SDA's with horns?

madmax

Here is a pic of my 1.2's with horn modification.

Actually I'm just testing the functionality of the horns and decided to try them with the bass section of the 1.2's since they were sitting there. These horns are the beginning of my "old school" speaker project. A super high efficiency of over 102db at 1 watt is the key ingredient of the project.

Face

You can get rid of that silly array.

madmax

Here is a side view.

mmadden28

madmax wrote: »

Here is a side view.

Think looks like a tank--Is it iron? Are those welds?

madmax

I think it is cast aluminum and yes, those are welds. I can imagine it mounted on the top of a telephone pole and still be visually stunning.

I was happy to get these in this condition. They look like they were produced and never used. I found some pro 15" bass speakers to try with them. I'm hoping to use a single stage filter on the horn and no filter on the bass speaker so as to not eat up any efficiency. The plan is to use a flea powered amp and still get huge volume.
madmax

ben62670

MM I have to talk to you sometime. You and Mhardy make me think!

skrol

Isn't that the PA speaker from M*A*S*H?

madmax

ben62670 wrote: »

MM I have to talk to you sometime. You and Mhardy make me think!

There is something special about high efficiency speakers. A big part of it is extremely fast transients with big dynamic range. There is the benifit of flea power at the beginning because you can get off cheap. Of course down the road there is more cost because the electronics must get very good to be quiet and well controlled.

Yeah, on the MASH comment that is what I was thinking. Its actually a horn out of an old Altec speaker, the Valencia and very similar to what is in the Altec model 19.

ben62670

All
I have to say is yes sir!
Looking at Fostex 8" full ranges lately:)

ShinAce

madmax wrote: »

There is something special about high efficiency speakers. A big part of it is extremely fast transients with big dynamic range. There is the benifit of flea power at the beginning because you can get off cheap. Of course down the road there is more cost because the electronics must get very good to be quiet and well controlled.

Yeah, on the MASH comment that is what I was thinking. Its actually a horn out of an old Altec speaker, the Valencia and very similar to what is in the Altec model 19.

I was thinking Valencia as well, but a lot of them were black and I'm pretty sure they were iron or steel. My experience was with Valencia 846B's

madmax

ShinAce wrote: »

I was thinking Valencia as well, but a lot of them were black and I'm pretty sure they were iron or steel. My experience was with Valencia 846B's

I'm new to the altecs other than I had a brochure back in the day and finally had to throw it away after drooling all over it.

What I've seen from current sales of these old classics is typically black ones in the model 19's and green ones in the valencias. I've seen different models of the valencias though and one of them even had a different horn so obviously there is a lot more to it that I know. I'll hold a magnet to it and see if its steel. It is certainly cast. Alluminum was just an assumption.
madmax

vc69

Well at least you can warn the neighbors of bad weather.

I have heard many a horn. Altec, EV, Renkus - Heintz, JBL... a bunch. I have never thought they were good for hi-fi playback. Particularly at close range. They are designed to throw sound over long distances. Even K-Horns and LaScalas need some breathing room and are definitely punchy. Maybe you will enjoy that.

I understand and admire your quest. And I will follow this thread with interest. I don't think you will be pleased with the results.

/.02

ShinAce

Here's a pic of 846B's:
http://springfield.craigslist.org/ele/1411753887.html

madmax

ShinAce wrote: »

Here's a pic of 846B's:
http://springfield.craigslist.org/ele/1411753887.html

I should have probably just bought a pair like that to start with. Yes, that is the original design I want to follow.

VC69, I hear your comments. I have a fairly big room to use them in, maybe 20 x 30'. And, I've heard of people who hated their sound until they heard the right amplification with them (assuming mine turn out to have the Altec sound). Its really no big deal because if they don't work out then I end up with a pair of loud raw efficient PA speakers (that I paid too much for) for my musical instrument room.

madmax

On Friday I received one of the Eminence Delta Pro 15A bass/mid speaker. I only ordered one because I wanted to make sure the curves sound as I think they will. They did. I have not built a box for it yet but to give it a try I sat it on the floor upside down over the heating register. This allowed me to get rid of the opposing sound waves from the back of the speaker. Not the best test bed but it gave me a good idea what it sounds like. I crossed the horn over with a first order filter at 1200 hz.

