[woodsyi]

I better tread carefully hear since I am in someway pitting Brian at VMPS, Bill at Response Audio and vicariously Bob from SP Tech. Right now I am breaking in a pair of Bella SP/AV1s with a pair of Hurricanes.  I plan to eventually move these to my bedroom to replace a pair of BOSE speakers.  They are fully loaded with all the bells and whistles Bill could think of.  With the V-caps, autoformers and a well shielded umbilical for the external crossover, it will take a while to burn these in.  I know from my experience with V-caps in my amp.  The first impression is that they sound very clean. They play well at all volumes.  They sound a little hot out of the box but they should settle down.  Curiously, some of the perceived brightness of the tweeter went away when I hook up the subs.  I lowpassed the subs at 50 Hz to augment the Bella/SP1's running full and they sound better.  I quess psychoacoustics does matter.  I will continue to burn these in for awhile then post some impressions and comparisons.

[Bill Baker]

Curiously, some of the perceived brightness of the tweeter went away when I hook up the subs. I lowpassed the subs at 50 Hz to augment the Bella/SP1's running full and they sound better. I quess psychoacoustics does matter.

 Hello woodsyi,
 First...... thanks for posting initial impressions.
 It's interesting that you mention the "perceived" brightness as this is something to be considered when looking at any non-fullrange system. When the lowest frequencies are missing, many will condem the speaker of being bright. When a sub is introduced to balance out the system, the "perception" is much different.

 There are many smaller speakers that sound well balanced without the sub, introduce a sub with these speakers and some will conclude the upper end is now rolled off.

 Most bookshelf speakers are designed with the idea that a sub will be used and balance out the system therfore coming across as a bit aggressive up top. For this reason, I feel it is a good idea to have adjustable attenuation for the tweeter to accomidate the application.

 Woodsyi, if you are not going to be using a sub with these speakers when they reach their final application, we can very easily adjust for this within the crossover simply by changing the attenuation resistors for the tweeter. However, we must be careful not to go to far as that tweeter starts in at about 1kHz and we don't want to effect the midrange too much. It's very easy to do and if you decide to do so after the full break in, I can supply you with the proper resistor. It will take longer for your soldering iron to heat up than it will to change the part.

 Keep us [me] posted on your thoughts as the speakers get more hours on them.

[audiojerry]

Also bear in mind, that as the Bella's burn in, after about 100 hours the bass frequencies will come in much stronger than what you are likely getting right now. This will really help to give body to the tonality, and the perceived brightness of the tweeter.  

You will be pleasantly surprised.

Just be patient  

[LAL]

You have had these for several weeks, I am curious about your evaluation of them.

LAL

[woodsyi]

I am still breaking in the Bellas.  I have external x-over (thick shielded umbilical) with autoformers and Bill used V-caps on the x-over.  I have been told they need a lot of break in time.  I know from my amps that V-caps take  a while breaking in.  So, I want to make sure the speaks are fully cooked before I compare them.  Just to tease you a little, there is a difference.........

[Bill Baker]

Just to tease you a little, there is a difference.........

 That's not teasing. There should be a difference. Want to tease em'

 " The differences are......."

 All Bella customers to date are stating that about 300 hours is the mark. The upper end should reach it's fullest potential by this point where the bass whould come around at the 200 hour mark or so.
 Everything else should be good to go by time to reach that 300 hour mark.

 Do keep us posted.

[woodsyi]

I realized that the rate I was going to break these in it would be 6 months before I would feel comfortable discussing the sound.  So, I hooked them up to an old tuner and an old integrated amp out of phase and put them up facing each other.  It's neat to hear sound cancellation at work.  They have been on for 4 days.  Another week and they just may be fully cooked just in time to be heard by some discerning ears.

[woodsyi]

It's a hard thing, at least to me, to compare speakers when you have to disconnect one pair, turn the tube amps off, change speakers, then turn amps back on and wait for the tubes to restablize before listening.  It just makes it impossible to do an AB test with your short term memory in tact.  So instead, I have been listening to each set of speakers for days on just enjoying them.  To be fair I have been listening to the AV/SP1s augmented with 2 Largersubs lowpassed at 50 Hz.  

