Leslie 103 speaker - Need to connect to Wurlitzer 4500

[mamooshka]

I need to connect a 103 Leslie to a Wurlitzer 4500 that is connected to 2 Leslie 147's. I don't have a connection kit for the 103. Does someone out there have one with a cable? If not, does that mean I'm SOL? Also, given that it can be done, I'm definitely going to need the details on how to do it. I know technicians with a lot of years of experience with Wurliters and Leslies, but this is an unusual combination that I want. I have heard this combination before a long time ago and it is awesome as i remember it. I have had the 103 for a long time but have never gotten around to it. We don't live forever so i think its time while i still have it in me to play. Is Jimmywilliams out there somewhere? From what i've seen on this site he'd be the man.

[jimmywilliams]

Hi. THe 103 was a Gulbransen-specific Leslie that was later adapted for some other organ models. I am not familiar with how your Wurlitzer model splits the channels. If you can tap off the string/reed/complex channel, and it does NOT include the bass channels, then you can attach that channel to the 103. The 103 is only made to carry the complex channels and does NOT carry the fulte/tibia voices or the bass pedals. There were kits out there that could connect a 147 and 103 (I am not sure what make of organs these were designed for??) where the 147 would carry the flute and bass and the 103 would carry the complex channel.

If you want to take a stab at it yourself, belkow I copied/pasted the info from a document I created about Gulbransen Leslie speakers. You will need two switches and a 12v DC power supply. The info I have below describes how it was connected to a Gulbransen Rialto K. For the Wurlitzer complex voices you would also leave pin 5 unused (or try tying it to pin 4 but I am not sure how the phase shifting will work then - it may cancel out the channel on one side of the 103 altogether). Remember the Gulbransen Rialto K had two mutually exclusive complex channels divided by groups of pitches and as far as I am aware Gulbransen was the only line to do this. 12vDC for switching voltage will suffice - even down as low as 10.5vDC will work. I hope this helps.

- jim

Model 103

Used in pair with the 102 for the Gulbransen Model K (factory model 1135) Organ only. It was also used with some models of Lowrey theater organs. This cabinet is not designed to be used by itself, only in pair with the 102. A converter hookup needed to be installed in the 1135 Model K organ to allow use of the Model 103 in pair with the 102 – usually this adapter was factory-installed in the organ.

103 9-Pin Cable
1 Black Signal Ground
2 Red (not used)
3 Yellow (not used)
4 Orange Main C Channel (Amplifier 2)
5 Green Main C# Channel (Amplifier 3)
6 White Lower Drum Control – voltage to transistor-switched relay circuit (tibia tremulant) +13vDC
7 Violet Middle Drum Control – voltage to transistor-switched relay circuit (multi-rank celeste) +13vDC
8 Gray AC Power
9 Blue AC Power

[mamooshka]

Jimmy, thanks for getting back to me on this. Your info gives me some idea what i'm up against. Doesn't sound like a slam dunk at all, but then again I sort of knew that. I'm not a techy so I wanted to run a few more things by you to get a better understanding.... I found schematics on the internet for the 102 and 103 and they both evidentally use the same exact 4 channel amplifier (please verify for me that is you understanding as well), but the two leslies have a different space generator and speaker setup. Is that true? If so, are you saying in your first reply below that 2 of the 4 channels in the amplifier in the 103 aren't used at all? I'm a little confused by
2 Red (not used)
3 Yellow (not used)
4 Orange Main C Channel (Amplifier 2)
5 Green Main C# Channel (Amplifier 3)

Does pin 4 Orange correlate to channel 2 in the amplifier? Is that what you mean by (Amplifier 2)?
Does pin 5 Green correlate to channel 3 in the amplifier? Is that what you mean by (Amplifier 3)?

I'm not familiar with Main C Channel vs. Main C# Channel. What is that exactly?

Also, in the Wurlizter, i'm pretty sure the upper and lower keyboards each are on there own seperate channel, and the pedals are on the same channel as one of the keyboards (I forget if its the upper keyboard or lower keyboard). But i'm not aware of any channel splitting regarding strings/reeds vs. flutes/tibias. If there isn't any channel splitting regarding strings/reeds vs. flutes/tibias where does that leave me with the 103, and where would it leave me with the possible use of a 102 if i had one or wanted to get one. I know of a technician who said he had connected 102s to a Wurlitzer 4500 and i remember it sounding great, but the person who owned and played it said it would be playing wonderfully and then suddenly the whole sound would go through a mysterious sudden downgrade. Any ideas on that?

[jimmywilliams]

I found schematics on the internet for the 102 and 103 and they both evidentally use the same exact 4 channel amplifier (please verify for me that is you understanding as well), but the two leslies have a different space generator and speaker setup. Is that true?
Yes. The amp is itself called a Model 102 - and is present in both the 102 and 103. It is the speaker and space generator setup / switching box / channeling/etc. that is different.



If so, are you saying in your first reply below that 2 of the 4 channels in the amplifier in the 103 aren't used at all? I'm a little confused by
2 Red (not used)
3 Yellow (not used)
4 Orange Main C Channel (Amplifier 2)
5 Green Main C# Channel (Amplifier 3)

Does pin 4 Orange correlate to channel 2 in the amplifier? Is that what you mean by (Amplifier 2)?
Does pin 5 Green correlate to channel 3 in the amplifier? Is that what you mean by (Amplifier 3)?

