Is there an R2017B amplifier that cannot be stereo revision?

[daijiiwata]

This may be a post that will be of interest to all of you.



I am assuming that this is an R2017B amp for AMI, possibly for use with Lyric.

I was originally aware that this series would have another connector as a means of stereo revision,but this amp does not.

(As you can see, I can only find a 9-pin connector.)



I only have a schematic of the R2777 in my possession, so I have no convincing information about the occasion.



I thought it was basically designed for stereo revision,

but for this amp, is that not the case and is it intended for mono only?

To be precise, this is an amplifier made by Tsugami AMI in Japan.

Therefore, perhaps this shape was intended as a cost-cutting measure?

[Hildegard]

Hi Daiji,

Amplifier 2017B was used in models Continental 1 and Lyric.
The complete amp unit is a modular style, AMI called it "Multi-Use Amplifier". So operators could swap from mono to stereo or vice versa right on location by plug-in.

2017B is the basic power amplifier only.
For mono the module L2156 was added onto the chassis (empty space on your photo).
For stereo the modules "Stereo Power L-2155" and "Stereo Control R-2020" were needed.

You can read here a little bit:
www.jukebox-world.de/Forum/Archiv/AMI/AMI-AMP-2017.htm


Hildegard

[jukenorman]

Hi Hildegard,
That amplifier is slightly different from what we normally see in a 2017B in that it uses different output tubes (valves). The pictures aren't particularly clear but it looks like 7189A instead of 6973 - but probably the same basic design.

Norman.

[Hildegard]

Hi Norman,

You are right about 7189A, I did not compare the valves. 5U4GB and 12AU7 are same.
So what could have been the advantages of using 7189A instead of 6973?

I just saw that we even have a picture of a Tsugami Lyric: www.jukebox-world.de/Forum/Archiv/Welt/Tsugami_Lyric.htm
It does have red mechanism covers, coin glass, and buttons, not green and a new front window.

Hildegard

[jukenorman]

Hi Hildegard,
Probably no advantage other than availability and cost, I would imagine! Much the same reason that the US Rock-Ola Tempo amplifiers had 6973 and the German Nova ones had EL84.

Norman.

[daijiiwata]

I am very happy that you are all interested in this lol.

I am aware of the fact that the output tube has changed to 7189A instead of 6973.
I am aware that the grid bias voltage is slightly different, but the other specifications are similar.

In Japan at that time, many vacuum tubes were manufactured and sold,
so there may have been a lot of flexibility in the selection of output tubes.

I don't believe there is any information on Tsugami AMI amplifiers available to the world.
For example, regarding the Tsugami version of the R2620 amplifier, the output tube was changed to a 7591 (GT version of the 7868),
the output transformer was made by Sansui,
and other information that I believe is not well known to you.
(It is hard to see in the photo, but there is a Sansui nameplate attached to the transformer case of the amplifier.)

In any case, when we looked at the actual amplifier this time,
we found many problems scattered among the components and wiring,
and our goal is to repair it to the condition of a conventional 2017 amplifier.

[Hildegard]

Hello Norman,
I guess you are right about the reason for using 7189A back then. At least it makes sense and import rules were an important issue back then.
NOVA imported jukeboxes in parts and added with some own units (e.g. amplifier, power supply, cartridges) which might have saved quite some money. UK did so too when I know right.

Hello Daiji,
If you do not find any Tsugami information who else should be able? I don't know of any.
Maybe the AMI schematic diagram of R-2017 will help you to rebuild your amp.

Would you mind if I add your photos and information to our Tsugami Lyric site in the archive?
Do you know of other AMIs by Tsugami? You talk about R-2620 which were used in model JAL and JBM.

Hildegard

[daijiiwata]

Hello Hildegard Sensei.

Just a moment please!
The amp in the image I sent you this time, but there are still too many mistakes in it, and if I publish it, it may not be helpful for anyone to see it.
(It may be an intervention by the repairman at the time)
I actually have a few in stock and will show them to you soon.

I am not sure whether to use R-2017 or R-2777 as a reference object for repair.
They both have almost the same content, but the only difference is in the parts used in V1.
I would normally presume that R-2777 is revised and more improved.

We have room to choose either way....I guess the rest is just my preference?lol

[Hildegard]

Thank you, Daiji.
Sutre I will be happy to wait for more or other information coming from you.
Good luck with te reapir resp. rebuilding - Hildegard