Old rubbish I've collected, useful?

[moody]

Went round to my mothers place over the weekend, picked up a whole bunch of junk that has just been lying around useless. I'm wondering if a couple of the items may have any real world use, or if there worthwhile selling.

 

Firstly, 6 old Goodmans Audium 15" speakers, huge old magnets, all good and I assume originally intended for PA usage, but not useful in this day and age - but would hi-fi people want them?

 

Secondly, and more in line with this forum, 2 old Altec lansing drivers, 291-16k, but at some stage made into 8ohm. Are these heavy old things any use? I have a couple of small horns that would fit them (but not nearly as big as the drivers) but I don't know what they are intended for and how they compare with current equipment. Would they be sought after if I tried to sell them? Is it worth putting them on the horns and boxing them up as hi boxes - maybe with a smaller tweeter for the very high end?

[WynnD]

The Altecs might be worth something. You'll need model numbers. (I'm using Altec horns for the high end of my three way system.) They're rated around 35 watts and mated to the correct horns provide a lot of sound for very little push.

[agedhorse]

The 15" drivers are worth pretty much what somebody will pay for them.

 

The Altec 291's are interesting for a couple of reasons. While JBL focused on 2" exit and struggled with high frequency response (think 2480 driver), Altec recognized the limitations of the 2" format and settled on 1.4" exit which, along with other features, gave almost an octave better high frequency response. Take this with a little grain of salt as there were different diaphram materials being used at that time and while JBL used phenolic-linen, Altec also offered aluminum in their larger format driver. You need to know what diaphrams are in those drivers, and note that only the Altec 1.4" exit horns or other 1.4 or 1.5" exit horns that may require a drill template made to drill new mounting holes on the horn flange to match up with the driver. They do not work well at all with a 1" exit style horn.

 

With modern DSP crossover eq, those drivers can be made to sound quite acceptable with good horns. Note the relatively low power handling (

 

IF you can find a good pair of 1.4 or 1.5" exit horns, they could be something you could use in a DIY PA cabinet provided you were willing to engineer and construct it well and biamp it with appropriate hardware.

[J.]

You could also make a killing by putting them on eBay and using the word "vintage" in the auction title. I sold one of those really crappy old chrome body Shure mics for $40 that way.

[moody]

Well, the couple of horns I have I'm pretty certain are smaller than 1.4", but I'll look out for something of the right size.

 

Given the power handling, would something like a hi-fi amp be a better power source than a normal 200 watt plus PA amp? I have a yamaha amp sitting here that is 50 watts per side. I also have dual 3 way crossovers, so I should be able to put something decent together presuming I find a horn to fit (otherwise I'll try to sell them).

 

How good is the lower end response? Would they function reasonably well with a JBL K140 in an appropriate bin as mid-range?

[agedhorse]

Crossed over at say 800-1200Hz, the horn drivers on a suitable horn (loads down to 800Hz) would be good for a speaker system of about 600 watts, the K140 would be just fine but note that it's really a 200 watt driver.

 

This system will work quite well with a 24dB/oct slope and between 800 and 1200 Hz, active with some HF shelving boost starting about 5k at 6dB/octave and you will have a decent sounding 2 way box. Don't bother with passive xovers.

[moody]

 

This system will work quite well with a 24dB/oct slope and between 800 and 1200 Hz, active with some HF shelving boost starting about 5k at 6dB/octave and you will have a decent sounding 2 way box. Don't bother with passive xovers.

 

 

I'll have to have a look at my crossovers (warfdale). I'm not sure exactly what you are saying with an HF shelving boost and I'm not sure if my crossover can do it. It all depends on finding the horns first of course.

 

I have other drivers aside from the JBL's that I can use with more power handling, I just know that the JBLs are good quality and being well known are probably the easiest to work with.

 

This is all for long term type stuff, my current (small) system is still good for what I'm doing at the moment - I'm just looking ahead to what I can use when the little yamaha 12" mains aren't enough.

[agedhorse]

The HF boost would be available on something like the Driverack PA.

[moody]

ok, looking at what is available... horns are both difficult to find and expensive. I'm seeing several options: get a 2" horn and an adaptor (adaptors are also ridiculously expensive and lengthen the potential horn longer than I would like), Keep looking until I find a horn (may take a while), or take a bit of an experimental initiative.

