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(Re)building a Hi-Fi Room


ca. 2006

Eight years ago I vacated this space, not knowing that I would be back someday...

Late Spring 2016

Altec 861 cabinet

Among those that didn't make it into the 20 foot container in 2008 was a pair of Altec 861 cabinets loaded with generic 15" drivers. I used one temporarily to get some sounds going in the room while I figured out how to repurpose the other cabinet.

Amplification


Grommes LJ2

 This sweet "Little Jewel" PP6V6 integrated mono amp fired up with no problems after almost 8 years of silence.

Rek O Kut B12GH + Velvet Touch

My hand-carried Velvet Touch tonearm "blu-tacked" on a ROK B12GH and mounted on a state-of-the-art crate plinth. 


After a thorough cleaning and re-lubrication of the main bearing, Papst motor and replacement of motor mounts, the dreaded motor vibration is still felt on the tonearm finger lift. I have to send the idler wheel to Terry Witt for a rebuild and plan on building a heavy plinth.


Unlike the fussy Rek O Kut, this Pioneer PL6U is running quietly on its original lightweight plinth after I replaced the 3 perished rubber motor mounts with rubber grommets + light cleaning and re-lubrication. It sounds great with a $40 Stanton 500 cartridge!  

Pioneer PL6U

Line-level sources


KLH Model Twenty One

Classic Hi-Fi FM table radio found in a bicycle shop. 

Western Electric 111C
+
UTC A20

Stereo > Mono transformer mixer for the iPod Nano

Hi Eff Speaker



Since the Altec 861 share a similar internal volume with the Altec 614, I went to Lowe's to get 3/4" plywood cut to the size of the front panel. Using a Harbor Freight Router + Jasper Jig 200, I cut a hole for a rear mounted Altec 414A and a rectangular 2" x 7" port to mimic an Altec 614.

Altec 2-way

Altec 861 loaded with an Altec 414A running full range augmented on top by an Emilar EH800 horn or Altec 32A horn with an Emilar EA175-16 compression driver.


Work in progress...

Comments

  1. Hi Joseph,
    Welcome back!
    Are you using both the 111c and the a20 together? How are they wired?
    Regards,
    Pete Boser

    ReplyDelete
    Replies
    1. Hi Pete,

      Great to hear from you! Yes I'm in town.

      Re; WE111C + A20, not quite together...was comparing the sound of the two transformers, but got distracted by the lack of SE/DHT amplification ;)

      Hope to see you at CAF next week!


      Delete
  2. How do you like the EH800 compared to the 32A?

    Roscoe

    ReplyDelete
    Replies
    1. Hey Roscoe!

      Both are good just different in presentation. The design of the Emilar "bowtie" EH800 seem to be an attempt by Jonas Renkus to fix everything that was wrong with the Altec 811 and I believe it was an unequivocal success. No more nasty coloration/distortion since the throat opens up immediately to a nice flare and the horn is made from thick and heavy cast aluminum . It sounds more forward and extended than the ancient 32A which even some Altec aficionados claim lose high frequencies due to the bent throat design. They are probably right and their claim, measurable.

      But I think aside from a compact cabinet there was also another reason why WE engineers did the 90 degree bend in the horns found in the WE753 and WE757A studio monitors, which is to make it easier for them to blend with a good sounding direct radiator low frequency driver. I've heard the WE753A, WE753C and a WE757A in the past and they all sound very coherent with an almost seamless transition from the woofer to horn/driver combo.

      With regards to achieving this coherence with my Altec 414A, I think the 32A still has a slight edge over the EH800, although I can live with it if I didn't have access to a 32A or 32B.

      Just my 2 centavos...see you one of these days, man ;)

      JE

      Delete
    2. Are your observations based on the same driver on both horns, or is that an all Emilar vs all Altec comparison? I've got a pair of 802-8Gs, but no Emilar drivers....

      Roscoe

      Roscoe

      Delete
    3. Yup, my observations are based on using the following drivers on both the Altec 32A and EH800: a recently acquired Altec 802-8D with GPA 34852 16 ohm diaphragm, Emilar EA175-16 and EC175-8.

      Delete
  3. Joseph,
    I'm a long time fan. Curious if you have had any issues with input impedance matching from your we111c to the preamp. I burned some resistors on my Dynaco Pass 2 that should only have seen line level current. I may have hooked up to the low impedance input on the pre. Look forward to your future posts. Jason

    ReplyDelete
  4. Hi Jason,

    I've only used line level transformers with digital - CD/DVD player and streaming from a Laptop/iPad/iPhone. So far no problems at 1-2V output.

    JE

    ReplyDelete

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