Hows the Cabinets coming along? Been checking on your progress. Thanks Rick
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Hows the Cabinets coming along? Been checking on your progress. Thanks Rick
Seems the laquer wasn't quite the correct color. Fortunately only a few portions had been done before we noticed this. So while not back to Square One, definitely back a couple of squares.
Meanwhile the woofers and HF horns are sitting here at my house collecting dust. :(
Major bummer! :( Restorations can be a real @#!&* when you're a perfectionist. ;)
GM
Just reading this fascinating thread.
Has the cabinet finishing finished?
Also what is the bass response like from this cab. Not necessarily with original 803s, but perhaps with a later 416a unit?
Any thoughts?
Sigh. No. As may be obvious, it is a 'as time is available' project on his part. The incorrect stain really set things back, and caused him a lot of extra work. The 803As, 811s, and compression drivers are safely collecting dust with me.
It has lots of really clean bass. But not at 20hz. Despite their external size, I don't think there is as much internal volume as one might initially think - due to recessing the woofers for the horn loading. So I am not sure how effective the bass reflex portion of the tuning is. It would be interesting to model them with modern tools. (Not that I am in any way qualified to do so with any authority. :) )Quote:
Also what is the bass response like from this cab. Not necessarily with original 803s, but perhaps with a later 416a unit?
Any thoughts?
My uncle used to use an equalizer to tweak the bottom octave and probably tame the HF horns mid-range a bit. He also noted that the two cabinets had a little different response from one another. One was a little better in the bass, the other a little better on the high end. Again he used the EQ to correct it. I don't have his old EQ - maybe my cousin has it. So I may be looking for one in the future. Either that or I will just biamp them with miniDSP and let it handle any EQ issues.
I could not tell you what a 416A would do in these cabinets. They have a much lower Fs than the 803As. I suppose once I get my pair of 420A Biflexes fixed up, I could mount them in one of the 820s and measure the bass response. (Some here have recommended just having GPA convert the 420s to 416s, since apparently all but the cone and maybe the spider are the same.)
That's interesting, thanks.
I'd wager not many cabs are flat to 20, or even 40 Hz without a dose of EQ, and in many ways the risk to drivers through over excursion to get down beyond 40-50Hz might not be worth it.
I had a single 420-8B reconed as a 416-8B. The frame/motor are the same.
Finally getting to the end! The '57 cabinet (green components) should be delivered today! Yay!
One detail on the '55 cabinet to be decided:
The wooden horn area behind the grill and flared out from the woofers, is painted black on the 1957 cabinet and is unfinished on the 1955 cabinet. Question of the day is what to do about this:
1.) Leave the area unfinished, as that is how they came originally.
2.) Apply some clear lacquer so that the inner area will still look original, but at least the wood is protected.
3.) Paint the area black to match the '57 cabinet. I am already having the external finish on the cabinet changed to match the '57. So some originality has been lost anyway.
I am leaning strongly towards #3.
Ideas? I have to let him know ASAP.
#3 sounds like a good move.
I'm really surprised that the one cab is unpainted.......... makes me wonder if they were in a time crunch to meet the delivery date, which was a really big deal back then to keep freight costs down as much as practical.
GM
Well, as I have said from the beginning, even though the two cabinets are both called 820Cs and resemble each other externally, they are constructed quite differently. Robert, the fellow who is doing the work, says the later cabinet looks like it was easier to contruct.
On the paint, you really only see it when you shine a flashlight through the grill cloth. He says the '55 box just had a bit of overspray next to the sides. There were also the tips of nails poking through, etc (which he cleaned up). So it was really built kinda messy compared to the '57 box. There are no date or serial # markings. With this in mind, #3 is my choice.
I had to attend a meeting last night, so he is bringing the '57 box by this morning. The '55 box comes tomorrow morning. GM (or anyone): Do you want any particular photographs or measurements before we put the drivers in and close up the boxes?