Allen Gyro Speaker dimensions

[musikfan]

Someone please redirect me to the thread that may contain the information which I am seeking. Otherwise, please respond here if you can help.

I am going to be acquiring an Allen 300 with two gyro cabinets. From the picture, they appear to be about as tall as the organ, but I am trying to find out what the depth would be (the seller has not been able to get that info to me as of yet). I need to be able to fit them through my doorway and I'm just a tad concerned as my doorways are much narrower due to my house being so old. I have 29" clearance. I've been given different dimensions by different people. I'm sure each one is right, but it would be good to know specifically. I realize there were multiple models out there which were each different.

Thanks all....

[jbird604]

Looking on the Allen tech site, it appears that all drawings of the old gyro boxes have been taken down. (GRRRR....) I believe these boxes were right at two feet deep though.

MOS-1 models with gyros would've had a split setup for each channel, and the gyros would have only run at a single speed, which was a very slow one. The purpose being not to introduce tremulant or celeste, but to overcome the sterility of the tone, making it seem less like it was coming straight out of a single speaker. Over the years, many of these got replaced with stationary speakers, such as HC-12 cabinets, as the motors and belts would wear out and get noisy, contacts got staticky, etc. But then you may find that they are just fine, and if so, and if you have room for them, they do add a nice movement to the sound.

As to the split setup, each channel would've had one type 100 gyro, which is about 33" square and, best I recall, about 24" deep. Each channel would also have a bass box that might or might not be attached directly to the gyro box. The bass box would be about 33" x 18" on the front and also about 24" deep.

So you may find that you are getting four separate boxes, two gyros and two bass cabinets. If one of the bass boxes has two 15" speakers in it, it is intended for the Flute channel, which carries all the pedal stops as well.

I know this doesn't fully answer your questions, but it's all I could find out from here. Good luck!

[musikfan]

John,

Thanks for your reply. This information was helpful and I'm sure that if I'm only dealing with a two foot deep cabinet, it will easily clear my doorway. The cabs are quite large, but they will be nice for the sound quality they provide. I like the motion of the gyros as it gives some "movement" to the sound, especially for how dead the room is where I keep my organs. I'm hoping to eventually put a reverb on the console for added sound quality. I'm also going to probably use my 2 HC-12's that I already have.

Thanks again...

[AllenAnalog]

I just measured the Gyro cabinet on my 423-C MOS-1 organ. It is 33" high by 33" wide by 18.5" deep. Hope that helps.

Adding:

Since the 423 is a theater organ, the gyro spins at a fast speed when on. There is a tab to direct some of the sound to the gyro cabinet (but some voices remain connected to the internal speakers) and a tilting tablet to turn the motor on and off. It has two separate audio channels going to the speakers, with 4 slip rings on the shaft. Each channel wiring has a series capacitor and inductor mounted on the inside of the cabinet. I cannot find a model number sticker inside the box. The motor nameplate is on the bottom so I can't see the rpm rating.

Obviously the theater models were wired differently from the church models.

These cabinets are easy to service since there are so few components. A new capacitor on the motor, a new belt, cleaning the slip rings and replacing the series capacitors in the audio feed is about all you would ever need to do if there are problems. Mine still works fine with no work done to it.

[jbird604]

I remembered today that I still had a bass cabinet sitting around that had been the lower part of a gyro. I measured it and it was indeed 24" deep. Since Larry's is only 18.5" deep, whatever you are looking at is probably like his or like mine, certainly no deeper than 24". And measuring the frame of the old gyro I could tell that it was also 33" x 33" on the front, same as Larry's.

[musikfan]

I remembered today that I still had a bass cabinet sitting around that had been the lower part of a gyro. I measured it and it was indeed 24" deep. Since Larry's is only 18.5" deep, whatever you are looking at is probably like his or like mine, certainly no deeper than 24". And measuring the frame of the old gyro I could tell that it was also 33" x 33" on the front, same as Larry's.

John,

That's great info to hear. Thanks for the extra information. Definitely no worries about getting it through my doorway now!