First post - Interested in 878B Santiagos

[xinu]

So are the original diaphragms intact or not? I use the 21597 phragms in my 802D's and really like them.

Everything excluding the 411 cones is original.

I haven't pulled the horns out yet to inspect the diaphragms. That is next on the to do list.

[bowtie427ss]

No expert here, i just have a green thumb. Altec green.

Oh, and i stay at one of those motels now and then.

That said, i would opine that the OP's ears are trained to speaker systems with more VHF extension than a 2-way Altec.

As somebody posted on another forum "God lives in the midrange", and this philosophy seems to have rang true with the Altec engineers all the way back to the beginning.

Certainly the crossovers need re-capping, replacing the chokes is optional and not immediately necessary, though i would tend to lean toward good air cores.

A lot of folks are really liking PIO caps in their Altecs. I really don't have a recommendation, i find Dayton 5% polys to work just fine in 90% of applications, and have really grown to not like Solens on horns at all, they're tizzy, almost sibilant.

There are a lot of mechanical connections in the HF circuit, and the 30904 essentially doubles the count, not to mention the ~24 feet of wire it adds to the circuit. These are all points where the tiniest amount of corrosion adds series resistance. Can you see where i'm going with this?

Like so many things in life, the littlest things are most easily overlooked. It's the little things that can add up to a big difference/improvement.

[xinu]

Thanks for the welcome and direction GDM!

1) The L-pads seem to be functioning OK. No noise during rotation and attenuation is working.

2) Very strident HF when the dial is on 0 and way down in level at 10. 4 on the dial sounded best to me. I'll continue to play with the L-pad and see if that helps.

3) The 30904 is in circuit.

4) The caps are original. I would like to build a new x-over to the N801 spec and recap the equalizer and Zobel. I'll leave the original alone.

First I'll pull out horns and inspect the 806s.

Greg

- - - Updated - - -

No expert here, i just have a green thumb. Altec green.

Oh, and i stay at one of those motels now and then.

That said, i would opine that the OP's ears are trained to speaker systems with more VHF extension than a 2-way Altec.

As somebody posted on another forum "God lives in the midrange", and this philosophy seems to have rang true with the Altec engineers all the way back to the beginning.

Certainly the crossovers need re-capping, replacing the chokes is optional and not immediately necessary, though i would tend to lean toward good air cores.

A lot of folks are really liking PIO caps in their Altecs. I really don't have a recommendation, i find Dayton 5% polys to work just fine in 90% of applications, and have really grown to not like Solens on horns at all, they're tizzy, almost sibilant.

There are a lot of mechanical connections in the HF circuit, and the 30904 essentially doubles the count, not to mention the ~24 feet of wire it adds to the circuit. These are all points where the tiniest amount of corrosion adds series resistance. Can you see where i'm going with this?

Like so many things in life, the littlest things are most easily overlooked. It's the little things that can add up to a big difference/improvement.

The wife tells me I have a brown thumb

My ears may have been trained to VHF but due to atrophy in that range I'll look forward to enjoying where 'God lives'.

Wow, I checked out the prices on 18uF PIO caps. I think 90% fine polys will suit my budget better.

Yes, I see were you're going and thats all part of the fun.

Thanks,

Greg

[Elitopus1]

I used Jantzen 18uf caps in my 801/809 crossovers (they are 809 with binding posts instead of 1/4" jacks). Those caps sound pretty good. I have used Daytons in other projects and those sound good too.

Also I use the PIO motor run caps. There is a guy on ebay who has 18uf motor run for 8 bucks each. They are the Genteq brand. I just built my 604G crossovers using this brand and they sound great.

Just another option

Genteq Dielektrol Capacitor 18uf 400VAC 50 60Hz 97F6658RC | eBay

[xinu]

I used Jantzen 18uf caps in my 801/809 crossovers (they are 809 with binding posts instead of 1/4" jacks). Those caps sound pretty good. I have used Daytons in other projects and those sound good too.

Also I use the PIO motor run caps. There is a guy on ebay who has 18uf motor run for 8 bucks each. They are the Genteq brand. I just built my 604G crossovers using this brand and they sound great.

Just another option

Genteq Dielektrol Capacitor 18uf 400VAC 50 60Hz 97F6658RC | eBay

I'll check those out.
Curious if you replaced the L-pads when rebuilt your x-overs. If so what type/brand did you use?

Thanks,

Greg

Unfortunately the ebay Genteq seller doesn't ship to Canada eh.

[Elitopus1]

When I rebuilt my 801/809 xovers I ditched the L-pad for fixed resistors. Same for the recent Markwart 604G xovers. You can find what the resistance is on the L-pad setting you like and then just use a resistor of that size. Otherwise I am sure there are some good quality L-pads out there.

It sucks that seller wont ship to Canda. He is a nice guy and gave me a little discount on combined shipping and buying all the caps I did. Do you have a friend just over the border who can get them for you?

Otherwise there are some good poly options out there. I just found the PiO to be a little smoother on the horns. If you are coming from some brighter speakers you might prefer the poly caps anyways.

Bowtie: Are these speakers similar to your 9846? Same woofer but different horn drivers?

[xinu]

Today's task was to remove the horns and clean the throats.

Wouldn't you know it, one of the fasteners on the upper right of the horn was cross threaded into the T-nut and was pushed away from the horn-board to make it impossible to unscrew from the front. The back of the cab is not removable and it's too tight to get up in there near the top through the woofer hole and clamp onto T-nut in an attempt to unscrew to fastener. I'll try to get a hack saw blade behind the bolt head and I hope after a few hundred short strokes it'll be off.

That fibreglass stuffing around the horn is turning into dust and has to go. I'll have to find some suitable replacement foam.

[RonSSS]

Now I remember those speakers.
I always have to go look at pictures. :-)

Don't see those too often. Good that you found the B version as it has the better 411 woofer.
Good luck getting the horn out.

When you get the diaphragms out you can just use a shop vac on the throat to suck junk out of the screen.
The screen is pretty stout.
I prefer the sound without screens, but some abhor this mod........

Maybe the smart guys can chime in, but I wonder if these would sound good with M19 crossovers?

I bought a pair of 9846-8A a number of years ago and got totally screwed on them. Woofs were dead, wrong HF drivers, mismatched X-overs etc etc.
I have everything to put them back together, but never did so. A future project perhaps.

Have fun and welcome!

Ron

[xinu]

Thanks for the welcome Ron.

I did manage to hack off the fastener to remove and clean the horn with a bottle brush. I think removing the 806 screens is a good idea at this point. After all these years the screens may not be as acoustically transparent as they once were and I don't think the CD produces enough air pressure to blow any dust out

The 9846-8A looks like an interesting speaker, Barcelona parts in a pro cab?