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100db speakers - like your A7 VOTTs?! You can't be serious.

124.168.214.175

Timbo in Oz

In Reply to: RE: Initial Report, Film Cap 180 degree orientation - Employing new-style Clip Leads posted by drlowmu on August 18, 2016 at 08:24:26

The only kind of speaker I'd be bothered to use - for hearing small changes at this level of 'experimenting' - is one with close to perfect impulse response. Sensitivity isn't an issue or a help here. Not at all.
Speed and waveform integrity does, which are orthogonal with timing. Minimally (distantly) miked music with as few mikes in coincident / other 'stereo' arrays, would also be essential.
After all, science has taught us that we get most information about music - the affective information, with an a Geoff, like you tell us you care about, from the starting transient of all acoustic instrument's notes.
Timbre, expression / intent, timing and interplay.
VOTT A7s were good speakers in their day, but yours still have most of their flaws. Poor FR, poor / inconsistent directivity, and early onset overload of the main driver, due to excursion problems.
{;-)!!!!!!!!
Confirmation bias, run riot.

Warmest

Tim Bailey

Skeptical Measurer & Audio Scrounger

Edits: 08/19/16 08/19/16

Follow Ups:

RE: 100db speakers - like your A7 VOTTs?! You can't be serious. - PakProtector 17:59:24 08/23/16 (6)
Thanks Tim for putting the A7 stuff into words. I tried them, along with the later JBL and the transition from bass reflex to horn loading drove me nuts. For some stuff it was pretty good, but on many others, better results lie elsewhere...LOL
cheers,
Douglas

Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
- I would certainly not expect to hear nuances and small changes. - Timbo in Oz 22:08:36 08/23/16 (5)
  For me speakers with good impulse response, and
  
  i) first or third order crossovers on the tweeter,
  
  ii) no Low-Pass xover (or a 1st) on the main driver - because it rolls off cleanly.
  
  iii) a reasonable match for dispersion to both sides of the crossover point, smoothly narrowing higher up is all we can hope for.
  
  iv) Good overload behaviour, low distortion, and slowly declining FR are also important. Flat within that which is going to be difficult with SET amps, to boot.
  
  v) smooth diffraction behaviour from the enclosure / baffle.
  
  vi) a quiet enclosure. (Geoff has sort of done that, with all those ceramic/concrete blocks).
  
  Are all important to truly hearing what is going on.
  
  I do not believe high sensitivity or high efficiency is vital, but it's not a bad thing.
  
  Once you own such a system - in enclosures with smooth diffraction behaviour - the next step is 'stats. Which is where I am going.
  
  LBNLeast - I've been in this hobby for over 40 years now and have heard quite a few A7 VOTT systems, and I wouldn't own a pair as a gift. I'd sell them.
  
  Warmest
  
  Tim Bailey
  
  Skeptical Measurer & Audio Scrounger
  - RE: I would certainly not expect to hear nuances and small changes. - PakProtector 13:45:11 08/24/16 (4)
    While not the 'end all' a stacked pair of Quad 57's is nothing to sneeze at. Not quite willing to make the investment, but I did enough development work on amps for such to know what it takes to get the most out of 'em...:)
    
    For the time being, I'll stick with horns, active cross overs and gobs of power so most of the time I can *REALLY* stay away from clipping...not just thinking I am...LOL
    cheers,
    Douglas
    
    Friend, I would not hurt thee for the world...but thou art standing where I am about to shoot.
    - The 63s will run off two modified LEAK Stereo 20s, strapped and high-pass filtered at 150Hz - Timbo in Oz 14:50:19 08/24/16 (3)
      40 watt mono-blocks, 4 ohm taps for both OPTs, giving a 'strapped OPT tap' of 2 ohms.
      To retain the QUAD's impulse response the filters are high quality first order Passive Line Level inputs crossovers inside the amps.
      I don't think the LEAKs will be working very hard.
      I do not expect that system to clip. That's for the colder months.
      And in Summer they will be driven by a nice big rebuilt Perreaux 6000C, again with passive 150Hz 1st High-Pass input filters.
      Bass? 4 or 5 distributed DIY subs driven by a total of about 600 watts LP @ 150 Hz 3rd order, and analogue Eq'd - for now - by 2 to 4 1/3rd octave equalisers to get down to 20Hz if possible. ? Two big stereo power amps and two integrated amps.
      Again, I don't expect much clipping, even though I do like to listen loud. :-)!
      I'm not big into Rock music and not big into Mahler, I'm mostly into HIP classical.
      I listen to live acoustical music about once a week, mostly choral with organ, and some chamber and chamber orchestra.
      I used to record concerts for later broadcast on FM, and intend to go back to it.
      As I'm a pensioner this has all taken time, a bit of money each month.
      But we are now close to the first install, with an interim bass array of two boxes and 4 spherical encl. Giving 2 9" and 4 8" bass drivers - all getting down to 35Hz. That will keep us going and get my wife happy.
      Yet to finish? two clam-shell P-P sealed subs (boxes are built), then build two TL subs with KEF B139s. I already have a large RB sub with a dedicated locally mfd long-throw 10inch ELF driver.
      
      Warmest
      
      Tim Bailey
      
      Skeptical Measurer & Audio Scrounger
      
      Edits: 08/24/16
      - KEF B139s in TL cabinets - Lew 11:10:00 08/27/16 (0)
        
        In Reply to: RE: The 63s will run off two modified LEAK Stereo 20s, strapped and high-pass filtered at 150Hz posted by Timbo in Oz on August 24, 2016 at 14:50:19
        
        Tim, that's what I use as woofers to go with my Beveridge 2SW speakers, which cross over at 100Hz. I use a Dahlquist crossover just to provide the low pass filter, and I drive the TLs with a vintage Theshold Stasis 50W amplifier. I built my TL cabinets 40 years ago as the basis for a 3-way system, sold them after several years and then bought them back from the guy who owned them, after many more years. They are about 4.5 feet high, 20 inches deep, made of 1.25-inch MDF and veneered in formica, modeled on the Bailey formula published in Wireless World. I had them stored in my basement ever since repossessing them, until 3-4 years ago, when the Beveridge speakers came into my life. There were many moments over the years before I bought the Bevs when I contemplated trashing the cabinets and selling the NOS KEF woofers that I had kept around for the sole purpose of using them in the TLs. I am so glad I did not do that. The TLs mate very seamlessly with the Beveridge sound. They will be a perfect mate for your Quads, too.
      - Tim, The system will only be as good as the modded Leak Amps - drlowmu 00:29:46 08/25/16 (1)
        
        In Reply to: RE: The 63s will run off two modified LEAK Stereo 20s, strapped and high-pass filtered at 150Hz posted by Timbo in Oz on August 24, 2016 at 14:50:19
        
        On the Leak schematic, R21, 100 Ohms of series resistance, in the B+ filter to the Finals, needs to be avoided at ALL costs.
        
        Suggest you PSUD2 a " Flywheel " B+ filter, as per THIS Forum, maybe eight years ago. ( L1/C1/L2/C2 ) Ls are 1 and = < 20 Ohms DCR. Easiest author to read on Flywheel supplies is Forum Member John L. Hasquin, and a good second choice is John Swenson, both are EEs and better yet - smart in audio.
        
        You system will only be as good as your amps !!
        
        That is where SETs can shine, IF done right, most are not, for sure Simplicity rules in audio design. You are listening to an extra ( 3rd ) stage, a phase inversion, and two coupling caps in series, that any good SET amp easily avoids.
        
        Have FUN !
        
        Jeff Medwin
        
        Go away Geoff. - Timbo in Oz 03:19:38 08/25/16 (0)
        
        In Reply to: RE: Tim, The system will only be as good as the modded Leak Amps posted by drlowmu on August 25, 2016 at 00:29:46
        
        My amps are fine.
        
        Warmest
        
        Tim Bailey
        
        Skeptical Measurer & Audio Scrounger
RE: 100db speakers - like your A7 VOTTs?! You can't be serious. - drlowmu 15:32:29 08/21/16 (0)
Tim,

I would like to very respectfully say that you are not hearing what I have in my living room, and that additionally, and more importantly, you are dead wrong.

I thought almost ALL the moist - experienced listeners knew that ALTEC, JBL, and ALE, horn loaded, are the minimum possible to use - as speakers, if you do tube design.

If you ever get to the USA, come on over and visit me, give a listen !!

Thanks.

Jeff

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