Watched that yesterday great video and very true you have to measure your drivers to get the best sound . Be curious to see Danny Richie put it through it's paces . I appreciate the opinions I think for a high end active compact these PTT are going to be killer I still would like the SB Dome midrange in there as well however if that proves to be not very impressive then I guess it is PTT all the way .
Do any company's offer really good driver matching , testing and sale's like North Creek Audio used to ? Seas has shown ordinary pair matching lately
People always seem to get this wrong. Just like the amplifier brings the cone into motion it also brings it to a stop. The amplifier and motor are continuously moving the cone back and forth through the zero crossing. It can easily bring it to a stop at the zero crossing if that's what the music dictates.
And yes, when a transient occurs within the music the decay of said transient, either down to nothing, or to quieter parts is actually part of the music.
Good point I could just use the dual NHT XDA bass systems that I have 2 active opposing 10 inch Seas a side and just go with a simple 2 way and save a ton of money on extreme cabinet build.
Great statement
The only way (as far as I know) to have full control is to allow the amplifier to have full control (active) and with a decent DF of >100. I am sure lots of people will claim that they like the flavor passive components add but if we are talking superior performance, neutral or naked rendition, then passive components cannot compete. Not only that, the benefits of active should be more evident as the temperature of the inductors and voice coil starts to do its thing. Lock in the FR response and bandwidth before the signal is amplified. The cabinet play a huge role as well, but that is for another debate I've always found it helpful to envision a speaker as a "spring centered position servo". That is, it's job is to position the cone according to the (constantly changing) output voltage of the amplifier, making it a servo not a motor.
Ha, interesting. I have a pair of the Xd monitor tops that I'm currently figuring out what to do with. I would have loved to get a set of the bass modules, but if those were ever available during the closeout firesale they were long-gone by the time I got engaged.
The Xd monitors work very well on top of RSS210hf woofer modules crossed around 200Hz. I'm running passive xovers on the Xd and active to the Daytons. I have a minidsp SHD that I need to get set up to drive this system, and then decide whether to leave it in this form or get ambitious and rebuild the drivers into something new - I'm aspiring to something like the Sonus Faber Elipsa form factor. (probably with RSS256HO replacing the 210 if I go that way)
In the context of the PTT, I get drawn in to the idea of higher end drivers, but then go back and remind myself just how good the Seas Excel sound and wonder whether it's really worth getting wound up over wanting to upgrade.
I wish I got some on closeout ! These were expensive in Australia sad the project folded they were achieving great things. And yes those drivers in that system were incredibly clean and with the 2 bass modules fabulous- you maybe right the PTT needs the support of a really good cabinet was thinking of solid Aluminium to get the silent background that these drivers appear capable of
I see you found my preliminary boxing match with the quad I have. I really was disappointed in the matching Seas employed, meaning lack thereof. I'm just glad I was able to sort it out.
In most cases, there is a phase plug of sorts to block the ultrasonic resonance on a metal dome. Unfortunately, the 27TAC does not have that. I might try measuring it with and without the felt-dot on the center and see what happens, or even try an ultrasonic notch of sorts; again- just to see.
It is also interesting to see Mr. Gerhard found it registered lowest on the HD scale of his personal testing. This really gives me high hopes of what I plan to do with it.
Later,
Wolf
I am going to save you some money here. Forget Aluminium (6083 which many use. Airplane grade aluminium is not a technical description, its invented to add value of the material, aka BS
). Read both links and you should have a much better understanding of which material(s) to choose.damping factor values - audio qualia
The Virtues of Panzerholz : An Investigation into the Acoustical Properties of Aluminum and Panzerholz
To make life easier, you can look at Density and Tensile Strength when it comes to materials, they have a corelation when it comes to damping factor of the material.
Look at Bliesma, non of his tweeters have that bad of a cone breakup and it does not have phase plug. SB's aluminum does but not their Be. Saying that, most AlMg tweeters have this issue, I think what is saving Bliesma T25A-6 is that the peak is at 32kHz... which should be enough to create decent IMD bellow 20kHz.
I'm going to correct/clarify something- I purchased them, they weren't just sent my way to test. I had an idea for a project with these, and did some measuring and shared my thoughts. There will be more information to come as I progress...
I'm glad you found the information useful!
Look at Bliesma,
Most of the Bliessma tweeters are out of my price range for drivers, and they are harder to source. The thickness/profile of the Bliessma tweeters' domes is likely what is shifting this resonance north, aside from material implementation.
They use a different dome than any other manufacturer.
Later,
Wolf
1. The T25A-6 is marginally higher in price compared to SEAS 27TAC/GB. A pair of T25A-6 will set you back €260 while the 27TAC/GB is €220 .. might depend on retailer.
2. Correct. The base of the dome has more material than the top which all in all is more pistonic, quite clever.
I am going to save you some money here. Forget Aluminium (6083 which many use. Airplane grade aluminium is not a technical description, its invented to add value of the material, aka BS
damping factor values - audio qualia
The Virtues of Panzerholz : An Investigation into the Acoustical Properties of Aluminum and Panzerholz
To make life easier, you can look at Density and Tensile Strength when it comes to materials, they have a corelation when it comes to damping factor of the material.
Yes read that however Panzerholz in Australia is dearer than a 747 jet and I have 4 cousins who are Fitters and Turners,toolmakers and engineers and no one skilled in woodworking! So braced,lined Aluminium will have to do . I was thinking of Concrete but better off using what I can access. Also the bits worn out cutting and shaping Panzerholz was reading on German forum over a 1000 euros to cut the baffle and he was the owner of the shop. I guess you would have read that project, I cannot remember the link but his speakers were incredible .I am in no rush so plan on seeing how these PTT go in systems - before these I was planning on a SB Textrene build so that still maybe the way to go . I will be watching you expert's to see what can be achieved 😊
Thanks Wolf It was very useful and i take my hat off to you taking apart drivers and trying to improve them i think a full refund would have been my strategy. I think Seas have slipped since takeover the differences you discovered inside were just not good enough at that price I will be following your progress with great interest
Cheers