 

Could I make a narrow wooden plate to go between the driver and a 2" horn with a widening flare to 2" carved into it. Making the wood Narrow enough to still allow the threads from the driver to fit to the horn.

 

More ambitious and possibly the most disasterous: Hand build / carve the horns. Is this even possible? Are there any standard, flat rather than curved, horn geometries that could be used?

[agedhorse]

The flare rate between the adapter is important, that's why they are deeper than you wish.

 

This is the real issue when adapting drivers. YOu don't want to adapt to a 1" exit either because that would be a real problem. Either find a 1.4 or 1.5" horn. You might search on horn flairs or HF horns etc. and see if something comes up. There are some economical options in the US, but don't know about AU.

[irvingklaws]

I had the same drivers and used some small MCM horns with them. It was some years ago, and while MCM lists a horn that looks the same (note the 3-bolt mounting pattern) the listing does not specify the throat diameter. The horns I had looked exactly the same and were in-fact 1.4" diameters:

 

http://www.mcmelectronics.com/product/54-330

 

Not sure how viable and option it is for you to order and have them shipped. Be sure to verify the specs first if you decide to go that route...the price is right.

 

I never really got around to using them in a project...no time. Just sold them a few weeks ago in fact. $150 on Craigslist, and they were gone in a day.

[agedhorse]

Withoutt he dimensions, I would expect the low frequency cutoff to be around 1000-1200Hz, so it's useable but with a higher xover point than I recommended previously. It's odd that they don't list the throat diameter.

[irvingklaws]

Yes, it is odd although it's the same horn in the picture. I did see that the picture has a caption "only for reference". They also don't seem to list the MCM driver the horn is supposedly for. I bought mine around 8 or 9 years ago.

 

I recall getting them because someone on Audio Asylum had reported building a 3-way using these with (as best I can recall) an Eminence 12" cast-frame woofer and unnamed tweeter, in a 1 cubic foot sealed enclosure with a custom (of course) crossover. Sounded like a good idea, but never actually got to try it.

[wiresix]

if its old enough altec stuff is worth good money. I just unloaded some "vintage" POS (top of the line in their day) speakers on ebay for $1300. I thought they sounded horrible, but anything with a VOTT tie is worth bank!

[PJenkins]

Hmm...interesting. I have a A/L 291-16 Driver and horn in my shop right now. The horn is 32" wide X 12" tall and about 24" deep ,BIG HORN. The customer bought 2 of them and quickly killed this one. I sourced a replacement diaphragm from Great Plains Audio. It's actually a sub diaph. with a wiring kit. Agedhorse, I'm betting he will need a new diaph. on the other horn in short order. If you do have them in stock we may be doing business soon.

 

Regards,

PJ

[agedhorse]

I have 2 left.

[moody]

I'm still trying to figure out whether I should get these working or just try to sell them. I'm quite happy with my current setup but I've only done little gigs with it.

 

Can someone give me an idea of what this driver with a good horn would be the equivelent of on todays market. Unfortunately, both time and money are valuable to me at the moment and I want to see if this would be even close to worthwhile doing.

[agedhorse]

A little more solid sounding than a JBL 2425 (which is a modern 1") not as smooth in the high end, when installed on an appropriate horn.

 

They may be worth just selling, there is a new-found fondness for "vintage" Altec.

[moody]

Revisiting.

 

I've just had a look at a couple of old cast horns that I have. Unbelievably they are 1.4" exit and match up to the drivers.

 

The question is, they are little horns and the drivers dwarf them, all the horns I have heard about are massive - will they match up well to the drivers and what crossover frequency would they like? All the info I can give is pictures:

 

[agedhorse]

1200-1500Hz minimum.

[moody]

 

1200-1500Hz minimum.

 

 

Thanks, and as I expected. At least they are usable now though.

[moody]

Last question (promise).

 

Would a smaller than optimal sized horn reduce the efficiency of these drivers? I know that the frequency response is compromised but will the volume within the frequencies that it can do still be approximately the same?

[moody]

Hmmm... that post just vanished.

 

Yes I know that the horns are very efficient and I probably won't have to turn them up much. I'm thinking in a box with 2 12s - still stand mountable but high enough to just sit on subs if they are on the edge of a stage.

[moody]

(the missing post was I'd have to pad them down with any mid driver anyway)...