sounds as a very reasonable solution.

This post is referring to two threads in my site:

6 Channel Version of Super Melquiades

 and

How to USE “Resonating Oops” in loudspeakers

Below in the picture is very cool thing. Right under the 50mV meter there is an actually adjusts the output of Fundamentals Channel.

Surely I do not adjust the output of Fundamentals Channel frequently. In the 3-ch Milq I did it with resistors, setting the balance between MF and Fundamental Channel. Now it is a pure Fundamentals Channel adjustment. It feels different and I believe anybody really, for sake of education, needs to listen a playback with an ability of moderate acoustic output of "second harmonics" at the given frequencies. The volume of the Fundamental Channel should be set precisely for a given room and then the adjustment is not really necessary. Still, without this adjustment a playback from my point of view is losing a very powerful expressive tool.

NBC wrote:

… what do you feel is the upper usable frequency limit for operating your 250Hz tractrix before any negative effects of the horn itself become evident and begin unacceptably compromising the sound…

There is no other rules beside running a channel “A” all the way up and to see where the channel “B” begins to sound at its bottom knee “more interesting” then the channel “A” at its top knee. I have writhe about it many times.

As I wrote before I picked some Vitavox S3 driver.

http://www.GoodSoundClub.com/TreeItem.aspx?PostID=8619

and I was expediting with them recently to use in Fundamental Chanel. My idea was that S3 might care LF knee better then S2. In past I had S3 and I discard in rivalry with S2 as S2 was much more interning in HF region. The ceramic driver of S3 needs different type or amplification that I do not use. However, at that time I did not use Fundamental Chanel.

There are some advantages in S3 design that feel might be beneficial for sub 1K use of S3 drivers. The S3 had more accurately made output channel. I think it shell more benefit FH but who knows… Also, and this is a very big for me the S3 has the diaphragm plate decupled from the back plate. This decupling is very bad thing in S2.

So, I mounted the S3 into the Fundamental Chanel and spent some time to listening this channel. I have to say that I like it but not what I expected. What I expected the S3 does very well – it runs at 600Hz with first order with no “issue” in the bottom region (250Hz Tratrix horn). The next step will be lowering the crossover point to 500-550Hz (that are ultimate objectives) but I need to open the Melquiades amps to do it. What however very much surprised me is the dynamic confidence with witch S3 cares the duty at 600Hz - very imprecise. The S2 was if not dying but really at the very last octave of it’s potency. If I run the Fundamental with S2 at 0dB in relation to MF then I felt it. Since I run the Fundamentals at minus ~ 9dB then the S2 was doing fine. The S3 does have more dynamic balls and it looks like at 600Hz it is still very much not “there”. It would be interning to drop crossover point with S3 at try it in 180Hz-210Hz horn.

I do not have a final decision if I go there. I defiantly will not go for 180Hz-210Hz horn. If I use the S3 then now much I will be able to drop in crossover until my 250Hz hors will feel it. The S3 is shorter then S2, so I would need to re-alight Fundamental Chanel. Still it look like S3 has more power handling at the same frequency, or perhaps it the original “high-pressure” clear diaphragms that my drivers came with. In any cases, the result so far stimulating to stick with S3 for LF region.

Romy wrote :

"...What I expected the S3 does very well – it runs at 600Hz with first order with no “issue” in the bottom region (250Hz Tratrix horn). The next step will be lowering the crossover point to 500-550Hz (that are ultimate objectives)... What however very much surprised me is the dynamic confidence with witch S3 cares the duty at 600Hz - very imprecise. The S2 was if not dying but really at the very last octave of it’s potency. If I run the Fundamental with S2 at 0dB in relation to MF then I felt it. Since I run the Fundamentals at minus ~ 9dB then the S2 was doing fine. The S3 does have more dynamic balls and it looks like at 600Hz it is still very much not “there”. It would be interning to drop crossover point with S3 at try it in 180Hz-210Hz horn...."

There should be no danger in running the S3s down to 500Hz; I am currently running a pair of S2s (same diaphragm as S3) down to 450Hz, 1st order, no problem.

The system is in a room that measures around 80m² with a 3m-high ceiling; in this size room, playing the system loud deos not distress the driver when filtered as described, and there is no evidence of honk at the lower end (the fundamentals channel in my case consists of an S2 into a 180 Hz horn). I should add that this channel is connected to the 8 Ohm taps, while all other channels are all connected to the 16 Ohm taps; the fundamentals channel is hence somewhat attenuated, but not a lot (the 180Hz horn is naturally louder).