     I like the Bella speakers.  From the get go, they were very clean to the point of being lean.  Initially, I couldn't listen to Judy Collins because she was just too monotonous and single pitched to the point of annoyance even with 6SN7 preamp and KT 88 tube amps with 6SN drivers in the chain.  I also used Iliana Cortrubas, Annie Haslam and Maria Callas (vinyl only for her since she is unlistenable on CD) for my test listening.  They have difficult voices to reproduce nicely, but Bellas have now filled out and reproduce them quite nicely.  I would characterize these speakers as neutral and accurate but with some extra mojo that makes them special.
     I don't know much about the acoustics of flutes, but I tell you that these speakers do open air pipes and flutes in a glorious way.  From flutes, panpipes to Shakuhachi, the Bella SP/AV1s resonate harmonics of these open air pipe instruments like no other I have heard.  A poignant passage invokes that pang in your heart to a point of ache like an unrequited love you felt as a teenager.  I have never heard them like this before.  In the same way the vocal texture of female singers are presented with pleasingly warm timbre.  The notes are still clean and accurate, but now the vibratos and harmonics of the voices are blended in a evocative way.  Turn the lights off and the glows of the tubes and the airy voices transport you into the heart of music.  Just what I want for a bedroom set.  The micro dynamics of these speakers are exceptional.

[audiojerry]

That's exactly what I experienced with them.
Anyone else who's reading this and are considering the Bella's need to understand this, and just be patient and give them lots of time to burn in.

[Bill Baker]

Thanks for the kinds words woodsyi and audiojerry,

 I have had both my SP/AV-1s and SP/AV-2s running daily for several weeks now and even I was quite surprised of the changes after 300+ hours.

 I will be doing another production run later this spring with most inquiries now on the SP/AV-2. I will also have the Bella bass modules available soon enough for those looking for a full range setup.

 For anyone still interested in coming May 7th for a small gathering, I will have both available for audition. I would love to hear your thoughts as well.

[Aether Audio]

woodsyi & Friends,

Thanks (once removed) for the comments!  I have to commend Bill on the excellent work he's done in squeezing every last drop of performance from the Bella/SP design.  Clearly he's taken them to another level beyond what I had ever imagined.  

Gee...I'm almost jealous that I didn't do that with them myself...now.   At the time we developed them I was thinking, "I need to build a speaker at a lower cost and that will move in larger volumes (home theater).  One that I don't really care so much (2-channel audio "caring")what it sounds like."

Oh well, I've got a million of 'em (ideas for new products).  I guess I'll just have to build something else that rocks.  Ooops! - too late - already have.  How do they sound?  Hold tight a few more days.  I will say this though:  This time I cared what they sound like.  In light of the above, use your imagination.

-Bob

[Aether Audio]

Deleted duplicate posting...stupid server!

[Bill Baker]

Hey Bob,
  Don't you have your own forum for posting new stuff/ This is my thread, get out.
 Okay, just kidding
 Think you can squeeze a pair of these new speakers to me to audition and demo on May 7th. I'm sure there are many that would be interested in hearing them. Of course, I will set them next to the Continuums. How do you think they will compare.

[ooheadsoo]

At the time we developed them I was thinking, "I need to build a speaker at a lower cost and that will move in larger volumes (home theater). One that I don't really care so much (2-channel audio "caring")what it sounds like."

Oh well, I've got a million of 'em (ideas for new products). I guess I'll just have to build something else that rocks. Ooops! - too late - already have. How do they sound? Hold tight a few more days. I will say this though: This time I cared what they sound like. In light of the above, use your imagination.

Wow, don't I feel great after reading that?

[Jason1]

An explanation for the leanness could be a complete lack of baffle step compensation in the crossover. A speaker with no BSC needs to be placed near a wall.

The woofer is rated at 90db, adding BSC should bring the system down to 84-86 (depending on how much is felt sounds best).

Bill or Bob can feel free to shoot this one down if I'm wrong.

[Aether Audio]

Bill,

Don't you have your own forum for posting new stuff/ This is my thread, get out.

Fine!  I'm outa here.  Just when I was going to ask YOU to be the beta tester too. Just kidding!  We'll talk.


ooheadsoo,

Wow, don't I feel great after reading that?

Don't kid yourself.  This new model retails for 3 times what you paid for the AV-2's.  And the AV-2 is probably 75-80% of their performance.  If you change the crossover parts sometime in the future, you're probably talking 85% then - which is cheap and easy for you to do yourself.  Remember:  High-end audio is all about splitting hairs when you get into these higher levels of performance.  The higher you go, the lower the cost/performance ratio.  Also, the comparison I just made is between different models of our own products, which already have a very high cost/performance ratio.  By the time you're done you'll have a pair of speakers that will easily compare with other systems costing $5K and more.  So...I'd say you can feel real good.


