Rectilinear III Highboy Project

Sounds about right. Old walnut veneer can really soak up the juice. I'm generally at 5 to 6 applications before things are looking right. On teak or oak veneer, I can get that in maybe 2, no more than 3 applications.

Biggles
 
Again, my comments reflect examples from the Mini-III model, but I think this all translates to the larger Rect. III as well. Pics show examples of at least two of the dark grille cloths used by Rectilinear, and also some product literature that shows this was later revised to off white.


View attachment 1110073 View attachment 1110074 View attachment 1110076

As far as the Highboys go, from what I can tell they used the off-white first, then went to the brown stuff.
 
As far as the Highboys go, from what I can tell they used the off-white first, then went to the brown stuff.

That matches with what I personally know about my Highboys. They are an early pair, with the single tweeter level control that were manufactured between September and December of 1967. They were 100% stock and unmodified when I purchased them from the original owner. The date code on the Philips midrange (alnico magnet) was 67-38, which means the midrange was made the 38th week of 1967 (September 18 - 24) and the original owner purchased them in December of 1967.

The original off-white (oatmeal color) grills were still nailed in place and had never been removed prior to me purchasing them.
 
A Rectilinear adv back in late 60s or early 70s stated that the grill cloth with its slight resistance was designed in to even out the treble dispersion. Makes some sense to me.
If you are wiping off as much as you're applying, after accounting for solvent evaporation, then you are well done applying oil. Furniture stores told me that boiled linseed and turpentine mix 50:50 or so. Well ventilated too.
 
And here I am considering Howard's Restore-A-Finish and Feed and Wax. You guys make me look pretty lazy (which I don't need any help with).
 
Question for you finish guys; my Highboys have their original finish intact. They feel a bit dry and there are a few minor imperfections. To me, they look much lighter than other pairs I've seen. When I bought them the seller told me they were teak, but all of the literature I have seen described the veneer as walnut. So, perhaps they are walnut and have experienced some UV fading over the 51 years of their existence. Honestly, I like them the way they are, but want to freshen up the finish (there are a few small blems here and there). Here's what they look like now:

Whos_Next.jpg


What approach and what finish would you recommend? I want to keep this look and not apply anything that will make them darker. My original plan was to sand them down to the veneer and then apply a few coats of natural Danish oil, but I've also considered the JBL standard recipe of 75% boiled linseed oil + 25% turpentine. The drawback there is I will have to wait a few months for some better weather. I moved into a townhouse in December and only have an unheated 1-car garage to work in. I have applied Danish oil indoors in the past, but with the BLO + turp, I'd want to be able to work outdoors, or at least in the garage with the overhead door open.

I'll look them over closely tonight to see if they actually require much sanding. If not, is it possible to just freshen up the original finish by applying a new coat or two of Danish oil?
 
High Boy Rec's are really nice sounding platforms when restored.
If I recall correctly I think Parts Express had those same tweeters! or I see them once in a while on the action sites.
DC
 
Question for you finish guys; my Highboys have their original finish intact. They feel a bit dry and there are a few minor imperfections. To me, they look much lighter than other pairs I've seen. When I bought them the seller told me they were teak, but all of the literature I have seen described the veneer as walnut. So, perhaps they are walnut and have experienced some UV fading over the 51 years of their existence. Honestly, I like them the way they are, but want to freshen up the finish (there are a few small blems here and there). Here's what they look like now:

Whos_Next.jpg


What approach and what finish would you recommend? I want to keep this look and not apply anything that will make them darker. My original plan was to sand them down to the veneer and then apply a few coats of natural Danish oil, but I've also considered the JBL standard recipe of 75% boiled linseed oil + 25% turpentine. The drawback there is I will have to wait a few months for some better weather. I moved into a townhouse in December and only have an unheated 1-car garage to work in. I have applied Danish oil indoors in the past, but with the BLO + turp, I'd want to be able to work outdoors, or at least in the garage with the overhead door open.

I'll look them over closely tonight to see if they actually require much sanding. If not, is it possible to just freshen up the original finish by applying a new coat or two of Danish oil?

I'd say the reason the speakers are light is because they've been very well preserved and protected. Probably as close to original as one could ask. Typically, wood and wood finishes darken with age and exposure (I have a flame mahogany Empire dresser that's almost black... didn't start life like that 185 years ago). And most UV damage I've seen is very inconsistent and uneven. One speaker would be darker than the other, or one side on a speaker would be darker/lighter than the others. I've never tried to refresh an existing oil finish, (most my projects have been all or nothing affairs), but I've heard that when a Danish oil finish get a little dry, all you need to do is do a wipe down with some more to refresh. And they look like walnut to me.
 
