I found with the Altec 414 that it was worthwhile lowering the energy going into the woofer at break-up frequencies- the earliest sitting at 2300Hz for the 414. I tried notching peaks out but that sounded off. So then I went with a Zobel+6db/oct filter and crossing over from 500-1700Hz worked. I found that the ideal point was first of all related to the relative quality of the higher frequency driver near the crossover frequencies (a more important question that just running full range). Where I saw the most synergy, was by choosing the crossover points so that its attenuation coincides roughly with the gains of the baffle kicking in, which minimise the complexity of the crossover - something that is probably why one would try a x-over-less LF, and minimal filter would be its (better) alternative. So in conclusion for me, having a tweeter that can take over low, allows you to simplify the filtering and avoid the break up modes being audible plus deal with the baffle step loss... note how Janos' filter for Altec 515/288 and features of his VOL design allows a very simple filter.
Previously you recommended the Cube Audio FC8 drivers. It looks like they retail about $2000 per pair. Parts Express sells a similar 8” driver for about $600 per pair. It’s a big difference in price. but is it a significant difference in sound?
What is the effective band product of the Altec driver? Voigt pipes are pretty straight forward. 1/4 wavelength of drivers Fs. Put approximately a 7 degree angle to the box. Make it the width of the driver. Place the driver at the golden mean and you have a great start point.
The 515 series can be used up to 1.6kHz (as in the 604), but then the LF is limited at 35-45Hz or so depending on the cabinet / room alignment etc. Limiting to 800Hz we can get 30Hz or a little lower, and limiting to 500Hz it can reach down to below 20Hz. I'm using my 515C with a 240Hz 1st order crossover and it reaches down strong to 15Hz (18Hz tuned port/mass loading shuts down at 11Hz). There's very very little available music that uses creatively the sub-20Hz region - but it's well worth it, it is something like a next level revelation.
@@realworldaudio Would need the T/S parameters to see how well suited it is for a horn/pipe. Qes / Fs gives you the EBP. If it’s higher that 150, then it could work well in a pipe. Problem is, it would be huge…
@@IvoTichelaar Oh, I know :) I built a BiB enclosure for my Fostex FE168Ez drivers. 1/2 wave pipe. It’s 6’ tall, folded. Also built a 1/4 wave pipe for my Fe126En drivers. Also 6’ tall, but occupies much less visual space in my listening room.
I am puzzled by your suggestion that a voigt pipe cannot be adequately simulated. hornresp, akabak, AJhorn, they are all available and validated in the outside world. It's just like the other quarter wave enclosures.
Yes, it can be extremely well simulated with computer models. However, the computer models tell very little about how our brains hear it. I have heard many many pipes optimized by computer simulations and they were... okay, and none poorly. I heard pipes built without simulations, and they ranged from poorly to okay. The ones I designed based on Derek Walton's pipe following my guts are a blast. Not just by my opinion (which should not really count as they are my babies), but by people who compared it to other pipes - I consistently got reports that my pipes were in another league. I think computer simulations are very useful to give a better understanding, and help when one is stuck. Eduard used computer models to fine tune his Voice of Lancelot, and it worked superbly. I just don't want to have people chase models blindly. In my experience the vast majority of VP builders are too much focused on models. Not a bad thing, but need to open up a little to access the full potential of the pipes.
To my understanding a voight pipe resonates the air in the pipe. But a horn moves the air in a pipe. Both then use room loading from the mouth to achieve bass. If both had the same size mouth i assume a horn would be superior? Would you agree?
If both had an 8m / 25ft wide mouth, then the horn would be a lot better. As that is not a practical size for most homes... with realistic mouth sizes the horn is way more efficient, but its frequency range is excruciatingly limited vs the VP. With same size mouth (as is actually in the VP) the VP works at 95dB sensitivity down to 30Hz while an equivalent horn would be 105dB down to 1kHz. Not even reaching lower midrange. The VP is an incredible solution to have wide frequency range at a much higher sensitivity than a conventional box.
