MicMix MasterRoom XL-305 Spring Reverb Clone

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ethervalve
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Re: MicMix MasterRoom Spring Reverb Project

Post by ethervalve » Sat Feb 13, 2010 5:36 pm

Wow thanks so much for posting that! I find the descriptions in the brochure quite apt.
Very interesting stuff.
Sorry about the delay on sound samples. I caught a nasty bug and I've spent most of the past few days in bed. I'm going have some chicken soup and then maybe I'll brave the trip down to my chilly Montreal basement to record the samples.
In the interim, here are some more more picutures:
http://www.flickr.com/photos/peterjwood ... 428681490/

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mediatechnology
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Re: MicMix MasterRoom Spring Reverb Project

Post by mediatechnology » Sat Feb 20, 2010 8:50 am

ethervalve kindly sent us these samples of snare drum through the Master Room XL-515:

hallreverbsnare5.6.secdecay
http://www.proaudiodesignforum.com/cont ... cdecay.mp3

hallreverbsnare_shortesttolongestdecay
http://www.proaudiodesignforum.com/cont ... tdecay.mp3

plate_3.9decay
http://www.proaudiodesignforum.com/cont ... 9decay.mp3

plateshortesttolongest
http://www.proaudiodesignforum.com/cont ... ongest.mp3

roomreverb_4.9decay
http://www.proaudiodesignforum.com/cont ... 9decay.mp3

rooomreverbshortesttolongestdecay
http://www.proaudiodesignforum.com/cont ... tdecay.mp3

I compressed them to mp3 format to save bandwidth.

Wayne

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haima
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Re: MicMix MasterRoom Spring Reverb Project

Post by haima » Thu Nov 25, 2010 2:44 am

these samples sound really good - i find reverbs like these very useful in a mix... i hope one day to find one of these units - or make something similar!

thanks wayne & ethervalve

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haima
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Re: MicMix MasterRoom Spring Reverb Project

Post by haima » Thu Feb 17, 2011 11:42 pm

Hello Fellas,

Does anyone have the schematic for a "CSR series" MasterRoom?

I have a friend who has one that needs some repairs to the spring drive circuit on one channel...

I haven't seen the unit yet, but he's given me the following info:

CSR Series
Master Room
Model: CSR-23-BL-VU

Its an all gold 2 or 3RU rack case with 3 knobs per channel: Reverb, Decay, Direct. He says there's a mini tape recorder type vu meter in the middle, (possibly an edgewise meter?).

There are multi pin connectors to two external spring columns, one is 3/4 the size of
the other.

He says the circuitry looks to be 100% discrete, rather than opamp based like the later ones.

Wayne or anyone else know anything about this one?

Thanks in advance!
Haima

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mediatechnology
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Re: MicMix MasterRoom Spring Reverb Project

Post by mediatechnology » Fri Feb 18, 2011 6:18 am

The only one I remember having a mechanical VU was the MasterRoom B-series for broadcast. The model number doesn't seem to fit. I'd be intersted in seeing a picture. If there is a problem with the driver or electronics the parts will be numbered. IIRC the driver transistors were Motorola TO-66 devices. On a unit that old check the electrolytics first.

The schematics for the Master Room B-series is here: viewtopic.php?f=12&t=356

The Master Room C Series Manual: http://www.waynekirkwood.com/images/pdf ... Manual.pdf

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haima
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Re: MicMix MasterRoom Spring Reverb Project

Post by haima » Fri Feb 18, 2011 7:26 am

Thanks wayne, I'll post a picture when I get the unit from my friend... might be a little while as i'm about to go on tour. It'll be interesting - hopefully i'll just be able to track down the problem even without a schem.

He says he really likes the one channel that does work - and this guy has two BX20s etc. I can't wait to hear it!

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mediatechnology
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Re: MicMix MasterRoom Spring Reverb Project

Post by mediatechnology » Fri Dec 30, 2011 7:46 am

Just found these sound files of various reverbs including the Masteroom XL-305 and XL-210:

http://old.nabble.com/Spring-Reverb-Dem ... 25697.html

New Years 2012 resolution: I really should get started cutting those springs...

