DCB1 Build

[sachu888]

Make sure you don't buy D shall shaped shaft. It will not for a normal volume knob.

Regards
Sachin

 

[magma]

2 Pcs of Dact Type 21 Stepped Attenuator 50K 2A3 | eBay
As per some Diy audio members this sounds better than Alps Blue Valvate. Fm, Sann, Omishra are using same and have confirmed better than LSA.

Regards
Sachin

sachu
the LSA is not difficult to trump

joshuas Citec sounded better than the LSA

i have the Blu velvet and have tried the 12$ stepped attenuater

though im not blankly refuting anyones claim on DIYA
But more often than not
most DIYA members have been buying blue velvets from china and ebay
ALL of these are fakes

its not fair comparing a fake blue velvet to another pot

the fake blue velvet costs 12-14$ which is exactly the same as the stepped attenuater
it would not be surprising that they sound the same or even if the stepped sounds better

but comparing that with a gen blue velvet ?

the Gen Alps
as far as i know are availbel in retail only from a German seller
who charges 35 Euro

 

[sachu888]

I am well aware about fake parts from China or Ebay.

Regards
Sachin

 

[keith_correa]

the Gen Alps
as far as i know are availbel in retail only from a German seller
who charges 35 Euro

Also available at partsconnexion and angela among MANY others.

Closer home

 

[magma]

ahem......

keith

at least two of the above links are re selling the chinese alps

 

[jls001]

The DACT pots look like one channel. Any idea if there are dual ganged stereo models? If we were to use one pot per channel, it would entail having to make another hole in the front panel, which isn't all that convenient on an already built cabinet.

 

[sachu888]

Joshua, the link I have posted is for a stereo pot.

Regards
Sachin

 

[jls001]

Thanks. I zoomed the pic and can now see that it is indeed stereo.

 

[omishra]

BTW, I used 20K pot. Link posted by Sachin is now started landing on 50K pot.

 

[mahiruha]

Hi,
I am looking for a simple passive pre amp which can handle 1 Kohm load output impedance from source and 10Kohm input impedance of power amplifier.Can this DCB1 handle this impedance requirement?
Thanks.

 

[captrajesh]

Fm Sann, Omishra are using same and have confirmed better than LSA.

the LSA is not difficult to trump

joshuas Citec sounded better than the LSA

Is it!!! News to me.

Gen(uine) Alps as far as i know are available in retail only from a German seller who charges 35 Euro

Alps has an Indian Office which is listed on their website. Hence they sure would be having local distribution channels as well.

ALPS ELECTRIC (INDIA) PVT. LTD.
HEAD OFFICE D-26&27, Infocity-?, GTPL, Sector-33, Gurgaon-122001, Haryana
+91-124-2373024+91-124-2373025

 

[keith_correa]

BTW, I used 20K pot. Link posted by Sachin is now started landing on 50K pot.

Is 20K better than 50K in this case?

 

[sachu888]

I have recently listened to 50k ebay dact type pot in DCB1. I liked it over LSA. I also have 20k ebay DACT type pot sent by Omishra. I will try it soon.

Regards
Sachin

 

[omishra]

Is 20K better than 50K in this case?

I felt so. Actually I was trying for 25K, but settled with 20K. And it was worth.

 

[jls001]

I tried 20K on DCB1 but lost bass weight so reverted to 50K log.

 

[IndianEars]

Super Indian Site for Audiophile DIY stuff

theaudiocrafts

They even have the Apls Blue Velvet Pots... upto 4 Ganged and Moterised... Decent price.... Check Here

Exclusive Reference Quality Products

 

[arunlouie]

From an Indian DIY store

Potentiometers

Also for remote controlled Input selector + Volume controller with Alps

Volume Control modules

Seems decent quality.

 

[anilva]

One of the problems I have been having with a DCB1 is that there is quite a bit of wild swing in the output offset resulting in a big cone movement at the time of start up. This could be just the power supply stabilizing. Since this is direct coupled, I am sure this offset is reflecting in my Pass Power amp output.

Did anyone experience this kind of a problem. I am thinking of passing the AC mains through a NTC to slow down the current rush. Ideal would be a delayed output switch which mutes the signal on poweron. Most of the high end preamps have this.

Cheers.

 

[omishra]

Actually it should be create problem. I analysed this. When we do cold start of preamp, all caps start charging and PS output voltage increase. It stabilizes at regulated level. During this time, JFETs pairs in each channel see increasing dual voltage across it but conduct similarly. So not output offset change at DCB1 unless input influences anything.

But delayed relay like switch could be good idea.

 

[sachu888]

One of my friend from Australia has completed his build. He had picked up kits and cab during his recent visit to India. Raghu has provided the cab.
He has additionally added a bypass circuit board, when you select input 5 it bypasses the preamp and switches straight to the output, he needed this because he had 2 devices that already had preamps















Bypass relay


With Amp Camp


Regards
Sachin