Jump to content
IGNORED

Article: Purifi PTT6.5 Woofer and 1ET400A Amplifier Technology Review


Recommended Posts

On 12/23/2019 at 11:53 AM, all300b said:

Wow - such a great idea to focus on perfecting the 6.5" woofer.  The two-way rises again.  Any thoughts on:

-  What about trying a sealed box configuration?

-  Could this go with a first order crossover to something a little softer - say like an Esotar? The freq response curve for the pure-fi looks remarkably free of of ringing - it might not squeal when asked to play some higher notes.

 

Bryan

 

 

Merry Xmas Bryan. Do you have a box modelling program like Leap or BassBox Pro? Here is a list here if you don't. You would have to enter in the Thiele/Small parameters of the driver into these tools to see if it would work in a sealed box config. Also, you can use Leap to design the crossover to something like an Esotar to see if that would work.

 

Kind regards,

Mitch

Link to comment
13 hours ago, firedog said:

Anyone know if they are going to be selling full kits for DIY? In other words everything you need, just put it together?

 

Merry Xmas @firedog As far as I know, Purifi's plan is to OEM drivers, electronics, PSU's and DSP. There wasn't any mention of selling full kits. The SPK4 and SPK5 plans do include everything to build, but like you say not a kit delivered as a "flat pack."

Link to comment
11 hours ago, blue2 said:

Very interesting article Mitch. Their web site doesn't seem to have much in the way of DIY products just transducers and amp modules. They have the PTT6.5W04-01A (as in your picture) at DKK 2329 (equivalent to $345/£267 + taxes + shipping). Do you have any sales info about the kits you actually tested i.e. price and availability?

d'Appolito DIY kit or just a floorstanding version would be very nice :)

 

Merry Xmas @blue2 What I received is a demo kit for the evaluation of the technology. As mentioned above to firedog, I don't think there is "finished kits" for sale. But I could be wrong and worth a note to Purifi to confirm.

 

Kind regards,

Mitch

Link to comment
5 hours ago, Abtr said:

Great review. Do you think the SPK4 demo speakers will sound better than KEF-LS50's with a sub and a decent active crossover (e.g. at 100Hz and 24dB/oct) to reduce IMD?

 

Merry Xmas @Abtr As an owner of the KEF LS50's and crossed over to dual Rythmik L12 subs with a digital active XO at 100 Hz, they sound really good! Certainly does offload the IMD. As to which one sounds better is a matter of opinion, and how loud one listens, but it is hard ignore the vanishing low distortion of the PTT6.5 woofer...

 

Looking at the measured distortion spec of the LS50 at Soundstage! it comes on pretty quick at 200 Hz. The Rythmik L12's are a good pairing, but maybe dual Rythmik F8's positioned close to the LS50's would offer better even performance as they can be crossed higher e.g. 200 Hz.

 

Kind regards,

Mitch

Link to comment
On 12/29/2019 at 3:08 PM, Lord Victor said:


Very interesting to hear, I personally have a pair of Monitor Audio Platinum 100 and was considering going for a Raidho and Nad M22.2 amp when I saw this, now I’m wondering if this is a better route... for at least the amp or even both...

but if the LS50 can keep up with the Purifi, maybe I should stick with the original plan on the speakers...?


This hobby truly is an enigma, when you can’t ‘try before you buy’!

 

Cheers

 

Agreed. When it comes to speakers, there are two main factors based on the current research out there, mainly by Floyd Toole/Sean Olive and team. One is that the speaker should have smooth on and off axis response (which the LS50's have) and the other his how low you want to go. Of course there are other attributes, but these are the main two that make the difference in most systems. According to Toole's research, bass accounts for about 30% of the factor weighting in subjective evaluations of sound quality. Personally, if I have enough room, I can't live without subs 🙂

 

If you can wait, I would be inclined to see where those Purifi 6.5" woofers end up in a kit and/or commercial product as their woofer is next gen from anything else I have heard. And if it that does not go low/loud enough for you after listening, then maybe subs are in order...

 

Good luck!

Link to comment
5 hours ago, jeffhenning said:

So, a few questions:

• What are you using for correctional DSP?

• Are you using DSP for the crossover of the subs to the mains?

 

Hi Jeff, I use both Acourate and Audiolense DSP. In my current setup, I am using Audiolense to crossover to my dual subs. Audiolense uses linear phase digital crossovers so that they sum perfectly in both the frequency and time domains. Here is a walkthrough of how I did it: https://audiophilestyle.com/ca/ca-academy/ integrating-subwoofers-with-stereo-mains-using-audiolense-r712/  Audiolense also time aligns the subs to mains.

 

Both Acourate and Audiolense are capable for multichannel setups as well. I would have to find it, but I remember one person who triamped their mains, had multiple subs and multichannel setup using Audiolense. Used something like 16 channels...

 

 

I have worked in LEDE studio control rooms before and am I fan 🙂

 

Happy New Year to you as well!

Link to comment

Hi Jeff,

 

As a side note, Acourate and Audiolense can run on a Mac by using Bootcamp/Windows or by using Parallels+Asio4All (Parallels does not support Asio drivers directly). Some folks borrow a PC laptop to take the measurements, design and generate the FIR correction filters, but then host them on a Mac with a convolution engine.

Yes, I am an old school stereo kind of guy, so no surround, except on headphones.

 

Wrt Purifi's drivers and moving mass. You may want to check out Purifi's tech page: https://purifi-audio.com/tech/ and the Dec 10th post on, "A fast driver needs a light cone. Or does it?" Also, Lars had this to say when asked about this, "Essentially, mass mostly affects sensitivity and has nothing to do with speed - a tough myth to bust. The combination of very long stroke and a 4 layer coil adds 10-12g of mass compared to a shorter stroke 2 layer coil. The long stroke surround adds approx 1g more than a conventional shorter stroke half roll and the strengthening of the cone adds perhaps a gram as well. The 4 layer coil increases the motor strength making the driver suitable to work even in small sealed boxes in combination with the strong cone and robust surround (to handle the high back pressure). All of this has not compromised the excellent midrange performance. Or in other words, all of these design choices have resulted in this combination of sub, woofer and mid with ultra low distortion."

 

Hope that helps.

Link to comment
  • 4 weeks later...
7 hours ago, MikeJazz said:

Mitch, I live in an apartment and getting decent bass from a pair of QUAD ESL's is a bit frustrating. I know I would enjoy immensely a full but well defined bass. Lack of definition and articulation in bass is mainly what has stopped me from moving away from ESL's as I found that is not easy to get that quality without investing serious money...

Maybe there is a good solution here.

Mike, could be... these are as good as it gets for a a small cone driver.

Kind regards,

Mitch

Link to comment
  • 6 months later...
  • 1 month later...

Hi @Gavin1977Sorry, I missed your first note. Sound stage depth and imaging are excellent. A little different dispersion characteristics then the LS50, i.e. a bit narrower beamwidth due to the ribbon polar pattern, but other that, a very wide sweetspot. Of course, there is no comparison to bottom end extension or SPL output, the Purifi's are in a league of there own.

Link to comment

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



×
×
  • Create New...