Evolution of my own fundamentals channel :

I will now confess, after living with it both ways, to having gone some of the way back toward "misusing" my fundamentals channel.

http://www.goodsoundclub.com/GetPost.aspx?PostID=7760
That is to say, I am for the moment, allowing it to produce a full two octaves, as do all other channels of this system. The pair of drivers is now electronically filtered to work between 450 and 2000 Hz, 1st order (a 18µF cap followed by a 1.5mH coil).

jd*

jessie.dazzle wrote:

There should be no danger in running the S3s down to 500Hz; I am currently running a pair of S2s (same diaphragm as S3) down to 450Hz, 1st order, no problem. The system is in a room that measures around 80m² with a 3m-high ceiling; in this size room, playing the system loud deos not distress the driver when filtered as described, and there is no evidence of honk at the lower end (the fundamentals channel in my case consists of an S2 into a 180 Hz horn). I should add that this channel is connected to the 8 Ohm taps, while all other channels are all connected to the 16 Ohm taps; the fundamentals channel is hence somewhat attenuated, but not a lot (the 180Hz horn is naturally louder).

OK, if it so then my 550-600Hz limitation is not the limitation of S2 driver but my 250Hz horn. This BTW expanse what we have such a differences in assessment of leaking he the S2’s back chamber. (It was somewhere in past). In my case it let it the driver to go 50Hz harder (with some other issues arriving), in your case it was not good as you have a larger hors and there was so “room” for the driver to go down naturally. As I told before: the decision to go for 180Hz was very good on your part and now you are benefited. What is interning is that even in context of my 250Hz horn I do pick some benefits of S3: like higher dynamics at lower region. What would be VERY interning is to run S2 and S3 in 150Hz horn and to see if it possible to load them down to 350-400Hz. I have seen as S2 go apart at 450Hz in open air as the diaphragm-pressing plate is not good in S2. With S2 the diaphragm-pressing plate looks much better and it decoupled from the back of the driver – so I think the S3 will go lover, with no mechanical stress.

jessie.dazzle wrote:

That is to say, I am for the moment, allowing it to produce a full two octaves, as do all other channels of this system. The pair of drivers is now electronically filtered to work between 450 and 2000 Hz, 1st order (a 18µF cap followed by a 1.5mH coil).

Well, it is very legitimate was to do the things. I see a few moments with increase of the low-path up to 2kHz I will outline below.

1)    The Fundamentals Channel at 2kHz with first order pass too much directional HF. Since the 180Hz  is relatively large (twice larger then 250Hz for instance) then the Fundamentals Channel axis will be higher and consequentially the mid lime of the system will be risen at 2kHz much more then at 1kHz. I personally would recommend of lower upper knee crossover point if you drop the lower knee crossover point, but it is only in the case if the minimum integration distance is important. With 80m² room I doubt that it is critical for you.

2)    If the upper knee of your Fundamentals Channel is at 2kHz hen you might not use 450Hz for MF Channel but go for 700-800Hz. This would add some HF extension to your MF channel and will make them MF less beamy.

3)    The biggest this that I see is the flatness of Vitavox drivers over the 1250Hz. Running the driver flat you will have let say  109dB at 500hz and 2kHz but you will have 113dB at 1250Hz. How do you deal with it? Using impedance compensators? Any other means?

Romy the Cat wrote:

There are some advantages in S3 design that feel might be beneficial for sub 1K use of S3 drivers. The S3 had more accurately made output channel. I think it shell more benefit FH but who knows… Also, and this is a very big for me the S3 has the diaphragm plate decupled from the back plate. This decupling is very bad thing in S2.

Among two new Vitavox S3 drivers that I got one was excellent but another was something that I call Black Hole driver. A “Black Hole” driver is a situation when your driver has a fully charged magnet, not open voice coil, not fractured diaphragm but do not produce any sound. So, my second S3 was Black Hole that sucked voltage but returned nothing. That forced me to fix the driver and upon dissecting it I realized that I was wrong presuming that in S3 the diaphragm pressing plate is decupled from the sources of external force – they are not. This is a big foolishness on Vitavox’s side, well it is what it is…. Still, I run S3 on my LF swapper and it goes quite lover then S2 before it become buzzing - a good sign generaly....

Romy wrote :

"...This BTW expanse what we have such a differences in assessment of leaking he the S2’s back chamber. (It was somewhere in past)..."

I would just the same like to confirm my findings one more time in the new room; I will run the test again once I have the system back on the long wall with mid-bass horns in place (had to move it out of the way to make space for bass horn fabrication)

"...As I told before: the decision to go for 180Hz was very good on your part and now you are benefited...."

And as I mentioned before, you can credit yourself with that "right decision" (I made this decision based on Romy's experiences and confessions while adding and integrating the 250 Hz horn to his system)

"...What would be VERY interning is to run S2 and S3 in 150Hz horn and to see if it possible to load them down to 350-400Hz..."

