Thursday, February 1, 2018

Altec 32A, 32C, Emilar EH1210, EH800, EH500 and Faital Pro STH100




This is a cumulative report on horns I listened to and tested from May 2016 until the end of 2017. All the tests were done through the mono hifi rig using the above Altec 802 compression driver fitted with a GPA 34852 diaphragm + an Altec 414A in a repurposed Altec 861 cabinet running in full-range mode tied together by a 6dB/octave high pass crossover/EQ hinged at 2500 Hz. 

Altec 32A and 32C


Altec 32A (top)
Altec 32C (bottom)

 The Altec 32A (metal) and 32C (plastic with ribs) horns are lineal descendants of the Western Electric 32A horn as found in the WE753 speaker system. I've had the plastic 32C since '09 and lived with the metal 32A for over a year and can say that these are the most sophisticated native 1" horns I've heard and owned to date.

Altec 32A


Altec 32A

Altec 32A + 802 + 414A

Altec 32C


Altec 32C

Altec 32C + 802 + 414A


Metal or plastic? 


It's ironic that the later plastic 32C sounds more vintage than the earlier metal 32A. Definitely, the longer throat of the earlier 32A and the type of material used for construction influence the sound. But in what capacity, I cannot surely define. The iPhone RTA results reinforce the cooler and more modern sound I hear from the metal 32A versus the warmer and sweeter plastic 32C.

The magnitude of difference is not great. Similar to the 20275 vs. 34852 Altec 1" aluminum diaphragms - distinct enough not to be used as a stereo pair but still excellent performers in their own right. However, those who are expecting a front-row presentation may find both these horns too laid back.

Watch out for roughly finished throat edges in the 32A which are detrimental to performance. So far all the plastic 32Cs I've seen have very smooth throats.

Emilar 


As soon as I landed in the US in May 2016, I tried to collect the Emilar horns talked up by Joe Roberts in his war against the devil's trumpets before they became unaffordable. 😉

EH1210


Emilar EH1210

Emilar EH1210 + 802 + 414A

This wasn't recommended by J-Rob but it was cheap enough to try. The EH1210 has the most extended high frequency response according to the iPhone RTA but subjectively it was the least refined sounding horn in this group. I think one can do much better with some modern offerings, see the last entry below. 

Emilar "Bowtie" EH800 and EH500


Emilar EH500 (left) + Emilar "Bowtie" EH800 (right)

WARNING: these two Emilar horns are heavy cast jobs, doing the audiophile knuckle test can result in serious injury! 😃

EH800


Emilar "Bowtie" EH800 

EH800 + 802 + 414A

If you are looking for a modern sounding horn with a more forward presentation but without the shout and distortion of the Altec 811, then this is the horn for you. Exciting sound but guaranteed not to make your ears bleed. 

I think the low end cut-off at 800 Hz spec is a bit optimistic. For maximum satisfaction start around 1200 Hz and work upwards.

EH500


EH500

EH500 + 802 + 414A

This is a native 2" horn with a finely machined 1" - 2" throat adaptor. Once again I find the 500 Hz cut-off an overestimation for a horn of this size. I'd start crossing around 900 Hz and up. 

My ears do not agree with the iPhone RTA. I found this horn to be mellower than the EH800 "Bowtie." The tonal balance of the EH500 is somewhere in between the Altec 32A/B/C and the EH800.

EH500 in Large Format Mode


EH500 sans adaptor + Renkus-Heinz SSD3301

With the JEL N1600 XO in tow, I removed the 1"-2" throat adapter and bolted the 2" exit Renkus-Heinz SSD3301 directly to the horn to sample large format tones. I got juicy mids and smooth highs from this combo.

Late addition:


Faital Pro STH100


Faital Pro STH100

I wanted to sample what can be had off the shelf at Parts Express for under $100 and ordered a pair of these small aluminum tractrix horns by Faital Pro.

STH100 + 802 + 414A*

*RTA was done at a later date in another location,
hence the difference in low frequency response 

With the Altec 414A running full range and the STH100/802 combo crossed at approximately 2500 Hz, I got very clean (if a bit dry) high frequency harmonic augmentation with no nastiness at all. To my ears, this tractrix horn is preferable to the EH1210.

CODA


For the past 4 years, I've been blogging about horns and compression drivers. Justifiably, the horn/driver combo seasons the speaker system's sonic flavor. However, these components only cover the upper three octaves of the audio band (mostly harmonic overtones). I would be remiss if I didn't stress the greater importance of the Altec 12" 414 woofer/midrange because it is tasked to reproduce most, if not all, of the fundamental notes in music from 30 Hz to 4000 Hz. That's seven octaves, practically the frequency range of a piano.  

