Has this speaker expert built and listened to the PTT6.5 personally, or just going by what he sees it labeled as “a long stroke mid bass woofer”? I have built many speakers and listened to over 3 dozen full range drivers out there. Including the highly regarded Scanspeak 10F. The PTT6.5 is special in that it CAN play up to 3.5kHz and play it well. Literally as well or better than many purpose built “mid range” drivers. You could use this driver as a midrange and it won’t disappoint. It is very low distortion and has a great sound. Based on its measurements alone, you can see why it sounds great. This is not a case of “my baby is beautiful because I am the dad” syndrome. It’s really a superlative driver. I would say current top of the line in state of the art.
Here is a measurement in a 10in wide open baffle running full range no filters - looks like a good midrange! No breakups, flat and smooth. You could cross this at 350Hz and 2.5kHz easily as “mid range”:
If you are looking for a design that uses two PTT6.5 per channel, I think the TWW in a TL might be very hard to beat. An MTM is possible too but the TL alignment works better with the drivers closer together. The other option as I mentioned before is a bipole with front and back facing drivers and that will reduce baffle step loss for circa 5dB more sensitivity.
So if I can reassure you, no need for buyer’s remorse. I am going to get an second set because my cabinet maker is keeping the set he supposedly made for me. He is going to be build me a new set.
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At this point you need to seriously consider cutting this guy out and consulting with someone else (if that is what you still wish to do). History is littered with laurel-wreathed fools.
The Purifi woofer is a world-class design and may be the absolute best driver in its size range for many, perhaps even most, applications.
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I'm working up the vindication to jump in and try an LXmini inspired Cardiod with the Purifi 6.5 and tweeter assist. Looking at the rolloff that X posted above, 380Hz 1st order seems reasonable, and therefore a transient perfect passive LXmini. I think the OB would be offset back ~8" with no DSP delay though
Forane, any details on the XO or slopes, and which viawave?
Forane, any details on the XO or slopes, and which viawave?
- Hi guys, thank you Everyone who contributed - xrk , stretchneck , 454Casull , Forane12 , you all made Very good points, and this is very reassuring.
- also thanks for the link - great article.
-- In thinking about it, I guess we all have our blind spots and opinions about how things work... and it's easy to dismiss other peoples ideas without making sure we are right.
I would guess that probably goes Double for person that has designed great speakers for most of their adult life.
- The comments here dredged up some memories of other conversations I've had with other speaker designers , about speaker design in general that I've had in the past at Audio Shows.
- I remember one designer who's top of the line speaker had one some awards, and I had been lucky enough to have bought a year or two before and really liked. Out of the blue when I was at an Audio Show I had the chance to meet him. I was so excited to meet him and ask some questions about the design. We talked for quite awhile, and were having a great time , up until the point where one of my questions really put the breaks on the conversation.....
I asked if money wasn't an object what would he do to improve the design, because most speakers are built with a budget in mind , weren't they? -- So when I asked that question he just sat there with a funny look on his face for about thirty seconds, then he said he couldn't think of anything......... But being the eager beaver I said well what about the crossover did it have the best parts in it or should I maybe buy some better capacitors for it? ...........
Then he said that Maybe I might try putting a little better cap as a bypass cap on the tweeter... but that he didn't believe there was really any difference in capacitors and he thought I was wasting my time . . . . . . I was quite surprised to hear that, at least from a famous speaker designer, because I had read about other speaker designers who had said the exact opposite thing. -- just goes to show , everyone has there own opinions I guess.
- also thanks for the link - great article.
-- In thinking about it, I guess we all have our blind spots and opinions about how things work... and it's easy to dismiss other peoples ideas without making sure we are right.
I would guess that probably goes Double for person that has designed great speakers for most of their adult life.
- The comments here dredged up some memories of other conversations I've had with other speaker designers , about speaker design in general that I've had in the past at Audio Shows.
- I remember one designer who's top of the line speaker had one some awards, and I had been lucky enough to have bought a year or two before and really liked. Out of the blue when I was at an Audio Show I had the chance to meet him. I was so excited to meet him and ask some questions about the design. We talked for quite awhile, and were having a great time , up until the point where one of my questions really put the breaks on the conversation.....