Well yes and no. All 4 amps channels are used, but when each of the only two channels enter the amp, they are then phase/mixed, etc. to use two amp channels per input channel.




I'm not familiar with Main C Channel vs. Main C# Channel. What is that exactly?


This is called "Isomonic" separation and is unique to Gulbransens. The notes C,D,E,F#,G#,and A# were in one channel; the notes C#, D#, F, G, A, and B were in another channel. THis prevented intermodulation distortion by mixing 4th and 5th harmonics in the air, rather than in the amp. It is not relevant to the Wurlitzer. BUT ... it is something to keep in mind becuase that is why I was not exactly clear whether you should just use one of the input channels, or both. Becuase if you phase-shift two identical channels they will end up cancelling out in any case. THe schematics and manual explain better than I can. I was experimenting with making a combo preamp for the 103 but never tried using either two identifcal channels, or one single channel. You can experiemnt.



Also, in the Wurlizter, i'm pretty sure the upper and lower keyboards each are on there own seperate channel, and the pedals are on the same channel as one of the keyboards (I forget if its the upper keyboard or lower keyboard). But i'm not aware of any channel splitting regarding strings/reeds vs. flutes/tibias. If there isn't any channel splitting regarding strings/reeds vs. flutes/tibias where does that leave me with the 103, and where would it leave me with the possible use of a 102 if i had one or wanted to get one. I know of a technician who said he had connected 102s to a Wurlitzer 4500 and i remember it sounding great, but the person who owned and played it said it would be playing wonderfully and then suddenly the whole sound would go through a mysterious sudden downgrade. Any ideas on that?

OK if there is no flute/complex separation in the Wurly then the 103 may not be an appropriate speaker. It was made to enhance the complex voices and may not be the best tremulant for tibias. But that is a matter of taste - you may like it. If you do this however you have to make sure that you do not bring the pedals into the 103. Now if you have three channels (upper/lower/pedal) you can try putting each manual into each of the two input channels in the 103 and see what that sounds like. Or only use one manual in the 103 and put your other manual into another speaker (like the 102 if you get one). The pedals would also be carried by the 102.

I have an entire service manual for 102/103 that capt foldback never posted for some reason. If you want a scan let me know and I'll post it up later. I have to get back to my real job now!

- jimmy

[mamooshka]

jimmy, believe it or not i think i understand, reading what you told me about the 103 as i look at the schematic. I looked at my wurlizter schematic and played it tonight through my two 147s and I am 99% sure it just has one channel for the upper keyboard and pedals together going into the 'upper amplifier' and one other channel for the lower keyboard going through the 'lower amplifier'. One of the 147s is carrying nothing but the lower keyboard while the other leslie is carrying the upper keyboard and the pedals. That being the case, sounds like i can really only use the 103 for the lower keyboard, right?. Also, i don't see on the Wurlitzer schematics, or hear any evidence when i play it, of the strings being on one channel and tibias/flutes being on another channel. Also, the Wurlitzer schematic only shows one input into the 'upper amplifier' and one input into the 'lower amplifier'. So i guess all this means the 103 will only be usable for the lower keyboard, and its string and tibia sounds will go there. Sounds like i'd need a 102 for the upper keyboard and pedals and both its strings and tibia/flutes from those will all go through the 102, right?Looks like the Wurlitzer just isn't designed to take full advantage of what the 102s and 103s were designed to do, right? But still, I think it would be a very interesting sound that is far different from what i have with just the two 147s i've got now, do you agree? I should still get the effects (or some of the effects from the space generators, shouldn't I)?

[jimmywilliams]

Yes the 103 can carry your lower manual. That should work fine. Again you would have to experiement with whether you should use both inputs into the 103, or just one. I have heard of it being done both ways; in fact I have seen an adapter (forgot what organ model it was for) that only used one of the inputs. In any case in the 103 you have several different tremulant effects. You need two switches - one for the multi-rank celeste and the other for the "regular" tremolo - and you can combine these for instance just multi-rank celeste, tremolo and multi-rank celeste, just tremolo, or none (straight/stationary). I would be really interested to see how it sounds on the Wurlitzer. And yes if you had a 102 as well you would use that one for your upper manuyal and pedals - but unless you can tap into a spot before they get mixed, you would need to build filter of some sort to split the frequencies before they get to the 2 amp inputs you would use in the 102. The 102 only has one control - tremolo on or off. Remember too that in both of these channels the rotosonic drums are always spinning - "tremolo off" really means you are switching from the drum to a stationary speaker in the cabinet. THe space generator in the 102 does not affect the rotary (flute) channel. It is for the pedals only. There is a jumper that you can switch into circuit so that one of the stationary input channels can go into there too but that as only applicable in its original application where the Rialto K's piano voice would be used. Keep in mind that the 102 could have been used by itself so you had those two additional stationary inputs for the complex c/c# channels. When using the 102/103 pair, of course, you would not put the complex channels into the 102. Hope this helps - and I am very happy to see there is an interest in using these Gulrbansen Leslie cabinets instead of parting them out!