Recent content by bowtie427ss

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    Help with the Value

    Design Acoustics D-4 will likely yield more results. About 200 bucks each circa 1974.
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    Mounting 288c on mr954a mantaray

    Here's a couple pics borrowed from the net that show how they welded and flush ground the studs.
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    Mounting 288c on mr954a mantaray

    You MUST remove the studs from the driver. The pockets in the mounting face of the horn are only deep enough to accept the head of a bolt, NOT a stud and nut. It's 14 degrees F here this morning, when it warms up a bit, i'll dig thru storage and post a pic of the factory setup where the plate...
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    Bridge QRC 1200 with unbalanced cable ok?

    Assuming you mean QSC amplifiers, those models have no business going below 8 ohms when bridged, you'll let the magic smoke out. Most versions of 802 have an impedance curve that dips to ~3 ohms across a portion of the bass range. Very few amplifiers will be happy with that load in bridged mode.
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    Question about Altec Cabinet Design

    I guess i dropped the ball on the "B" part of your question. The answer in a word is compression. Many of the same benefits and attributes that are characteristic of high frequency compression drivers are also true across at least a portion of the BW of a suitable low frequency transducer...
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    Question about Altec Cabinet Design

    In Altec circles it's called a constrained throat. JBL fanboys will call it a Perkins spec in honor of Cal Perkins, the designer of the 4550 and 4560. https://fohonline.com/featured/in-memoriam-cal-perkins-1942-2022/
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    Altec 9471 A amplifier

    Comes from a series of very heavy duty, low noise gear. See page 10 here: https://www.preservationsound.com/wp-content/uploads/2011/02/AltecFullLine1968.pdf
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    Altec A7 crossover recomendations

    902 has a response that's shifted an octave upward from the 800 series drivers it replaced. Don't cross it below 1200hz. The model N-1201 network would be an excellent choice giving you precisely a circa 1980 A7X load.
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    12” BK speakers with altec woofer

    Altec part number 034633 was the woofer used in model 8 series II, model 14, 9842 monitor, and the LF-2 subwoofer. 033785 was the woofer used in model 9 II, model 15 II, and Santana II.
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    Altec VOTT bookshelf speaker build

    Once upon a time, Electori, a Japanese importer was receiving a supply of salesman model VOTTs that were loaded with 405's, no HF element. Whether they were actually made by Altec or not remains a mystery. https://www.audioheritage.org/vbulletin/showthread.php?10185-mini-Altec-Voice-of-the-Theater
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    12” BK speakers with altec woofer

    The woofer is a Rola, made the 37th week of 1976.
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    I found this cool RCA box. What was it for?

    Totally agree. The metal lightning bolt logo came on gear. RCA would have applied it front AND CENTER. An accessory box would have used a water slide or decal.
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    Aquired pair of Bose 901 series1. Home made or real?

    They look like an FE-103 variant.
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    Aquired pair of Bose 901 series1. Home made or real?

    Series I and II, and model 800 industrial used 8 ohm, cloth surround drivers made by CTS, wired 3 x 3 series/parallel. Same 8 ohm drivers were used in several small pro monitors back in the day, CGM, Bullfrog, Galaxy Hot spot, etc..
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    Aquired pair of Bose 901 series1. Home made or real?

    https://www.scaruffi.com/svhistory/arun4.html
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