Vintage Vibe's 4 Pin Peterson Vibrato LDR Conversion Kit

[Tim Hodges]

So this kit is designed to replace the old bulb vibrato system in your Peterson Preamp with optocouplers instead (like the Haigler 5 pin preamp)

I installed this last Thursday and only got round to testing it yesterday with my Master Satellite amp. Soon as I fired it up I was grinning for ear to ear, this is a great piece of kit and makes my life easier knowing that I don't have to go finding those GE bulbs anymore.

Installation was pretty simple, remove the Phillips LDR's and the original bulbs (including the holders) replace 4 resistors on the board and drill a hole in the ground of the PCB.

I think in total it took about 10 minutes to do.

It sounds exactly the same as before, really smooth and buttery, in fact better as previously I had that popping problem that would occur whenever you engage the vibrato (and would pop to the speed of the vibrato) now that's disappeared so I'm glad that's been fixed too. I'm buying another one of these kits in a couple of months to put on the other piano.

All in all highly recommended!

[Tim Hodges]

I removed the piano out of the case for some alterations and decided to record what the preamp sounds like through one of my Satellite speakers. This is the preamp on the lowest possible volume (it's that loud)

http://instagram.com/p/oGFINCGp9p/

[Max Brink]

Ah, man. I'd hate to see the bulbs go, though! That's what makes the Peterson Vibrato!

I'm low at the moment but I have never had much trouble stocking the original bulbs and if anyone wants to keep the circuit true to the original design just shoot me a call.

[Tim Hodges]

Ah, man. I'd hate to see the bulbs go, though! That's what makes the Peterson Vibrato!

I'm low at the moment but I have never had much trouble stocking the original bulbs and if anyone wants to keep the circuit true to the original design just shoot me a call.

Hey Max, I agree it's nice to keep the original bulbs but really I rarely have the pre-amp open to notice them going on and off so it's really for peace of mind and future proofing. Also it's fixed that vibrato popping too that's a big plus.

Good to know that you still have the bulbs just in case for my other preamp.

[Student Rhodes]

I'd love to hear your pre-amp with both speakers.   
The popping on the Petersons can be a drag, but there are mods for that.  Anyone tried or recommend one?

By the way, a friend has a MK II suitcase, and if you dial the intensity back, which softens the harshness of the stereo ping/pong, it's not as bad as some would think.

[8675309]

Tjh392 did you by chance rebuild your Peterson prior to the installation?  Just curious..
Keep in mind - at this point in time - any electrolytic cap is way past its usable life and should be replaced. This goes for amps, preamps- especially a peterson at 35+ years old..

I've played quite a few Rhodes with petersons which were properly rebuilt which made nothing but sweet ping/pong vibrato, no click or thump.


My apologies but: I must state that install procedure is Kind of dicey in my opinion, maybe some other folks can chime in here with their single sided pcb work stories..
Drilling into brittle single sided pcb material is generally a big NO-NO!

Single sided boards are extremely fragile. You have to watch your soldering temps as its easy to burn traces right off the board which leads to having to repair traces which is an art form in itself to accomplish. It would only be too easy to over stress the board while drilling. Wish they figured out a better way! An experienced tech might know/understand this, but is this info documented so your average Joe doesn't break out his 90Watt Well soldering/ray gun, pipe solder & Pop's trusty old Black & Decker 1/2 H.P. Drill to install this?

Allot of folks Nose dive into D.I.Y. stuff without full knowledge like the wonders of working with old single sided pcb material? or re-cap before modify? Just sayin..


Have any other Clips?

[Tim Hodges]

Yes I recapped the board as you're quite right the components are way past their life expectancy.

I can see why you might be concerned with drilling into the trace of the ground but done properly you should have no problems. The trace for the ground on the PCB is quite wide and if using a dremmel with a fine drillbit you shouldn't have any problems with the PCB (obviously you want to avoid using a larger drill)

Here's a link to the video for installing the kit:

Fender Rhodes Peterson Pre Amp LDR Vibrato Retrofit

[Max Brink]

I've played quite a few Rhodes with petersons which were properly rebuilt which made nothing but sweet ping/pong vibrato, no click or thump.

