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Mk II with suitcase speaker Question

Started by Kbjazzman, July 11, 2009, 10:53:17 AM

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Kbjazzman

If I would like to get this 2 things work together what should I do? I try to connect cable from out put to input of this unit but sound is very weak. After I've search in this forum it's seems that I need a preamp unit install to convert it to be suitcase model. Is that right or I need another part to get it work together as well.  
Here is the pic






pianotuner steveo

How weak is it? Have you tested the amp with any other input devices, such as a guitar or even an ipod to be sure the amp works properly?

I think this amp is 50w per channel (?)..........
1960 Wurlitzer model 700 EP
1968 Gibson G101 Combo organ
1975 Rhodes Piano Bass
1979 Wurlitzer 206A EP
2009 73A Rhodes Mark 7
2009 Korg SV-1 73
2017 Yamaha P255
2020 Kawai CA99
....and a few guitars...

Kbjazzman

Hi Pianotuner steveo
it's still can be play... but the bass note hardly play out when I switch to Mk V....
I get the stronger vol. but still not have enough vol. to normal condition (compare to my Roland JC 120 ) This baby have 4 speakers it should louder....I'm I right?
I never see the actual suicase amp before. I'll take a photo of inside the unit for ref. By the way If somebody have picture of original speaker of this model please guide me. I'm not sure that the speaker inside this unit is original or it's the new one Coz' I don't see the blue fender sticker on each speaker.

Ben Bove

The problem is - you do need a preamp to make the cabinet louder.

Right now, if you just plug a stage piano into the "input" on the cabinet, you only get the weak level of the stage piano.  It is probably the same if you plug your Mark V into the cabinet too.

The preamp operates the volume.  However if you're just plugging a guitar, keyboard, or other into the cabinet witih a 1/4" cable it will be quiet, no volume adjustments.

You don't need the actual Rhodes preamp though if you're having trouble finding this.  Simply plug the Stage into some kind of mixer, turn up the gain, and run mixer into speaker cabinet.  Or any other amplifying preamp.
Retro Rentals & Restorations
Vintage Music Gear

http://www.retrorentals.net
310-926-5799
info@retrorentals.net

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IG: @RetroRentalsNet

Kbjazzman

Thanks bjammerz
At first I thought suitcase amp come with preamp circuit build in but  Last night I try to hook it up with mic preamp like you said and find out that  my Joe meek VC1 "The brick" is a good pair with my MkV and the suitcase can show their power now.

At this moment I still have some doubt about 4 speakers inside the unit  I'm not sure that this speaker was replaced from the previous owner or not?? so...I will post my pic for you guys ref. Please advise me about this issue too. Thanks in advance



Ben Bove

They do look like the original speakers - I believe they used Rola or other brand later in 70s and 80s.  They don't have the blue fender sticker like early models, or like Jensens.

I have seen similar like yours
Retro Rentals & Restorations
Vintage Music Gear

http://www.retrorentals.net
310-926-5799
info@retrorentals.net

FB: https://www.facebook.com/retrorentals.net/
IG: @RetroRentalsNet

Kbjazzman

Thank you very much bjammerz for the info. Is good to know that this unit is original one.

pianotuner steveo

Bjammerz, My speakers in my FR7710 are different.They have a goldish/copperish colored frame. Did they use different speakers in different years or did they use whatever was available for the lot they were building at the time? Is there any way to'date' my amp?
1960 Wurlitzer model 700 EP
1968 Gibson G101 Combo organ
1975 Rhodes Piano Bass
1979 Wurlitzer 206A EP
2009 73A Rhodes Mark 7
2009 Korg SV-1 73
2017 Yamaha P255
2020 Kawai CA99
....and a few guitars...

Ben Bove

There were a few different used but I have seen as pictured above in later model amps, and as pictured below in the late 70s.  unfortunately it's much tougher to follow speakers as they're locked inside the cabinet and most people don't know / won't open them to get info.

It is possible they used a speaker like you're describing, but they were often replaced by other ppl as well (the JBL upgrade was common among others).

The only way really to date a bottom amp cabinet is by the amp serial number, and speaker codes for whatever company they refer to.  I could possibly help match up if you had speaker info against your amp serial.