Y E S ! This I would love to try.
Is the S3 as sensitive as the S2?

I keep telling myself that I am almost done making horns, but I keep having ideas to try additional horns (more on that when I finally decide to do it).

"...I have seen an S2 go apart at 450Hz in open air as the diaphragm-pressing plate is not good in S2. With S3 the diaphragm-pressing plate looks much better and it decoupled from the back of the driver – so I think the S3 will go lover, with no mechanical stress..."

Hm... It would probably become clearer to me if I had an S3 to compare with the S2. The diaphragm clamping plate of the S2 is very stout, but yes it is mechanically coupled to the heavy body of the driver (bolted right into it actually) as well as the rear cover.

"...1)    The Fundamentals Channel at 2kHz with first order pass too much directional HF. Since the 180Hz  is relatively large (twice larger then 250Hz for instance) then the Fundamentals Channel axis will be higher and consequentially the mid lime of the system will be risen at 2kHz much more then at 1kHz. I personally would recommend of lower upper knee crossover point if you drop the lower knee crossover point, but it is only in the case if the minimum integration distance is important. With 80m² room I doubt that it is critical for you..."

With the mid-bass horn construction taking so much space, I am forced to sit closer than normal; like about 8 ft... Surprisingly image height has not been as much an issue as I would have thought. But yes, in this configuration the system is more prone to presenting a spacious image. Image height was definitely an issue when I was really "misusing" the fundamentals channel, and running it up a lot higher in the frequency range. The final (in this room) set up will allow something like a max of 16 ft between the listener's head and the mouth of the upper-bass horns.

"...2)    If the upper knee of your Fundamentals Channel is at 2kHz then you might not use 450Hz for MF Channel but go for 700-800Hz. This would add some HF extension to your MF channel and will make them MF less beamy..."

If I understand correctly : With an upper knee of 2 KHz, you are suggesting that I try narrowing the band pass by moving the lower knee up to around 750 Hz (?) Hmmm... Yes I can try it, but it seems more logical to keep the 450 Hz lower knee (I like the body it adds) and to drop the upper knee a bit as you suggest above. As for beaming, I know how unlikely it seems, but I don't have beaming issues.

"...3)    The biggest this that I see is the flatness of Vitavox drivers over the 1250Hz. Running the driver flat you will have let say  109dB at 500hz and 2kHz but you will have 113dB at 1250Hz. How do you deal with it? Using impedance compensators? Any other means?..."

You are saying that the S2 has an increased output around the 1250 Hz range. I don't contest this, but at the same time, I have not measured what exactly the channel is now doing. The current configuration (450 - 2 KHz), was arrived at one night while woking... I just dropped everything and swapped caps and coils in a sort of gut reaction to something I had been trying to identify, which that instant became more clear to me. In the same little frenzy, I brought down the upper knee of the upper-bass horn. The result felt immediately right ... Again, I have not yet taken out the RTA and measured what either channel is now doing. When I do, I will most likely confirm the increased output of the fundamentals channel around the 1250 Hz range, at which point I will of course immediately perceive it as "problematic".

jd*

jessie.dazzle wrote:

Is the S3 as sensitive as the S2?

Yes, they are appearing to be the same sensitively.

jessie.dazzle wrote:

I keep telling myself that I am almost done making horns, but I keep having ideas to try additional horns (more on that when I finally decide to do it).

Do what I did. Stop experimenting with horns and begin to actually USE your playback. If you still have an itch to “think horns” then insult others about their wrong horn moves. It keeps you hands free and fulfills your desire to exercise own findings about what works with horn.

jessie.dazzle wrote:

Hm... It would probably become clearer to me if I had an S3 to compare with the S2. The diaphragm clamping plate of the S2 is very stout, but yes it is mechanically coupled to the heavy body of the driver (bolted right into it actually) as well as the rear cover.

And I very much hate it. I hope you have learned that super tightening of the clamping plate is not always good. However, if I use the still and very heavy Dominus cables then they apply force to the S2/S3 binging posts… that are on the very same clamping plate. It not supposes to be this way. I feel nothing, nether binging posts not the body of the driver shell have impact to the diaphragm pressing plate.

jessie.dazzle wrote:

If I understand correctly : With an upper knee of 2 KHz, you are suggesting that I try narrowing the band pass by moving the lower knee up to around 750 Hz (?) Hmmm... Yes I can try it, but it seems more logical to keep the 450 Hz lower knee (I like the body it adds) and to drop the upper knee a bit as you suggest above. As for beaming, I know how unlikely it seems, but I don't have beaming issues.