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haima
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Re: MicMix MasterRoom Spring Reverb Project

Post by haima » Tue Sep 18, 2012 1:04 am

Hi Guys and Gals...

I finally found a MicMix Master Room for sale here in Australia. Just paid for it today. Unfortunately it has to be shipped from another state - I'm a little worried about damaging the springs in trasit (my BX20 has some spring/coil issues which seriously effect one side - i'd hate this one to suffer a similar state!).

Any tips on prepping the "reverb columns" for shipping? Other than just loads of bubble wrap...? Do they have a locking/dampening function for travel?

I've attached a few images of the unit - it seems to be a "medium era" unit in the Master Room series? - i'm told it's a:

"MicMix Master Room C Series Spring Reverb System & 2 Sound Columns".

Which consists of:
1 MicMix Master Room CSR-BL-VU Rack Mount 2 Channel Control Unit
1 MicMix C2B Sound Column
1 MicMix C3B Sound Column

Coincidentally it also appears to be the same as the "gold face unit with one vu meter" that my friend owns (that has an issue with the spring drive section on one side - I mentioned a few posts back....)
MicMix Master Room C Series 1.jpg
MicMix Master Room C Series 1.jpg (50.35 KiB) Viewed 17164 times
MicMix Master Room C Series 2.jpg
MicMix Master Room C Series 2.jpg (205.55 KiB) Viewed 17164 times
MicMix Master Room C Series 3.jpg
MicMix Master Room C Series 3.jpg (239.31 KiB) Viewed 17164 times
MicMix Master Room C Series 4.jpg
MicMix Master Room C Series 4.jpg (188.17 KiB) Viewed 17164 times
MicMix Master Room C Series 5.jpg
MicMix Master Room C Series 5.jpg (196.85 KiB) Viewed 17164 times

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mediatechnology
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Re: MicMix MasterRoom Spring Reverb Project

Post by mediatechnology » Tue Sep 18, 2012 10:23 am

Wow! That looks to be one of the earliest C-series. I started there in 1975 and the switchable meter version was before my time.

I'm trying to recall if there was a locking device and I don't think there was.

This may help regarding shipping:

The internal spring assemblies are on an ~1.5" square cross section internal support member.
The reverb springs are around the outside face of this internal member - two each per face.
They are standard Acutronics springs and transducers but longer.
The whole internal gizmo is then hung by springs and internally floating when vertical.
Rubber "feet" attached to standoffs serve as bumpers to prevent the assembly banging into the side of the 4" PVC pipe.

If the spring assembly receives a strong shock while in the vertical position, the signal lines to the transducers would occasionally get cut.
We used 2C shielded phono "tone arm" wire.
It didn't happen often but if it does it can be repaired by cutting the tube open with a band saw.
That wasn't my gig so I never had to do it - the guy that ran the machine shop and production rebuilt them.
I can't recall springs ever being damaged but occasionally wiring would.

Transporting the tubes horizontally is best.

On a unit that old I'd consider recapping it.
If you find that the unit has the molded Mallory vertical electrolytics I would definitely recap it.

Get me a pic of the inside when you get it. Would love to see it.

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haima
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Re: MicMix MasterRoom Spring Reverb Project

Post by haima » Tue Sep 18, 2012 6:17 pm

Great. Thanks for that info on the internal construction - makes me feel a bit more ok about shipping. I'll get the seller to write "fragile" and "ship horizontally" and hope for the best I guess - I know that's no guarantee, but it might help. That and a lot of padding :D

I will definitely post some photos of the insides when I get the unit - and I'll no doubt be adding it to my list of re-cap jobs :lol:

I imagine the schematic would probably match the C series previously posted, but without the EQ - the manual/schematic mentions there are two options. But maybe it's a different design altogether.... we shall see!

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