@@realworldaudio Ty. I really appreciate the reply. I find that low Qts speakers are peaky in the 2-4khz range. I really hate peaky speakers and so actually prefer speakers with a higher Qts, say 0.5 - 1.5? What Qts would you say is desirable for a voight pipe? And what is the cut off point in Qts where they cease to perform. Ty
Do you think there is any advantage by moving the crossover components closer to the amp? I use non-terminated copper wire for speaker wire, bulk, so I can put the crossover components anywhere between the driver and amp output terminals. I can even put space between each crossover component along the entire speaker wire! Would spacing the crossover components along the speaker wire enhance the performance of each cap, resistor and coil? Or do the components by design only work as a cluster packed together?
@@realworldaudiointeresting result, that the bandwidth of the speaker wires is increased. I’m a little confused since the function of the crossover is to restrict bandwidth. Regardless, I will still try moving the crossover closer to the amp. Thank you! I’ve been looking for data that shows separating the crossover components along the length of the speaker wire has sonic advantages. I have already heard external crossovers, that stuff is never going back inside the box.
Interesting question. Would want to look into it…. Here’s my “knee jerk reaction”. As a crossover is a dividing network, as much as the signal is “purified” by a crossover (proper frequencies going to proper driver), is also a signal reducer, as the whole signal gets split. I would think, you would want the full signal going as close to the driver as possible before separating it out. I like having the crossover inside the box as it helps to “scatter” the waves inside the box. Symmetry is bad for speakers…
Interesting idea, but it will will be for ever confined to the DIY section of the audio hobby. No speaker manufacturer will want to deal with audiophiles wiring up the cross over network the wrong way.
I found with the Altec 414 that it was worthwhile lowering the energy going into the woofer at break-up frequencies- the earliest sitting at 2300Hz for the 414. I tried notching peaks out but that sounded off.
So then I went with a Zobel+6db/oct filter and crossing over from 500-1700Hz worked. I found that the ideal point was first of all related to the relative quality of the higher frequency driver near the crossover frequencies (a more important question that just running full range). Where I saw the most synergy, was by choosing the crossover points so that its attenuation coincides roughly with the gains of the baffle kicking in, which minimise the complexity of the crossover - something that is probably why one would try a x-over-less LF, and minimal filter would be its (better) alternative. So in conclusion for me, having a tweeter that can take over low, allows you to simplify the filtering and avoid the break up modes being audible plus deal with the baffle step loss... note how Janos' filter for Altec 515/288 and features of his VOL design allows a very simple filter.
Hi Eduard, welcome back.
Hello Eduard ...i have no longer notifictuions on your channel.....?
@@frankgeeraerts6243 There were no updates this year yet... that's probably why
Thanks for answering my question. I tried it on my 416 8c and your opinion matches what i heard aswell. Also the bass went very weak. Thanks.
Previously you recommended the Cube Audio FC8 drivers. It looks like they retail about $2000 per pair. Parts Express sells a similar 8” driver for about $600 per pair. It’s a big difference in price. but is it a significant difference in sound?
Just shot the video answer, will be coming out soon! Needs editing & combining with the sound ;
What is the effective band product of the Altec driver? Voigt pipes are pretty straight forward. 1/4 wavelength of drivers Fs. Put approximately a 7 degree angle to the box. Make it the width of the driver. Place the driver at the golden mean and you have a great start point.
The 515 series can be used up to 1.6kHz (as in the 604), but then the LF is limited at 35-45Hz or so depending on the cabinet / room alignment etc. Limiting to 800Hz we can get 30Hz or a little lower, and limiting to 500Hz it can reach down to below 20Hz. I'm using my 515C with a 240Hz 1st order crossover and it reaches down strong to 15Hz (18Hz tuned port/mass loading shuts down at 11Hz). There's very very little available music that uses creatively the sub-20Hz region - but it's well worth it, it is something like a next level revelation.
@@realworldaudio Would need the T/S parameters to see how well suited it is for a horn/pipe. Qes / Fs gives you the EBP. If it’s higher that 150, then it could work well in a pipe. Problem is, it would be huge…
@@realworldaudio The length of 25hz, is 13.72m. So the Voigt Pipe would have to be 3.43m tall. Not very practical…
@@ThePerkri you can fold the pipe. I have a 480cm pipe horn standing in my living room, it's folded once.