I've been trying, but so far haven't found alternative 15" or 12" woofers that play the midrange as well as the Altec 414. The good news is, Bill Hanuschak of Great Plains Audio told me last year that they still re-cone 414s and their product page lists an Alnico 414-8B(16B)

14 comments:

  1. The reason the metal 32s have rough throats is that they were made from the original 32 molds, which have a smaller (about 5/8") throat to match the WE drivers they were originally designed for. The throats are drilled to 1" to match the 1" Altec drivers, and the drilling is often not quite centered. That's why the 32Bs are shorter, they're actually designed to match a 1" throat driver... I've got a pair of plastic 32Bs without the external throat supports the ones in your pics have, I wonder if there's a sonic difference?

    Roscoe

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    Replies
    1. Always a pleasure to hear your insights, Roscoe! I didn't know the WE713's had smaller throat diameter, I always presumed they were 1" drivers. I had a chance to buy a single plastic 32 w/o the ribs but hesitated. An hour or so when I decided to BIN, it was gone. :(

      JE

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  2. Recently at another local audiofool's we tried the JBL 2441s with 2440 diaphragms on both the EH820s and the EH500s with good results. The JBLs are mine, and I have a pair of 820s if you want to give them a listen as well...

    Roscoe

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  3. I just discovered this blog recently. I've been inspired by your projects, and I'm planning on emulating some. I just bought a pair of 32b horns, and I'm on the look out for the drivers (I'm on the fence between finding old, or buying new from GPA). I also plan on making an open baffle similar to yours for my pair of Lorenz S888.

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  4. I am fully enjoying your blog and this test of horns was especially eye (ear) opening.
    Two questions:
    1) Could you describe your measurement process? Source of pink noise, microphone distance from drivers/horns etc.
    2) You discuss altering the crossover points for different horns. Could you describe the methods you use to accomplish that?
    Thanks for a great blog!

    ReplyDelete
    Replies
    1. 1. Octave RTA $5 app by Onix, iPhone ~ 1m from the speaker, how I use it - http://jelabs.blogspot.com/2017/03/altec-small-format-diaphragms-aluminum.html
      2. I only used one crossover hinged @ 2500 Hz in this blog entry. The only exception was when I bolted a 2" driver directly on the EH500 and linked the XO there. I suggested starting XO points in the text to give readers an idea of the physical size.

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  5. Hello,

    Sorry to comment on an older post - but I've been entertaining the idea of a 414A and horn combo for some time now. Are the Renkus-Heinz SSD3301's a good place to start with compression drivers, or would you recommend waiting for something in the Altec 802 range to come along?

    Thanks

    ReplyDelete
    Replies
    1. The Altec 414A has a great midrange and all it needs is a little bit of help in the top three octaves. In your particular application you are better off using a 1" compression driver like the 802 with an original aluminum diaphragm (or GPA equivalent). If your budget cannot stretch that far consider the Emilar EA/EC175 or Renkus-Heinz SSD1800/1400.

      I only included the SSD3301 large (2") format driver in this article to show that the Emilar EH500 also works well as a 2" horn

      JE

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    2. Just thought to look back to this!

      I was able to pick up some Emilar EH-800s with the 16 ohm EC-175s for a song. Next is cabinets for my 414s (repaired 601s) and a crossover. I'll share the result of the work at some point and credit you appropriately.

      Thanks for your help.

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    3. JE: Were you ever able to compare the RCF H3709 straight-throated hornshto the Altec 32a/32b?

      I've got a pair of the RCFs and do enjoy them with my Altec 9844 (dual 414z) cabs.

      I'm curious to know if it's worth seeking out a pair of 32b (or 32a) horns, or if my RCFs get me close enough to the 32a/b sound not to bother.

      Once I get my 604-8gs in right-sized cabinets, I'm going to go the JE Labs single 414z / 802-16g route using the pair of 614 cabs my 604s are currently squeezed into.

      Thank you for the great insights you've shared over the year or two I've been following your work - indispensable.

      Cheers,

      JB

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    4. The RCF showed a lot of promise. To my ears, it was definitely better than the 811 but not quite as refined as the Altec 32Cs. I wish I had more time to listen and compare but I was already preparing to move back to the USA.

      If you have access to Altec 811/511s and their sonic character don't bother you, then perhaps it isn't worth pursuing the "bent horns".

      Thanks for the kind words!


      JE

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