The bulb vibrato circuit sounds great when it is functioning properly. Given the affordable price of the bulbs and their long expected lifespan this LED modification leaves me scratching my head...

On a blind test I don't doubt that it sounds like a good vibrato circuit, because there are great sounding LED vibrato circuits, I just don't believe that it does the original Rhodes sound justice to replace the bulbs with LEDs. Players gush over the Peterson's vibrato as soon as it's switched on in ways that I have never heard them gush over the Janus' vibrato or other vibrato circuits.

My apologies but: I must state that install procedure is Kind of dicey in my opinion, maybe some other folks can chime in here with their single sided pcb work stories..

Amen... Some of my biggest repair jobs have resulted from inexperienced DIY repairs or when I have to undue the work of an unqualified tech. Especially with the Peterson's preamp I have seen some really fried boards that would have been just fine if they were in the hands of someone who knew how to properly work on them. Small repairs can turn into big repairs when they're not handled properly.

[Tim Hodges]

The bulb vibrato circuit sounds great when it is functioning properly. Given the affordable price of the bulbs and their long expected lifespan this LED modification leaves me scratching my head...

On a blind test I don't doubt that it sounds like a good vibrato circuit, because there are great sounding LED vibrato circuits, I just don't believe that it does the original Rhodes sound justice to replace the bulbs with LEDs. Players gush over the Peterson's vibrato as soon as it's switched on in ways that I have never heard them gush over the Janus' vibrato or other vibrato circuits.

I guess this might be down to some of the components on the rest of the board. I'm not too familiar with the exact LDR process but it will only allow the current through the diode when there's a light shining on it allowing the audio on that side. The difference between the new conversion would be that you wouldn't have the fading bulb between switching like you would on a stock Peterson but I can't imagine that would account for much as it wouldn't let much through the diode. I think people tend to confuse the warmth of the sound with the bulbs as if they were like a valve amp much like the argument for vinyl over CD's MP3'S etc.

Amen... Some of my biggest repair jobs have resulted from inexperienced DIY repairs or when I have to undue the work of an unqualified tech. Especially with the Peterson's preamp I have seen some really fried boards that would have been just fine if they were in the hands of someone who knew how to properly work on them. Small repairs can turn into big repairs when they're not handled properly.

Yeah, it depends on experience of the person repairing but obviously if you're not capable or experienced with working on electronics I wouldn't suggest it.

[Chris Carroll]

Our Vibrato modification was made out of necessity by our team of electronic engineers here at Vintage Vibe. At the time of inventing this modification there were zero places that stocked the #19 bulb. To this day, I still do not know a reliable source.

We designed our vibrato modification to be a dead on replacement of the incandescent bulb by mimicking the ramp up and down time of the bulb filament to produce the cat's eye waveform. Side by side tests show #19 bulbs to our Mod is indistinguishable. For those looking for an alternative to the original setup, our Mod is available in kit form for installation in older units, and is present in our Stereo Vibe pre amps and Stereo Vintage Vibe Pianos.

[Student Rhodes]

there were zero places that stocked the #19 bulb. To this day, I still do not know a reliable source.

And from looking around the web it seems we're also in competition for these bulbs with the model train world and juke box enthusiasts. 

If the Peterson uses the 14 volt bulb, here's a place that has them at a very reasonable price.
http://www.lightingzilla.com/eik-41070ek.html

[Max Brink]

And from looking around the web it seems we're also in competition for these bulbs with the model train world and juke box enthusiasts.

Finding a reliable source to keep a large inventory of them around may be hard to do but finding one or two is usually no more than a google search or two phone calls away.

[voltergeist]

Ken Rich has them.

http://kenrichsounds.com/store/index.php?main_page=product_info&cPath=5&products_id=28

[Tim Hodges]

Either way I'm happy with the product. The optocouplers I feel will be more reliable than filament bulbs and they sound exactly the same so that's a win for me. I can see some people will want to keep their Rhodes in stock condition which is cool but I want to make sure that in 30 years this will still be playable without the hassle of trying to source those bulbs which by then may be incredibly difficult to find.

[Olaf]

This ebay seller has "more than 10 available" http://tinyurl.com/ny5tsdf
I just bought 4 of them so I'm good for another 60 years.