So, how does this contraption sound? Bass is reasonable but rolls off pretty quickly, maybe 70 to 80 hz. A sub should blend nicely. The highs are pretty well controlled but sound different than the tweeters I'm used to. Its quite nice. What really shines is vocals and sharp drum rim hits. When I picked up on how nice the vocals were I pulled out all my CD's with people (really) singing. Male and female voices both sounded real which is usually an achievement given you always have to cross over somewhere between the lowest male and highest female voice. Given the combination of the woofer response and tweeter filter they seem to work out well. One male voice (forget the artist) was a little hollow so I'll play around a little more. All in all I think I've got the right driver to match my tweeter horns. This could have gone very badly.
madmax

Edit: Oh yeah, I got the efficiency I was looking for too. The 15" is quite loud with only a few watts. I still had to turn down the horns though. They must be something like 105db at one watt without attenuation although I have no spec. The woofer is almost 102db and I'm giving the tweeter about half the power I give the woofer. Maybe two or four woofers would make a difference?

Face

Depending on how you wire up, an additional woofer can add 3-6db.

megasat16

MadMax,

I want to ask a few things with regards to super efficient speakers. I like the idea of super efficient speakers myself. But when the speakers reach 100db and above sensitivity, I think there are some disadvantages of such speakers.

Speaking generally, there are crazy harmonics in most recordings and there are other instruments adding noise to the recordings and even some of the CDP, amps and preamps are adding low level noise in the reproduced audio signal. Even with modest CDP, Preamps and a good amps, these noises can be reproduced to a certain level but the low sensitivity speakers automatically masked them so it's desirable.

With super high efficiency speakers, some of these noises may be more audible. I like to learn how you cope with these noises if you may.

madmax

megasat16 wrote: »

MadMax,

With super high efficiency speakers, some of these noises may be more audible. I like to learn how you cope with these noises if you may.

This is correct, they do amplify everything to a higher level. Excess power is burned up in heat and adds little. The things to worry about are hiss, hum and a general non-clean signal from any component.

I have been lucky. The phono, CD and preamp are absolutely dead quiet. The preamp with the big 300B tubes make all sorts of cool sounds as they heat up but become very quiet. The amps are way over powered (100wpc) and should be lower power (maybe 5wpc). In general the higher the power of the amp the more noise it makes in the first few watts. My particular amps happened to be good enough but you can still hear a small amount of hiss, somewhat the same as a standard eff speaker with the typical mid line amp. I'm not too surpised about the quietness of the Manley gear because I know EveAnna Manley uses very high eff speakers and likes to use her own equipment to power them. With the Avantgarde horns there is no horny type sound and no odd sounds or characteristics but they are expensive. The ones I'm putting together now will most likely have their own character (because of the chosen drivers) but should have the dynamics of the AG. Of course they only cost 1/15th of the AG.

I like different speakers and equipment because of different characteristics with different music. If I had the best equipment ever made I would still be putting together systems to see what they do and where they accel.

I found a pair of 12" drivers I would have used because the curves are absolutely perfect and match the horn but there is something about the larger the driver the lower you can cut off the horn frequency while still keeping the sound even when offcentered from the sweet spot. Using the 15" will give it a bit of personality at the crossover point which I could have avoided with the 12". You give up something to get something else.

madmax

megasat16

Madmax,

Thanks for sharing your personal experiences! I wonder if you can get rid of a preamp and amp all together and use a passive buffer (like NP's B1) with small Triode tube amps?

But the thing is that the noise floor for most Tube equipments are in the 80-90db range where SS can be over 100db easily. Have you tried some really nice SS amps and see how they sounds with your Tube Preamp? There are Pure Class A amps with 25-50watts to try and see if they can quiet the horns a bit more and adds better dynamic to the music. And it'll have the power to push the woofers harder if need to be.

megasat16

These horns should help smooth out your lower bass regions.

madmax

No sand shall enter my horn shack.
madmax

adutCloulfida

I have a cherished amp with a captive cable. I want to replace the cable but would like a bit of advice. How should I connect the new power cable to the amp. I mean, the electrical connection.

Any advice greatly appreciated.

tronyui

Life is too short to be serious, laugh it up.

edbert

And reported...oh, HA HA HA HA!

zingo

adutCloulfida wrote: »

I have a cherished amp with a captive cable. I want to replace the cable but would like a bit of advice. How should I connect the new power cable to the amp. I mean, the electrical connection.

Besides this being a thread jack...

Replace the captive cable with one of these and solder in the old leads. It will require a bit of chassis modification, but allows you to use whatever power cable best suits you.