I asked if money wasn't an object what would he do to improve the design, because most speakers are built with a budget in mind , weren't they? -- So when I asked that question he just sat there with a funny look on his face for about thirty seconds, then he said he couldn't think of anything......... But being the eager beaver I said well what about the crossover did it have the best parts in it or should I maybe buy some better capacitors for it? ...........
Then he said that Maybe I might try putting a little better cap as a bypass cap on the tweeter... but that he didn't believe there was really any difference in capacitors and he thought I was wasting my time . . . . . . I was quite surprised to hear that, at least from a famous speaker designer, because I had read about other speaker designers who had said the exact opposite thing. -- just goes to show , everyone has there own opinions I guess.
- Hi DaveFred , this was around 1998 - 2000 in Los Angeles California , it was the first Audio Show I had ever been to, I think it was put on by Stereophile Magazine, and I had just bought a pair of NHT 3.3 Loudspeakers.
I was downstairs at lunch time and I recognized Ken Kantor sitting at a table so I went over and struck up a conversation with him. He was a great guy and I really enjoyed talking to him, but I was very surprised by his comment at the time. I don't know if he still feels the same way or not these days.
I have heard from several other NHT owners that he is still a great guy and has helped a number of them who have run into problems over the years. It has mostly been trouble with blown drivers and such. Those speakers can really play at Rock Concert levels if you want to - and sound great doing it! But like everything else they need their owners to really feed them clean power if their going to try that.
- I do know that I have really enjoyed those speakers over the years, and I kept them in Mint condition, although, I did just need to replace the foam that ran along next to the Tweeter and Midrange because the original stuff eventually falls apart. I replaced it with the best natural soft wool/felt that I could find - looks better than the original, and should outlast it too.
I just sold the NHT 3.3's along with my VTL Deluxe MB300 - 300 watt Monoblocks on Thursday to a nice guy who drove down from Oklahoma to listen to them... Every time I walk by the empty space now I get a touch of sellers remorse - LOL
I'm going to miss them both, but it was time to move on in life - hopefully with some of the great help I get here on this forum and others I will be able to build better....
My main goal was to change part of my set up to High efficiency speakers and small tube amplifiers that I can build myself............. but then I got sucked into this Group buy -- LOL - LOL - LOL
- So now I'll need to find a good 100 to 300 watt amplifier again - - I think it's pretty funny -- or maybe more ironic......... but I will probably look at some of the new Class-D stuff for the speakers that will be using the Purifi Audio drivers, not sure yet.
I was downstairs at lunch time and I recognized Ken Kantor sitting at a table so I went over and struck up a conversation with him. He was a great guy and I really enjoyed talking to him, but I was very surprised by his comment at the time. I don't know if he still feels the same way or not these days.
I have heard from several other NHT owners that he is still a great guy and has helped a number of them who have run into problems over the years. It has mostly been trouble with blown drivers and such. Those speakers can really play at Rock Concert levels if you want to - and sound great doing it! But like everything else they need their owners to really feed them clean power if their going to try that.
- I do know that I have really enjoyed those speakers over the years, and I kept them in Mint condition, although, I did just need to replace the foam that ran along next to the Tweeter and Midrange because the original stuff eventually falls apart. I replaced it with the best natural soft wool/felt that I could find - looks better than the original, and should outlast it too.
I just sold the NHT 3.3's along with my VTL Deluxe MB300 - 300 watt Monoblocks on Thursday to a nice guy who drove down from Oklahoma to listen to them... Every time I walk by the empty space now I get a touch of sellers remorse - LOL
I'm going to miss them both, but it was time to move on in life - hopefully with some of the great help I get here on this forum and others I will be able to build better....
My main goal was to change part of my set up to High efficiency speakers and small tube amplifiers that I can build myself............. but then I got sucked into this Group buy -- LOL - LOL - LOL
- So now I'll need to find a good 100 to 300 watt amplifier again - - I think it's pretty funny -- or maybe more ironic......... but I will probably look at some of the new Class-D stuff for the speakers that will be using the Purifi Audio drivers, not sure yet.
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If you are planning on building with the Purifi driver then why not use their Amp?
EVAL1 - PURIFI
Getting good reviews and is a rival for the Hypex NC500.
Or just go active with a Hypex FA Plate amp with built in dsp for crossover, delay and smoothing.
EVAL1 - PURIFI
Getting good reviews and is a rival for the Hypex NC500.