Jason1,

An explanation for the leanness could be a complete lack of baffle step compensation in the crossover.

Baffle step is ALWAYS compensated for in all of our designs.  You don't get a flat response if you don't compensate for it and everything I design is engineered to provide a flat response - period.  I don't go in for "industry curves" etc.  A more likely reason is that room gain is not as strong in woodsyi's room and most folks come to expect the sound you get with it factored in.  A flat speaker usually sounds a little bright to most when they first hear it and it takes a while for the ear/brain to adjust.  Once it does though we've found that most folks don't want to go back to a non-flat speaker.  

Also, if woodsyi's pair has even so much as a 1dB rise in it's response in the tweeter range because of component variations in the crossover, this can be the cause as well.  That's the problem you have when you design a truly flat speaker - it better be perfectly flat above crossover.  Even a 1dB of excess output from the tweeter will have that effect.  If Bill's test gear doesn't have fractional dB resolution, he would likely have never seen it when he tested that pair.  We're talking really splitting hairs here and it's somewhat difficult to see if you don't have several thousand $$$ worth of test gear to verify.  The good news is that its really easy to adjust.  As Bill said, one little resistor will do the trick.  Seeing that the X-O is so low, the resistor value difference would be pretty small so one wants to tread cautiously when making that adjustment.  You'd be amazed at how much difference one VERY small value change can make.

-Bob

[Jason1]

Hi Bob. The Peerless HDS Exclusive 8" woofer is rated at 89.3 db. Either you guys have an extremely custom 96 db version, or you have magic crossovers.    (excuse them lame joke)

BSC by nature lowers the system sensitivity.

[woodsyi]

A more likely reason is that room gain is not as strong in woodsyi's room and most folks come to expect the sound you get with it factored in.

10 Real Traps, 4 GIK panels, 4 8th Nerve corners and acoustic ceiling tiles may be the reason for less then robust room gain.     I will follow up with a report after I install them in the bedroom which has no acoustic treatments.

[Aether Audio]

Jason1,

The Peerless HDS Exclusive 8" woofer is rated at 89.3 db.

Look closely at their published graph.  Even it shows the unit runs closer to 90dB.  There are always variations in production runs of drivers and all the ones we've been getting run almost right at 90dB, sometimes a few tenths more.

Take two 8-ohm speakers and put them in parallel, then pump 1 watt (2.00 Volts) into them.  What do you get?  3dB more output than a single driver of the same model being driven at 1 watt.  Drive them with the same voltage as a single unit (2.83 Volts) and what do you get?  Another 3dB due to increased voltage sensitivity. So...at 1 watt the AV-2's are 93dB and at 2.83 Volts they put out 96dB.  Yes, that's actually sourcing 2 watts in that case but it does reflect the amount of "amplifier voltage before clipping" headroom you'll get.  

In simpler terms, if you set your amp's output to a certain volume level while connected to an AV-1 and then switch the speaker cables over to the AV-2's (without moving the volume control) the AV-2's will play 6dB louder.  Of course this assumes the amp can drive a 4-0hm load without a loss of output voltage, but most modern amps are easily able to do that.  This is why we publish both sensitivity ratings for the AV-2's.  And they are as follows:

93dB @ 1W/1M and 96dB @ 2.83V/1M.

BSC by nature lowers the system sensitivity.

Hmmm...I didn't know that.  I thought baffle step resulted in more output at a frequency band wherein the radiation transitioned from a 4pi to a 2pi field.  That being the case, that range of frequencies are (in a sense) amplified over and above what the output would be without the baffle induced stepped rise in amplitude.  I thought all you had to do then was to attenuate those frequencies, such that the axial output of the system was returned to a flat response with respect to those frequencies that lay in the range below those of the baffle step range.  I kind-of thought of it as "free energy" that once attenuated, actually reduced the excursion requirements of the driver over that band of frequencies.  Sort of like what our waveguides do at the low end of the tweeter's operating range.  To me, all a balffle is, is a poorly designed waveguide with a 180 degree dispersion characteristic.

But what do I know?  I certainly never new that it reduced broadband sensitivity.  Guess I better crack the books a little more.

woodsyi,

10 Real Traps, 4 GIK panels, 4 8th Nerve corners and acoustic ceiling tiles may be the reason for less then robust room gain.

WOW!  You think?  Glad to hear it though.  A man that appreciates the value of room treatment.
-Bob

[Carlman]

There were some comments made from a first-time poster against Bob that I moved here: http://www.audiocircle.com/index.php?topic=27335