ob (mid range) new driver but fell for the old

0 Members and 1 Guest are viewing this topic. Read 3151 times.

kyrill

ob (mid range) new driver but fell for the old
« on: 18 Feb 2009, 10:23 am »
i just received the P.Audio SN-8mb II ( 8 inch) drivers

they, new out of the box, sound much more transparent with a lot of micro details than
the SABA greencones are  able to deliver. IN a way the P.Audio's do share the fantastic
Focal Audiom 6WM midrange transparency.

but not much depth and there is tendency for some tones to stick to the speaker

So my question is:
Do drivers need burn in time like caps and electronics?
I do not use a passive Xover
So the amp is directly coupled to the speaker

does any one know? Do brand new drivers need playing in time?
« Last Edit: 9 Apr 2009, 06:23 pm by kyrill »

ultrachrome

  • Jr. Member
  • Posts: 48
Re: ob (mid range) new driver
« Reply #1 on: 18 Feb 2009, 04:43 pm »
All sources I've seen have been unanimous and the explanation makes sense.

The spider is made of impregnated cloth and will break in, sort of like a pair of jeans, resulting in a change in the driver's TS parameters.

Method's range from a low frequency sine wave to just playing some dynamic music track over and over.  Preferred break in times seem to start at an hour and go up from there.

The TS parameters can also change when the voice coil heats up so after break in, you might want to make sure the driver has a chance to cool down before measuring.

Or you can just plop it into your baffle and enjoy it.


panomaniac

Re: ob (mid range) new driver
« Reply #2 on: 18 Feb 2009, 06:27 pm »
The P.Audio are pro drivers meant for high powers and high SPls.
It's not likely that you will break them in in a normal, home system  with normal use.

As Ultrachrome says, the spider will want some loosening.  One technique is to run them very hard at Fs because that's were they draw the least current.  And you'll want to do that for many hours.

From what you say about the sound , it seems like you have a healthy rising response.  Can you measure it?

kyrill

Re: ob (mid range) new driver
« Reply #3 on: 20 Mar 2009, 10:31 am »
Hi pano

the DEQX i use takes care of every kind of any not on axix responses of the driver

well

I have played a 100 hrs or so with them and although the sound became more musical the big improvement came when I applied Ennemoser's C37 lacqer. That made already the next day a big improvement.

I forgot that i had C37 on my Focal W6 audiom 6 inch speaker. But this driver could not handle tones under 210 hz in my OB setup. But it sounded so transparent, precise, with nice imaging. The Paudio reached the Focal but with much more lush mid bass. But the imaging is less and if the recording allows, some tones are placed on the cones.
So I try a next avenue the visaton B200 BUT with Ennemoser C37 lacquer. Try it people, buy 50 ml and divide it with 2-3 audiophile friends to share the costs
http://www.ennemoser.com/index.html
the difference is comparable like having a very good line conditioner PLUS vibration/damping control under your gear. the cone gets stiffer, a tick with your nail will sound drier after the application of C39

kyrill

Re: ob (mid range) new driver but fell for the old
« Reply #4 on: 9 Apr 2009, 07:03 pm »
Well

It is some time later and I have learned something about an OB setup. As listening to music is so important for me I cannot stop at just listening. To what i am listening must be realistic in its presentation. I am not the only one. It does not matter how much i love Mahler or Rachmaninoff, Lou Reed, Beau Brummels or Sigur Ross, I cannot listen to them on a mediocre set up or worse on a ghetto blaster.

If  i hear a violin a voice or a bell ringing, it must sound real enough as simulation to fool my brain that it is the real thing i am listening to. This is not an easy accomplishment and there are many diverse ways which will make you happy with this "real enough simulation"

Ob is the way to go but with the proper set up. I have disregarded maybe not justified  the PAudio 8 inch SN-8MB series II. They missed the ehh 3D placement that i need to be fooled. But i replaced them with the B200. Before applying the B 200 in my setup i painted them with 4 layers of C37 violin lacquer ( also did this  but not before placing them but after some days listening, to the SN-8MB and found it to be a big improvement in clarity and micro details).
After 4 days drying I mounted the drivers in my simple OB baffle and used the DEQX to give them in 2 way filter. 60db cut off at 150 hz and 2 khz The Peerless HD tweeter took off after 2 khz ( also 60db/oct) and GR Research servo woofers (4x) took care of the bass.

It was a minor improvement over the PAudio, but was it an improvement? I was very dissappointed> After all i have read many positive stories of the B200 in this circle. I played them in for 5 days non stop with the ISOTEK burning in CD and that improved the sound into more lush, less hifi, more musical. But in no way i could be fooled i listened to the real thing.

How strange, I have very cheap Eltax monitors in my kitchen costing 70 dollars a speaker that sounded more coherent and whole with the DEQX and such a pleasure to listen to and so musical. ( I admit i changed all the cheaply caps in the Xover with Sonicap generation 1) But still??

Then as an experiment as the B200 are essentially sold as a single driver speaker, i Xover with the DEQX at 150 hz and 8kHz and wow... that made the difference. Suddenly the sound became whole for me and my brain happily completed the simulation in a live sounding one.

But how can this be? The DEQX is renowned for its continuous phase correction in real time. So whatever X-over freq. you choose the tweeter will always be in phase with the bass-mid driver over all freqs. So i experimented and found out it was the back wave, the dipole effect that in my case for my brain, that was needed to make the sound whole.

My tweeter is not a dipole so all the sound over 2khz in my original setup, was monopole, not OB at all. It just fired in front of the baffle to me. I dont have a tweeter at the backside of the baffle.
When the B200 took over the high freqs it did broadcast them to the back wall . After playing with the different Xover points  i found the the best sound came when i set the Xover to 4,5 khz ( the diff between 4 or 5 khz was subtle)  . The high tones were much more airier when they came from the Peerless HD. But the sub high tones under 4-5 khz had to be dipole.
Also for some reason when the high tones ( 2-4khz) came from the B200 they had more slam, for some reason more robust, more body dare i say then when at the same loudness coming from the 1 inch tweeter.

So after all i have not judge the Paudio in a fair way. I do need a second back firing tweeter in order to listen to the Paudio well.

But i am a very happy camper at the moment. The B200 is a super midranger . All its rising freqs are tamed by the DEQX and they sound transparent and fast. The sound  in OB is BIG and life like.

I can really imagine how Paul Hynes is happy with his tower of power of 8x B200 a channel. I would urge you Paul to paint them ;)

My listening setup is a modded SB3 with Paul Hynes PWS ( 3.3V and 5V) and digital total mod of Wayne and S/PDIF mod of PAT.
2 highly modded non FB triode PP Jadis tube amps for mid and highs and Servo woofers with servo amps from GR-Research
and Felix (6) with different RC coils for front end or amp duties