Doc modding Marantz imperial 7

[karatestu]

This just gets better and better Turns out this table was made for pub's in the 1930's. A "boozing" table made by Gaskell & Chambers. How fitting that they are boozing tables and I do like a drink Looks like they are antique's now selling for £120 - £160 in good condition. I better be kind to them. Made out of solid oak apparently The legs are called matchstick legs. The little plaque on mine says Gaskell & Chambers Makers Leeds The information I found says they were based in Birmingham

Quote "Made by Gaskell & Chambers Ltd, of Dalex Works, Coleshill St, Birmingham, who were once Britain's biggest bar fitters and manufacturers of beer engines, hand pumps and pub cellar equipment. They were also known for Great Art Deco interior designs, for cocktail bars, smoke rooms, theatre bars, and assembly rooms, and a wide selection of furniture including tables, armchairs, settees, stools, and hat, coat, and umbrella stands, in oak or mahogany.

The red table top is in good vintage condition and the four well shaped legs are all in first rate order and made using good quality oak. The table possess the Gaskell and Chambers Badge. All firm and ready to go."

https://www.billyhunt.co.uk/store/p141/ ... ham.html

https://www.taylorsclassics.com/coll ... ino-top/

https://www.taylorsclassics.com/asset ... MF0.jpg






Can't believe these have been stuck in the corner of a shed for so long. I remember them being used in the 80's for village barbeques that were held on our farm

[karatestu]

More observations from listening.

Playing Weather Report Domino theory.

The track swamp cabbage - there are two notes played by Joe Zawinul (RIP)on the keyboards close together every few bars on the intro to this track. I have never heard them tail off for so long in to the distance of the sound stage. Truly amazing.

The title track - Domino Theory. There is a wood block played every few bars. I have never heard it so vibrant with it's decay so rich and woody.

[karatestu]

After removing the tongue and groove top from this "boozing table" and clamping all the joints back up I am left with this.







l

[Fretless]

Looking good Stu.

[antonio66]

^^^^^^^
Going back to the tables, what a find, really like the way the legs splay out slightly, good for stability, and I would have thought for your speakers with a downward facing driver: If your speakers will stand on the top, minus the table top of course, you're onto a winner

If only. The tables are 70 cm tall with the table top removed. If I put my speakers on top of that they will be too tall - tweeters will be over a metre off the floor.

The plan is to build the speakers "into" the table so the top baffle of the enclosure will be where the table top was and the tweeter pod will go on top of that. The bottom baffle will be within the four legs just below where the cross braces are . The sides will need panels made to fit inside and joined into the splayed matchstick legs. Hope that makes sense.

The splayed legs make things harder as the panels to fit between the legs will have irregular angles rather than easy 90 degree ones. And there are mortise and tenon joints to do. Hope i can pull it off - need to buy some more tools.

[karatestu]

The tables tops are made of tongue and groove oak boards. There are enough of them to fill in the spaces on the sides of the table down to the depth I need (just past the leg cross braces). It would be a shame to waste them because they are exactly the right thickness (20mm) and the same thickness as the pieces that are already in.



I would need to continue the mortise and tenon joints to the bottom of the enclosure and join the two oak boards together that run horizontally and will make up each side. Biscuit joints or maybe a tongue and groove type thing ?

But they are slightly warped Apparently there is a method to straighten out warped boards involving wet towels and a hot iron . Might give that a go. Oak boards are really expensive especially if they are quarter sawn like these. I assume they are quarter sawn as the grain runs in uniform straight lines.

That would leave only the top and bottom baffles to find. I could make them using two boards of 1"x 7" quarter sawn oak and make sure they are well joined together as there will be a hole cut in the top for the mid bass. Not sure that will work unless I line the underneath of the two panels with steel or aluminum plate.

The leg cross brace will have to go unless I can modify it - it will be in the way of the down firing mid bass if left as is. I could attach the bottom baffle to this cross brace and remove just the bit that gets in the way of the driver. Something to ponder on there.

The top baffle will be easy. The infilling required for the sides a bit harder due to angles and mortise and tenon joints. The join between the bottom baffle and the sides will be the hardest though. I measured the angle that the legs splay out and it is only 5 degrees I thought it was more . Anyway at least I know the angle and how to adjust the cuts on the side panels to account for it.

25 mm baffles should be heavy duty enough don't yer think ? I plan to put a round over on all their four edges - probably a 25 mm one, the same as the thickness of the baffle. The corners may be a problem to round over but I will think about that.

I am going to end up with an internal volume of about 24 litres which may or may not be too much. If it is too much then I will have to go to town on the bracing and steel lining until it is ideal.

It's good to have something already a third built to use and it's going to save me a fortune in wood.

[karatestu]

Did a bit of sanding to see what was underneath that dark stain. The classic Oak colour appears from underneath I am not a fan of wood that is too dark.



Also sanded one of the table top boards. It needs more work but there is some matching oak wood under there If I can get the slight warp out then these will be used to fill the sides in down to the depth I need.



Found some other wooden boards that I think might be Oak as well. I might be able to get together enough to do the whole lot.

[karatestu]

Well, you all knew it would happen didn't you. A week or two ago I mentioned that there was one combination I hadn't tried and that was a down firing 6.5" mid bass with a 5.25" up firing mid bass.

Well I have done it and listening to it now Let's see how this combo fares



All I had to do was cut down a couple of baffles that were used on my 40cm wide enclosure made out of decking boards.

[Ordinaryman]

Surprise, Surprise

[karatestu]

It had to try it otherwise I would have always been wondering and not being able to sleep at night

Well I'm so glad I did For this particular box volume and listening room it is superior to both the bipole 5" & 6.5". Having the 5.25" up firing means I can get the driver almost at the centre of the baffle. The down firing 6.5" will need to go back as well so the magnets line up for joining mechanically (even better force cancellation).

Something I am noticing about displacement and rooms as I play about with different sized drivers is that there is an optimum. With these kevlar drivers they definitely have a house sound which just gets bigger as you increase diameter. For best results with my kit, room, ears and taste the 6.5"& 5.25" combination is perfect.

The baffle step correction and lower cabinet vibrations are still happening and all the things I said recently about the 6.5" bipole and foam dice shaped tweeter pod still applies. This combo just seems to drive the room perfectly, everything is in perfect proportion and is still exciting and involving.

I have 220 cm2 of displacement now which just so happens to be the same as the 8" in this range of drivers but with the advantage of baffle step correction and lower cabinet vibrations due to force cancellation.