Fake Alps Blue?

[PakProtector]

hey-Hey!!!,
How does one recognize one of the fake Alps Blue volume pots. I am looking to buy a few 50k for the next linestage projects and don't want the fakes. Anybody have a good source? Looked at ebay and while some say 'Made in Japan' I want to be sure.
cheers,
Douglas

 

[jaymanaa]

I've wondered about this myself. The last batch I bought (from Japan) certainly appear and feel like the real thing.

 

[Hi-FiGuy]

I use to sell ALPS 25K pots on eBay. What I noticed is the real ALPS pots have use a serif font. In the lower left corner is the pot size and taper code. In the lower right is the pot value and taper type. This is only helpful if the ebayer shows you the label on the back. Another thing, according to the ALPS website they never made an RK27 blue pot with a knurled shaft or "stepped feel". The part number on the pot will be 704t, 706t, etc. and the real thing never used an RH or RK part number on the device. Watch out for those fakes!!

 

[dgwojo]

They're probably not real Apls but I get the stepped blues from seller "handgun" on that web site, I find the stereo 100k with loudness taps work best and track very evenly on both channels for tube amps, Dave.

 

[DaWoofer]

Dgwogo- So, that pictured on is a fake? I bought one just like it last year with the numbers RH2702 and it seems to work OK. The only problem I found with it is when its turned all the way down it seems like there is a short or something, it just doesn't cut out right like it should. Have you noticed this same action?

 

[dgwojo]

Dgwogo- So, that pictured on is a fake? I bought one just like it last year with the numbers RH2702 and it seems to work OK. The only problem I found with it is when its turned all the way down it seems like there is a short or something, it just doesn't cut out right like it should. Have you noticed this same action?

Hi,
I'm not sure these are a fake or not but mine works very well, I bought similar ones direct from sellers in China and they were terrible, I like these because they had an internal view of how they're constructed on that auction site. Mine have no quirks at any setting, I'm using them on a tube amp with .47uf coupling caps, the loudness tap is not being used. :thmbsp:

 

[coaxial]

They're probably not real Apls but I get the stepped blues from seller "handgun" on that web site, I find the stereo 100k with loudness taps work best and track very evenly on both channels for tube amps, Dave.

Do you have a wiring diagram for this pot? I am about to install mine and just wanted to make sure I do it right..

 

[Rockyhill]

ALPS Blue Velvet WITH Serif

Here's an ALPS 100k that has the aforementioned Serif font. Purchased from parts connexion. Shaft is not knurled nor does it cut out at lowest ccw position.

 

[Hi-FiGuy]

YUP!! Thats the real deal.

 

[coaxial]

So what I meant was I am trying to replace my volume pot on my yaqin ms-6v6 Attached are the schematics for the input and volume board. Along with an alps wiring diagram however since mine is not the true alps (blue alps 100k RH2702) I am not sure if the connections are correct if you could cross check it would be appreciated.

Alps Diagram:

On the input side XS5 B is wired to:

1. rear #3 (right channel input)
2. Chassis ground
3. front #3 (left channel input)

And on the output side

XS4-R & L are wired to
1. Left or right signal output
2. Left or right sound earth.

When I hooked up everything I could hear audio but faintly Increasing volume only added more noise no music though. I think the main issue is the earth connections are not grounded to chassis I will try that next. is there any other recommendations that you would have?

Thank you.

 

[dgwojo]

Do you have a wiring diagram for this pot? I am about to install mine and just wanted to make sure I do it right..

I received this from HANDGUN and I wired mine this way and it works just fine;
Dave:

Hello!


PIN ASSIGNMENT

Pin 1 ? Ground
Pin 2 ? Signal Out
Pin 3 ? Signal In
Pin 4 ? Loudness Tap (Optional)

I hope this helps.

Norm



- handgun

 

[coaxial]

I received this from HANDGUN and I wired mine this way and it works just fine;
Dave:

Hello!


PIN ASSIGNMENT

Pin 1 ? Ground
Pin 2 ? Signal Out
Pin 3 ? Signal In
Pin 4 ? Loudness Tap (Optional)

I hope this helps.

Norm



- handgun

It works thanks!

 

[quadtech]

To answer the o/p, the Alps 100k pot is available from Mouser, Item #
688-RK27112S20C0A104

 

[Rockyhill]

Partsconnexion:

ALPS Blue Velvet - STEREO Conductive
Plastic Potentiometer, 100K, audio/log
taper volume controls

ALPS-64605

$17.95

 

[vintess]

Alps Pinouts

It works thanks!

I know that this is an old thread, but maybe this will help others who are looking for the Alps pinout assignments.

For 6 pin Alps (without loudness pinouts)
Pin 1: (from right to left; looking at the pot at the back where the label is): Left Channel Ground
Pin 2: Right Channel Output
Pin 3: Right Channel Input
Pin 4: Right Channel Ground
Pin 5: Left Channel Output
Pin 6: Left Channel Input

(For those Alps models with loudness taps, then pot will have two extra pinouts (a #4, being the right channel loudness tap and a #8, being the left channel loudness tap).

In general, most pots will have one side (outside taps) being ground and the other outside taps being the input. The center taps are usually the outputs (wipers).

For those that are replacing the old, outdated volume pots on the Dynaco PAS series, keep in mind that the Alps has the inside (against the front panel ares facing out of the units/or another way of putting it is the taps immediately next to the threaded shaft portion) AS THE LEFT CHANNEL SECTION. Whereas the ORIGINAL Dynaco POT HAD THE RIGHT CHANNEL SECTION IN THIS LOCATION! Just something to keep in mind...

I am attaching a schematic (which I cannot take credit for, I can't remember where I lifted it from, but it was somewhere on the Web...If I could remember, I would post credit to its author...) which might help further.
Hope this helps...

 

[hifix]

I wish i found this thread sooner :-(

 

[datafone]

hey-Hey!!!,
How does one recognize one of the fake Alps Blue volume pots. I am looking to buy a few 50k for the next linestage projects and don't want the fakes. Anybody have a good source? Looked at ebay and while some say 'Made in Japan' I want to be sure.
cheers,
Douglas

Grab the Cosmos pots instead, way better than the blue alps and cheap. Channel matching is very good with these.

search "Cosmos Tocos Potentiometer RV24YG 24mm A 50KΩ x2 Log Japan" on fleabay

About 15 bucks posted.

 

[restorer-john]

How are they 'better' than an Alps blue? Their tracking is +/-10% between tracks which means up to 20% difference. Not much good for a stereo amp if you ask me.

Grab the Cosmos pots instead, way better than the blue alps and cheap. Channel matching is very good with these.

search "Cosmos Tocos Potentiometer RV24YG 24mm A 50KΩ x2 Log Japan" on fleabay

About 15 bucks posted.

 

[jaymanaa]

Stepped attenuators or autoformer thingies is the way to go for uber hi fi. RS sells some little alps pots for a couple bux, so you can buy like ten, then cull the ones that track good. Or, you can always go with two pots, but that can drive you insane pretty quick. If you want to see a really amazing volume control system, look at the schematic for a Hafler Iris.

 

[Dan ʕ•ᴥ•ʔ]

Now THESE are really good pots! :yes: