I agree with your point regarding irreversible modifications. Currently getting the mags re-charged and a new crossover. Luckily, the are not irreversible...Originally Posted by EliFisk
I love my Valencias - really fun to listen to. Right after I picked them up someone said to remember keep in mind that they are non-renewable vintage speakers and that irreversible modifications are a bad idea.
Sometimes it makes life easier if you simply accept that the Valencia is NOT a perfect loudspeaker.
My advice is to enjoy the Valencias for what they are, and what they do well. Take notes on their shortcomings as well as their strong points.
Then, maybe consider a scratch build based on the knowledge and experience you gain from the Valencias.
I built a pair of Onken 360 liter cabinets, added Emilar horns with Werner Jagusch XOs and have been happy with them.
I agree with your point regarding irreversible modifications. Currently getting the mags re-charged and a new crossover. Luckily, the are not irreversible...
Yeah, these prosound components were designed for either acoustically very large or very small cabs with everything in between a 'size Vs bass' trade-off. Consider that point source [cone] drivers were designed based on a ratio of net cab volume [Vb] where the driver's resonant frequency [Fs] is raised 1.56x in a sealed alignment. This of course will be a different number for every driver since its compliance [Vas] is hard to keep constant in a production run, so one chooses an average and of course if a DIYer measures their drivers, then they can get it spot on, though in the scheme of things the manufacturer's specs will suffice if they are known to be 'close enough' [+/- ~10%] accurate.
The 846B's 416 has a published compliance [Vas] = 26.47 ft^3/749.5469 L, so a theoretically optimum cab = 26.47/1.44 = 18.382 ft^3/520.52 L net and if any added series resistance [amp output impedance, XO components, speaker wiring] increases its effective [Qts' = Qts + Rs] up high enough, then this will make it larger with [Vb] = [Vas] normally being the upper limit as is tuning these large cab alignments to driver [Fs]:
Altec Thiele-Small Parameters
mh-audio.nl - Home
Altec later was forced by the changing times of speaker design towards ones based on T/S filter design theory that ignores added series resistance, etc., unless the designer knows to account for it, hence the smaller recommendations in later pubs, GPA, etc., and the fact that these will usually be near/at a wall or corner, allowing smaller cabs, though still huge by today's standards where [very] high power capability allows [very] inefficient drivers, ergo small cabs tuned based more on its Qts or Qts' than its Fs, compliance.
A popular fairly quick, reversible way to hear a more small cinema/nightclub, etc., type of performance:
High Efficiency Speaker Asylum
GM
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
I have been enjoying the speakers, but I seem to be hearing some distortion from one of the drivers. 806-8A. They have been tested at Great Plains and the diaphragms are said to be perfect.
Is there an easy way for me to check the alignment of the diaphragm in the housing?
Sounds like it may be rubbing...
Easy way? Well, you would have to remove the diaphragm and look for rubbing, but everything is such a tight, precise fit that if it's rubbing it's because it's blown. FWIW, I periodically damaged my late, lamented, ultralite diaphragms by tearing the VC's seam to the domes till finally they burned up in an amp meltdown. I doubt this would happen with the weaker 806s unless really overdriven, but it at least would be visible as a hairline crack/separation where it 'disappears' under the black plastic ring without having to remove it.
GM
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
Do you still have the original diaphragms? Might be time to get a new pair from GPA. 90 bucks each. I would recommend not getting any of the Chinese phragms on ebay. They sound like crap
these are the original diaphragms. Bill at GP serviced the drivers last month and said they looked good.
Its odd that you are hearing distortion. Thats usually from too low a xover, overdriving the diaphragm, clipping the amp, bad xover components... Anything I am missing?
And check ALL your connections from the source to your speakers. Also swap individual components in and out. Sounds like something is messed up.
BillWojo
Yeah, if the drivers are good, there's lots of places in the signal chain to add distortion plus acoustics can play tricks on us, so could even be a woofer VC.........
GM
Loud is Beautiful if it's Clean! As always though, the usual disclaimers apply to this post's contents.
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