I'd say the reason the speakers are light is because they've been very well preserved and protected. Probably as close to original as one could ask. Typically, wood and wood finishes darken with age and exposure (I have a flame mahogany Empire dresser that's almost black... didn't start life like that 185 years ago). And most UV damage I've seen is very inconsistent and uneven. One speaker would be darker than the other, or one side on a speaker would be darker/lighter than the others. I've never tried to refresh an existing oil finish, (most my projects have been all or nothing affairs), but I've heard that when a Danish oil finish get a little dry, all you need to do is do a wipe down with some more to refresh. And they look like walnut to me.

Thanks for the reply. I think a fresh coat or two of Danish oil may do the trick. I remember some uneven spots on the top of one, not from UV, but from water, and that's why I was thinking I may have to do some sanding. Not the black plant rings that are common and a pain to deal with, just a little uneveness. It may just be in the finish and not penetrated to the veneer. I have them under some sheets right now, I'll look them over more closely tonight and get a better assessment of the condition. They aren't perfect, but were very well cared for by the original owner.

Yeah, this is a more common example of uneven UV fading (tan lines):

4301_B_3.jpg


Those will have to wait until summer when I can sand them down and apply several coats of the original JBL 75% BLO + 25% turpentine finish.
 
MCM Fan said:

Yeah, this is a more common example of uneven UV fading (tan lines):

4301_B_3.jpg


And a very common example of the need to refoam that woofer!
 
Hey,

Here's a few shots of my early III's. They're considerably lighter than their later counterparts. Look like just a different flavor of walnut.

RectilinearII053.jpg


RectilinearII051.jpg


Biggles
 
MCM Fan said:

Yeah, this is a more common example of uneven UV fading (tan lines):

4301_B_3.jpg


And a very common example of the need to refoam that woofer!

Done:

JBL_4301_B_5.jpg


They were an even better example of of some crossovers that needed recapped.

Before:

JBL_4301_B_4.jpg


JBL_4301_B_2.jpg


After:

JBL_4301_B_Crossover_After.jpg
 
Goodness! And from JBL! Shame!

Really, I wonder if that's what my L15 crossovers look like since the speakers sound like crap these days.

BTW, Beautiful work. Bravo.
 
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Goodness! And from JBL! Shame!

Hard to blame JBL on this one. More like innocent victims of 20 years of improper storage. At least the previous owner had stored them flat on their backs. So, no sagging spiders. Just a recap and refoam and they are sounding great. I knew they needed refoamed (pretty obvious), but the melted wax stalactites on the caps came as a surprise (I was planning on recapping them anyway, so not a big deal). Just waiting for warmer weaher to refinish the cabinets.
 
Yay! Found a Peerless MT20 tweeter, so my parts collecting is complete (with the exception of some grill badges).
 
It's all looking good, and it appears you've selected Mundorf E for mid and Dayton poly for tweeter - - very sensible choices. Did you ever measure the caps from the other cabinet?...... and what values did you end up using here?
 
It's all looking good, and it appears you've selected Mundorf E for mid and Dayton poly for tweeter - - very sensible choices. Did you ever measure the caps from the other cabinet?...... and what values did you end up using here?

I used a 100uF with a .1 bypass, and replaced the others with the same values. I did measure the caps and resistors after removing them for reference...

Mystery cap... 87.5 & 91.2uF
2uF cap... 2.27 & 2.19uF
10 ohm... both 10.3 ohms
2 ohm... both 2.1 ohms
 
Thx for reply. As expected, the resistor values are pretty true to original. I don't think we ever saw pics of original crossovers, but sometimes these Rectilinears used 5-watt resistors and it's not a bad idea to increase the wattage rating. Re: cap measurements, it's very interesting to see these measurements so close to the 2.2uF and 90uF that I mentioned in post #24 for the Mini-III's. Oh.... and now I see the bypass cap straddling the large Mundorf.

Keep it up and report back on results. Also, maybe show the type of pot control in your speaker - - will this require any attention?
 
Installing drivers. Always wondered about Rectilinear's aversion to using mechanical fasteners. At least these used RTV on the mids instead of the liquid nails stuff like on my Model XII's.

20180301_180839.jpg
 
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