3D imaging pre-amp

[jake111]

Bonzo,
Please post your impressions. I don't use headphones much with my SEX amp, but if this has good affect on near too field I just might build one.
Jess

[aragorn723]

Bonzo,

Yes, please do    What are the Russian PIO caps called/who sells them?  I'm looking for the parts to build this thing now, that 1 nf cap = .001 uf, right?  Thanks!

Dave

[Chris65]

Russian K40Y-9 PIO's. They're all over Fleabay, other places too.
1 nF = 0.001uF = 1000pF

[aragorn723]

Are they similar sounding to the Russian K75-10's?  I have some of those as coupling caps in my quickie.

Dave

[Chris65]

Not compared them directly, but this article has reviews/thoughts on the Russian capacitors (as well as many others!).http://www.enjoythemusic.com/diy/0708/capacitor1.htm

[aragorn723]

thanks..  just one more question, how critical are the voltage/wattage/tolerance ratings on the components?  I have some Vishay Dale 1/8 watt 100k resistors already, but might need some help figuring out what voltage/wattage/tolerances to buy. 

Dave

[Bonzo]

@aragorn723
I bought caps on fleabay, searching for "___uF matched" (fill the correct value). The search will return you almost only russian PIO caps. Please take note that russian 1nf caps have big lead legs, you'll need to enlarge pcb holes and trim a bit the legs to accomodate them. I don't know about resistors, I used 1/4w but I think 1/8 will be ok too

@jake111
I'll try with a simple setup: quickie, t-amp and fostex fe103 on my desk. Test disc "Misterioso"...  . Will report later.

[Bonzo]

might need some help figuring out what voltage/wattage/tolerances to buy. 

I forgot to add thath it's better to match components between L and R channels (as usual) and that for capacitors the higher the voltage the better.

But given the small capacitance required, you won't have a lot of voltages to choose from anyway.

Ciao!

[aragorn723]

Sounds like the voltage and wattage don't matter much.  So tolerance is probably the same?  Thanks,

Dave

[Bonzo]

Ok,
some quick impressions when using in nearfield setup: no quickie, only ipod touch with direct output > 3D preamp > Fenice 2024 amp > Fostex fe103.
The first thing I noticed was the apparent lack of low frequencies, voices and trumpets were thinner than before, but after a moment the effect of broadening the sounstage was there! And made me forget the harshness

My ears were at 1m from the speakers, so after a while it was very fadiguing to keep on listening anyway.

I wish I had my Yamaha small monitor at home, just to try a more bass friendly speakers.

The "3D effect" added, however, is really interesting!

[aragorn723]

Hi Bonzo,

Have you put a lot of time on the components?  To me that sounds like they aren't burned in yet (I had a similar experience with the Quickie before burn-in).

Dave

[jake111]

Thanks, Bonzo
I think I'll build one.
Jess

[Bonzo]

Have you put a lot of time on the components?  To me that sounds like they aren't burned in yet (I had a similar experience with the Quickie before burn-in).

Not at all aragorn...maybe is too early to judge...

I'll give it a burn-in period connected to my tv, thank you for the suggestion!

[aragorn723]

Please let us know your thoughts when it's burned in!

Dave

[Bonzo]

ATM it's still hooked to my bedroom tv setup.
Speakers are close to each other (no stereo image needed), but this preamp in some way made the sound more "open", it seems it's acting like this software: http://www.ambiophonics.org/index.html