Or just go active with a Hypex FA Plate amp with built in dsp for crossover, delay and smoothing.
I have owned NC500 and presently 1ET400. Both sound great. I no longer have the NC500 monos, but I enjoyed them very much. Purifi modules are obviously 3rd gen, but they have the same signature. Without both of them being side by side for comparison don’t think I could accurately describe the differences to you to be honest.
It seems to be very little room to come with some criticism in this thread but I’m going to give it a try. Regarding weight of the cone and BL my findings are that it matters a lot in terms of midrange openness and dynamics.
I built the tl as very nicely presented by Xrk with the PTT6.5. Several versions of crossover was tested. With more and less bsc and at different frequencies to meet the tweeter. All versions came out with a bit closed and boomy sound.
Finally I swapped to accuton c173-6-191e in the same box just to try. This comparison didn’t come out in favor of the Purifi driver. Another driver I compared with is the Phl1220 which brings more snap and liveliness and is, in my ears, on par with the accuton.
This is of course my personal opinion. Each to their own. The Purifi is a very bass capable driver, low distortion and you can play loud without it changing its character.
I built the tl as very nicely presented by Xrk with the PTT6.5. Several versions of crossover was tested. With more and less bsc and at different frequencies to meet the tweeter. All versions came out with a bit closed and boomy sound.
Finally I swapped to accuton c173-6-191e in the same box just to try. This comparison didn’t come out in favor of the Purifi driver. Another driver I compared with is the Phl1220 which brings more snap and liveliness and is, in my ears, on par with the accuton.
This is of course my personal opinion. Each to their own. The Purifi is a very bass capable driver, low distortion and you can play loud without it changing its character.
- Hi xrk, Sorry I forgot to respond to your question, as far as I can tell I don't believe he has heard the drivers, he only commented twice that it weighed too much to be a good midrange, and the other thing he said that he knew someone reviewing a demo speaker who said the woofer didn't sound good reaching all the way up to the ribbon. -- I don't know who the reviewer is but, he is the only " reviewer " that has felt that way.
- Hi guys, I'm not sure if you all seen this or not , I Found another Active crossover option that is supposed to be a real step up from miniDSP , and Behringer active crossovers, they are small and appear to be well made, and very inexpensive too. Their from a company called Xkitz, they offer either 2way or 3way options. They have advantages and disadvantages - It is All Analog for a simpler/cleaner set up for vinyl users.
* All Analog Design
* High quality Linkwitz-Riley crossover, Constant Voltage, 4th order,
24dB/Octave
* The crossover frequency configuration components are located on a single
socketed module – it’s very quick and easy to change the XO frequency by
simply plugging in a new module
-- One thing that's nice is that it comes with separate Baffle Step correction
too.
* Here is a short video on the product being tested by Joseph Crowe,
--https://www.youtube.com/watch?v=4YhY1qZ2cgc&ab_channel=JosephCrowe%27sDIYSpeakerBuilding
And here is the website,
-- Xkitz Electronics
* All Analog Design
* High quality Linkwitz-Riley crossover, Constant Voltage, 4th order,
24dB/Octave
* The crossover frequency configuration components are located on a single
socketed module – it’s very quick and easy to change the XO frequency by
simply plugging in a new module
-- One thing that's nice is that it comes with separate Baffle Step correction
too.
* Here is a short video on the product being tested by Joseph Crowe,
--https://www.youtube.com/watch?v=4YhY1qZ2cgc&ab_channel=JosephCrowe%27sDIYSpeakerBuilding
And here is the website,
-- Xkitz Electronics
If you want an analog crossover why not go for the Pass designed one?
DIY Biamp 6-24 Crossover – diyAudio Store
I'm all for choice and going for what you are comfortable with but I would not consider what you are discussing as a 'step up'.
DIY Biamp 6-24 Crossover – diyAudio Store
I'm all for choice and going for what you are comfortable with but I would not consider what you are discussing as a 'step up'.
Correlation is not causality. It didn't work for you and you blame the cone mass, but you don't actually know if that was the case.
@hallcon83: Quite a sweeping statement, considering what is possible using minidsp (or similar) digital out, with good quality DAC. the linked modules look OK for what they are, but I also wouldnt consider them a step up; not in the slightest. If high quality analogue input is required; match with a high quality ADC. the idea of using pre-set filter modules seems kind of arbitrary IMO.