@@IvoTichelaar Oh, I know :) I built a BiB enclosure for my Fostex FE168Ez drivers. 1/2 wave pipe. It’s 6’ tall, folded. Also built a 1/4 wave pipe for my Fe126En drivers. Also 6’ tall, but occupies much less visual space in my listening room.
I am puzzled by your suggestion that a voigt pipe cannot be adequately simulated. hornresp, akabak, AJhorn, they are all available and validated in the outside world. It's just like the other quarter wave enclosures.
Yes, it can be extremely well simulated with computer models. However, the computer models tell very little about how our brains hear it. I have heard many many pipes optimized by computer simulations and they were... okay, and none poorly. I heard pipes built without simulations, and they ranged from poorly to okay. The ones I designed based on Derek Walton's pipe following my guts are a blast. Not just by my opinion (which should not really count as they are my babies), but by people who compared it to other pipes - I consistently got reports that my pipes were in another league.
I think computer simulations are very useful to give a better understanding, and help when one is stuck. Eduard used computer models to fine tune his Voice of Lancelot, and it worked superbly. I just don't want to have people chase models blindly. In my experience the vast majority of VP builders are too much focused on models. Not a bad thing, but need to open up a little to access the full potential of the pipes.
You're right Janos.........this Altec driver is essentialy a midbass driver , a friend uses this one for this purpose in a four way set up .....
And what a midband driver it is! Loveliest, most authentic human voices I heard. :)
To my understanding a voight pipe resonates the air in the pipe. But a horn moves the air in a pipe. Both then use room loading from the mouth to achieve bass.
If both had the same size mouth i assume a horn would be superior? Would you agree?
If both had an 8m / 25ft wide mouth, then the horn would be a lot better. As that is not a practical size for most homes... with realistic mouth sizes the horn is way more efficient, but its frequency range is excruciatingly limited vs the VP. With same size mouth (as is actually in the VP) the VP works at 95dB sensitivity down to 30Hz while an equivalent horn would be 105dB down to 1kHz. Not even reaching lower midrange. The VP is an incredible solution to have wide frequency range at a much higher sensitivity than a conventional box.
@@realworldaudio Ty. I really appreciate the reply. I find that low Qts speakers are peaky in the 2-4khz range. I really hate peaky speakers and so actually prefer speakers with a higher Qts, say 0.5 - 1.5? What Qts would you say is desirable for a voight pipe? And what is the cut off point in Qts where they cease to perform. Ty
Do you think there is any advantage by moving the crossover components closer to the amp? I use non-terminated copper wire for speaker wire, bulk, so I can put the crossover components anywhere between the driver and amp output terminals. I can even put space between each crossover component along the entire speaker wire! Would spacing the crossover components along the speaker wire enhance the performance of each cap, resistor and coil? Or do the components by design only work as a cluster packed together?
Yes, there is definitively! Closer to the amp, the better. It increases the bandwidth of the speaker cables a lot. ;
@@realworldaudiointeresting result, that the bandwidth of the speaker wires is increased. I’m a little confused since the function of the crossover is to restrict bandwidth. Regardless, I will still try moving the crossover closer to the amp. Thank you! I’ve been looking for data that shows separating the crossover components along the length of the speaker wire has sonic advantages. I have already heard external crossovers, that stuff is never going back inside the box.
Unless frequency response and bandwidth are different. I have to do some research. Thanks!
Interesting question. Would want to look into it…. Here’s my “knee jerk reaction”. As a crossover is a dividing network, as much as the signal is “purified” by a crossover (proper frequencies going to proper driver), is also a signal reducer, as the whole signal gets split. I would think, you would want the full signal going as close to the driver as possible before separating it out. I like having the crossover inside the box as it helps to “scatter” the waves inside the box. Symmetry is bad for speakers…
Interesting idea, but it will will be for ever confined to the DIY section of the audio hobby. No speaker manufacturer will want to deal with audiophiles wiring up the cross over network the wrong way.
Here's the GPA link for the 515B datasheet shown: greatplainsaudio.com/wp-content/uploads/2017/07/515b-1.pdf
That's a great website, I bookmarked it immediately.