Leslie - an unusual mod - What do you think about ?

[kagliostro]

I've find this mod about a single drum Leslie

http://georgewhitfield.co.uk/compression-horn-leslie-hammond-t-202/


https://www.youtube.com/watch?v=7pZFxTRAdsM&feature=youtu.be


Cause my PC speakers (and my ears, I've some problems more of the usual this last days) I'm not able to distinguish the effect of the mod on the sound

Is a mod that is worth doing ?

Please can you report your opinion about ?

Thanks

K

[Ritchie200]

I had a hard time hearing what he was talking about but it looks like he has a simple crossover on a horn that is firing (so to speak) into the output side of the drum?  I would think a speaker with a whizzer cone or a speaker with a tweeter built in would sound better?  If a fuller response is what he is looking for, that would be the way I would go.  That way you get the full effect of the rotor instead of a little blip when the opening swings by.  The way he has it, there is no Doppler effect on the horn.

Many of the smaller spinet Hammonds had a Brilliance tab to give a high freq bump to the larger speaker(s) that were built into the organ.  I think it sounds pretty good IMHO (Hammond knew what they were doing!). However, when I'm running direct into a Marshall I don't use it as it is too peaky sounding to my ears with the distortion.  It may also be too much treble if run into a big Leslie, I don't know.

What he has is still a "poor mans" Leslie effect.  As you know, the mojo of the big Leslie cabinets has to do with the different horn and baffle speeds, different rates of acceleration and deceleration - its more than just adding a crossover and horn.

Jim

[TIMBO]

I think Jim is on the money.
I do hear a difference and how I see it is, it's all about moving sound(ya think) with the added horn its just throwing another frequency into the mix and filling the air with sound. There will also be sound bouncing off the outside of the wheel.
There is also sound being BLOWN around the room, remember that is how a speaker works, moving air.

[kagliostro]

Thanks Ritchie and TIMBO

I had a hard time hearing what he was talking about but it looks like he has a simple crossover on a horn that is firing (so to speak) into the output side of the drum?  I would think a speaker with a whizzer cone or a speaker with a tweeter built in would sound better?

What the guy is talking about is to add some compression to the sound, but I'm not able to recognize nothing like that on the sound, as I told, seems that my PC speaker and my ears are not suitable for that purpose, however what you say seems to be that there isn't a particularly pleasant effect on the sound that worths the effort of the mod

Thanks

Franco

[jjasilli]

What he guy is talking about is to add some compression to the sound
The horn is physically adding both more high-end, and also compression to the high-end.  The horn driver probably can't produce lo frequencies anyway.  The crossover saves the horn driver from being overdriven/overheated by electrical signal that it can't reproduce.

[Ritchie200]

I think what he was referring to was adding a compression driver horn to reproduce the higher freqs.  This is the type of driver used for the horns in the big Leslie cabinets.  I don't think he was referring to obtaining a more compressed sound.  Again, I just think he is going about it all wrong.

Jim

[sluckey]

I think what he was referring to was adding a compression driver horn to reproduce the higher freqs.  This is the type of driver used for the horns in the big Leslie cabinets.  I don't think he was referring to obtaining a more compressed sound.

I agree. That's exactly what I thought he meant. Not compression, just more treble. I definitely hear more treble with the horn connected. I don't really hear much if any Leslie phase shift effect on that extra treble sound. I do like the brighter sound better though.

[kagliostro]

I agree. That's exactly what I thought he meant. Not compression, just more treble. I definitely hear more treble with the horn connected. I don't really hear much if any Leslie phase shift effect on that extra treble sound. I do like the brighter sound better though.

Ciao Steve

do you agree that with a different speaker the effect can be reached without the use of the horn unit ?

Grazie

Franco

[Ritchie200]

This is what I am talking about.  I think those units have an 8" speaker?  You can get an 8" coaxial speaker with a tweeter and even a midrange built right in.  This should give you a full range of response and they will all be firing into the rotor.  Sorry, I was probably not real clear on my description....


Jim

[TIMBO]

Speakers are a suck and see, I had three types to choose from and I found a RESPONCE http://www.diyaudio.com/forums/full-range/126798-fullrange-helper-bass.html
to have the best overall sound

[sluckey]

do you agree that with a different speaker the effect can be reached without the use of the horn unit ?

Yes. Actually, probably even better because you will get the full rotary speaker effect on a full range speaker. I chose to put my bright sounding Weber California 12 in my Leslie. The nature of the Leslie cab will dull down the sound of any speaker. My Celestion speakers sounded dull inside my cab, especially when the scoop was stationary.

[Toxophilite]

I've had several of those rotating drum leslies
They sound really cool but they all lack top end and end up adding a lot of honky mids to the guitar sound
I was really happy to find one which had the actual speaker rotating with no baffle in front of it
The brighter sound in the video sounds better but I don't think I can hear the leslie effect on the top end.
I think you'd need a coaxial speaker with the tweeter cranked to hear it through the baffle, I'm not sure if that woudl work as the top end is directional and the speakers blows right into the drum essentially