What I was trying to say is that if your Fundamental Channel operates before MF Channel. If your Fundamental Channel goes all the way up to 2000Hz then your MF Channel most likely kicks in at higher frequency. If your MF stars at 2000Hz then there is no need to keep it in 450Hz horn. The smaller horn would be better in this case.

jessie.dazzle wrote:

You are saying that the S2 has an increased output around the 1250 Hz range. I don't contest this, but at the same time, I have not measured what exactly the channel is now doing. The current configuration (450 - 2 KHz), was arrived at one night while woking... I just dropped everything and swapped caps and coils in a sort of gut reaction to something I had been trying to identify, which that instant became more clear to me. In the same little frenzy, I brought down the upper knee of the upper-bass horn. The result felt immediately right ... Again, I have not yet taken out the RTA and measured what either channel is now doing. When I do, I will most likely confirm the increased output of the fundamentals channel around the 1250 Hz range, at which point I will of course immediately perceive it as "problematic".

Well, when you go with RTA for each channel then you might see what I mean. Nowadays sufficient RTA solution is very comfortable. For MF range do not need even to be crazy and the regular build-in Laptop’s soundcards are good enough to make rough but in most cases very adequate measurement of response. All that you would need is $50 USB microphone and one of many free software. From certain perspective you do not need even calibration of your mice and your soundcard and you do not care about absolute number but you would need RTA juts to get more or less objective control over relative numbers. Your ears will calibrate the RTA that you are accustomed to use better then anything else. I am sure that people who express long words about loudspeakers would fund what I juts proposed as sacrilege but they need to understand own limitations…

Romy the Cat wrote:

Yes. I’m exiting to see how the new horn I shaping up. Still I do not think that it is about second orders.  Obviously in context of 5 channels system, the more channels one gets then less room between them. I still feel that in order to do it correct my new channel should be no 250Hz but I would say 180Hz-150Hz and then I would still try to for a first order at 750Hz. In the barrow bandwidth satiation as I needed to get out of this driver the second order was God sent but at think point I do not know what kind negative manifestation it would have on overall system presentation. I will be able to see it when I put the second channel in use and tune the crossover more precisely. I went for Bessel Q, 600Hz. Since I have no sensitivity burn I’m searching now for the series air-core coil with DCR of around <0.05R and 8-6ga wires. The Vitavox barbarianism?  Yes, I know the CN458 schematic, opened it up as studied what they were trying to do.  I do not think that it is about barbarianism but about the typical for vintage solution luck of precision, accuracy and exactness. The imaging demands that Vitavox System CN191 had were very restricted, as any other corner loaded system. Also, did you have change to measure a properly installed CN191? I did. I do not have the file now handy but I remember that each channel (!!!) did something like this: Sure, the decision to go for second order in their 330Hz horn was correct but was in beneficial? I do not think so.  Still, generally the compression drivers that run all the way down and crossed at 500Hz never use first order; at least I did not see it. As I told above I never used drivers at 500Hz and now I see why people go for second order in this situation. Interesting that Vitavox when for 500Hz 12dB per octave for thier 330Hz but I do not feel that it is a “secure” cut off and I went for 600Hz 12dB per octave for 250Hz horn… I feel that ~700Hz of their RH330 would be more suitable cut off. The Cat

What I am saying is not a motivation for me to change anything with Macondo but for others, who interested in advancement of the horn system configuration ideas, it might be a useful direction to think and to experiment.

The Cat

Whoever implemented and experimented with my slicing of lower MF range by 3 channels (Upperbass, Fundamentals, and MF) know how powerful it might be. Changing loading and volume of each of the channels it is possible to write any sound one might wish, well if the one knows what to wish. However, recently the game slightly changed and the Fundamental channel got prominence it did not have before. The game change was the DHT driver in MF.

With 6C33C and 6E5P as the MF amplifier the amplitude of the Fundamentals channel was set to benefit the volume of the MF and it worked great. However, all 6C33C sound in a way the same and all 6E5P sound in the way the same. It is not the they sound bad but change from one tube to another did not change the character of MF, so the Fundamentals channel cared about the balance between the volume of MF and Fundamentals.

With the DHT tubes each tube is pretty much own character and the Fundamentals channel not only compliment the  vile setting on MF but also do some very-very interesting compensation, or better to say filling, for the MF. I would say that in some instance it might be +/-  of whole 2dB that Fundamentals channel might output to get the things right. Do not forget that my Fundamentals Channel is very surgical, works in very narrow band (600-1000( and has first order high pass and second (?) order lowpas with one single 6E6P driving Vitavox S3 driver.

What I need at this point is away to calibrate the Fundamentals Channel VERY precisely with 1/4dB resolution. It might be damn costly…

Romy the Cat wrote: