• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Bottlehead vs. Dynaco Pas 3

ducati_EL34 said:
What sort of difference did you notice? I am curious. :scratch2:
Click to expand...

It was very subtle... but I noticed that there was just a bit more 'clarity' to the sound. I asked Roy Mottram who designed the PAS3-Z and he agreed that the preamp is line inverting and said that sometimes reversing the speaker leads help, sometimes not.
 
The percieved sonic differences in polarity depend on the listener and source material, it can be either subtle or profound. I hear it readily and it is profound to me in most circumstances, other experienced listeners profess to being unable to hear it. Regardless it should always be comp'ed as a matter of good practice.
 
Last edited:
I wouldn't even consider using a PAS with the tone controls intact. They add a huge amount of veiling and fog to the sound.
 
bhamham said:
Yea, I just followed Roy's pics on wiring the Alps volume control. My only criticism of the PAS kit is Roy's documentation, or lack of. He was great to answer emails quickly and the pics are good. The build is pretty straightforward, however, I think some docs would go a long way to help build the kit and save a few emails. Maybe he has them now, don't know.

I did PIO1980's recommendation to reverse speaker line polarity and noticed a difference - thanks for that.
Click to expand...

Would you be so kind as to post some close up pictures of your volume pot and the connections? You are right about the documentation or lack of...however it did make me think a little more than usual...I just hope I got it right...
Cheers,
 
At the very least I'm going to disconnect the bass and treble controls on the pas tonight. The VTA kit is the one I'm leaning towards. Seems like a bargain compared to the others out there.
 
a point of interest, I up graded the output caps to Wima's on my VTA PAS3-Z they were only a couple of bucks more....now I'm thinking about something even better....
Kirk
 
Wow, last time I looked at roys site he didnt have the SP-6 kits for a PAS-3 chassis...cause ive was eyeing them for a while. Prolly gonna have to snatch one up and my PAS-3 needs a refurb, and i dont really wanna restuff the stock boards, they are kinda toast, and some non original power trans with slightly of voltages. But its got 4 good tele's in it. And it matches the ST-70 and FM-3 i have. Now i know what ill be doing with it, heh. But didnt he used to have replacement rca boards for the ins and outs? you cant plug anything into anything if they are next to eachother, heh. And I cant find them on the site

Mark

Mark
 
kirkleclaire said:
Would you be so kind as to post some close up pictures of your volume pot and the connections? You are right about the documentation or lack of...however it did make me think a little more than usual...I just hope I got it right...
Cheers,
Click to expand...

Here you go, Kirk. Let me know if you need any at different angles or want a description of where a particular wire goes.

Best wishes,
Bruce

IMG_6179.jpg



IMG_6182.jpg



IMG_6184.jpg



IMG_6180.jpg
 
Last edited:
coffee123 said:
Wow, last time I looked at roys site he didnt have the SP-6 kits for a PAS-3 chassis...cause ive was eyeing them for a while. Prolly gonna have to snatch one up and my PAS-3 needs a refurb, and i dont really wanna restuff the stock boards, they are kinda toast, and some non original power trans with slightly of voltages. But its got 4 good tele's in it. And it matches the ST-70 and FM-3 i have. Now i know what ill be doing with it, heh. But didnt he used to have replacement rca boards for the ins and outs? you cant plug anything into anything if they are next to eachother, heh. And I cant find them on the site

Mark
Click to expand...

Hi Mark,

The I/O Jack Bd is about half way down: http://www.tubes4hifi.com/PAS3.htm
I went with it and the Alps controls and selector switch.

It uses 12AU7s (lower gain) in the line stage and 12AX7s for the phono. Your Tele's are probably 12AX7s?

Bruce
 
Hats off to Bruce for the great quad of Russian 6pe3's!!! All the way from across the pond. Thanks! He's the guy who puts the "Karma" in Audiokarma...Thanks also for the close ups of the volume pots.
...I have to say the VTA dynaco paired with the PAS3-Z is now sounding teriffic, I want to compare with the Dynamutt Dynaco with the new tubes and will post my thoughts soon,
Cheers
 
kirkleclaire said:
...I have to say the VTA dynaco paired with the PAS3-Z is now sounding teriffic, I want to compare with the Dynamutt Dynaco with the new tubes and will post my thoughts soon,
Cheers
Click to expand...

Looking forward to that, Kirk. Got to get my Dynamutt project going but I've so much going on now. Man, where does the time go?
 
Anyone try the Norman Koren PAS mods yet?

Very lovely sounding pair, the mainboard and the phono.

Cheers!
 
Geek said:
Anyone try the Norman Koren PAS mods yet?

Very lovely sounding pair, the mainboard and the phono.

Cheers!
Click to expand...

I saw your posts @ the other site. Be super nice to try.

My thought, seeing as mine isn't bound by the origanal box. Is to add a 2nd phono board, and run mono ye mono, thus recrossing signals for a balanced attack.
Do I stand a chance? Is this irrational-plausible? I just like the seperation of signal as a nice idea.
 
If you are going to run something as nice as a Blue Point, neither,:no: Look at the Hagerman line up. He's the best out there with no close second.
 
Cool, I have a stack of PAS2s here at least 4 deep that I could not make listenable, and my bottlehead doesn't even use the stock PT any longer, and it's tube rectified.:D It sounds ok though:music:
 
I used a modded PAS 3 for about 10 years. I did love the sound. I now have a Seduction.

The Seduction uses passive RIAA eq between the stages whereas the PAS uses active RIAA eq from the output to the input, i.e. feedback. This causes the eq to change as the tubes age. Passive eq doesn't change with tube aging.

Even if you have replaced every component in your PAS phono stage I would wager that the Seduction will sound more open and be quieter.
 
Grainger49 said:
I used a modded PAS 3 for about 10 years. I did love the sound. I now have a Seduction.

The Seduction uses passive RIAA eq between the stages whereas the PAS uses active RIAA eq from the output to the input, i.e. feedback. This causes the eq to change as the tubes age. Passive eq doesn't change with tube aging.

Even if you have replaced every component in your PAS phono stage I would wager that the Seduction will sound more open and be quieter.
Click to expand...

The PAS RIAA is mounted on the selector switch as well, and is very inaccurate. There are mods out the that will fix that problem though.
 
You must log in or register to reply here.
Back
Top Bottom