ROLA (285) Speakers from 1977 cabinet:




CTS (137) Speakers from a '79:



Retro Rentals & Restorations
Vintage Music Gear

http://www.retrorentals.net
310-926-5799
info@retrorentals.net

FB: https://www.facebook.com/retrorentals.net/
IG: @RetroRentalsNet

pianotuner steveo

OK here are the numbers on mine, they are 8ohms also.

137  7848 005379
1960 Wurlitzer model 700 EP
1968 Gibson G101 Combo organ
1975 Rhodes Piano Bass
1979 Wurlitzer 206A EP
2009 73A Rhodes Mark 7
2009 Korg SV-1 73
2017 Yamaha P255
2020 Kawai CA99
....and a few guitars...

Ben Bove

the 137 connotation is CTS speakers, I believe 7848 is 48th week from 1978 but I'm not a speaker expert on codes so correct me anyone if I'm wrong.

Common Guitar Speaker Manufacturers:
67 = Eminence
137 = CTS (Chicago Telephone Supply)
220 = Jenson
285 = Rola
308 = Stromberg-Carlson
328 = Utah
336 = Western Electric
391 = Altec-Lansing
416 = Heath
465 = Oxford
589 = Bogen
649 = Electro-Voice

I've edited the post above - a 1977 cabinet with Rola speakers, a 1979 with CTS according to codes.

An interesting note from:
http://www.provide.net/~cfh/pots.html

Fender Products.

"During the 1950's, Fender used mostly Stackpole (#304) pots. Then in roughly early 1963, they changed to CTS (#137) pots. In 1967 (after CBS bought Fender), Fender bought a HUGE supply of pots from CTS. This supply lasted for over five years. So guitars and amps made as late as 1973 can still have 1967 date codes from this huge 1967 stocking.
All during Fender's life as an amplifier maker, then used speakers made by Jensen (#220), CTS (#137), Oxford (#465), Utah (#328) and Altec-Lansing (#391). Till about 1961, Jensen was the only Fender speaker supplier. Then from 1962 and later you see Fender using speakers from all the above mentioned makers. "


So we could probably get a general idea when certain makers were used, but it's probably very sporatic.
Retro Rentals & Restorations
Vintage Music Gear

http://www.retrorentals.net
310-926-5799
info@retrorentals.net

FB: https://www.facebook.com/retrorentals.net/
IG: @RetroRentalsNet

Kbjazzman

Wow ..... a lot of info. about speaker. I've learn a lot. Thanks

suitcase'81

Bjammerz,
you never cease to amaze me.
This man's got knowledge!
"All musicians are subconsciously mathematicians."

pianotuner steveo

Awesome info, Bjammerz. Are any of those speaker brands preferred over others?
1960 Wurlitzer model 700 EP
1968 Gibson G101 Combo organ
1975 Rhodes Piano Bass
1979 Wurlitzer 206A EP
2009 73A Rhodes Mark 7
2009 Korg SV-1 73
2017 Yamaha P255
2020 Kawai CA99
....and a few guitars...

Ben Bove

I don't know exactly.  There really hasn't been any kind of shotgun-test of swapping the best speakers for the cabinets.  It's especially difficult to do this on the 4pin cabinets as they're 32Ohm speakers, so you're pretty restricted.  but they certainly weren't the most expensive, top of the line speakers installed in these mass produced instruments.

But for the FR7710 amp cabinets, we could possibly see what the best 8ohms might be.  

The best thing first though, really, would be to have the ideal preamp / EQ set up, then speakers tested.  Problem being that the factory preamps don't really capture the best EQ curve the Rhodes harp puts out.  When treble is boosted, it boosts too high of frequency and you get more hiss than rhodes treble.  So, you'd want the best sound first before you amp it...

It's an interesting thing to optimize the suitcases like that.
Retro Rentals & Restorations
Vintage Music Gear

http://www.retrorentals.net
310-926-5799
info@retrorentals.net

FB: https://www.facebook.com/retrorentals.net/
IG: @RetroRentalsNet

suitcase'81

I'd love to help out with a comparison.
anything to keep bjammerz's database growing and understanding more of the instrument we all fell in love with..
I've got an FR7710 amp/cabinet
I'll open it up, check the numbers on the speakers
and we'll go from there.

any more volunteers?
sign up here!
:D
"All musicians are subconsciously mathematicians."