[budwisers]

Way back in the days of old I built the Omega II Line preamp kit that was featured in the 1992 audio basics.  Really enjoyed this little preamp, fast forward to 1994/05 when I bought the PC-194 versa-kit II card intending to us it as a phono board.  Never did  .  So I got the bug and pulled my board out and sourced the parts I needed in anticipation of using the power supply from the Omega II kit and this board and making a nice little stand alone phono preamp that I can plug into current preamp.  Based on what I hav read going back to these documents, it sounds like I can power this board off of the original Omega II kit power.  Does anyone have any thoughts on this.  How does this phono card compete with other current phono preamps.  Am I wasting my time?

[dB Cooper]

How good do you need it to be? If you are aiming for State of the Art performance, maybe you would be wasting your time. If you just want to enjoy some vinyl, it would probably be fine. You can buy a lot of music with the money you would spend to get something more "current". Even then your Versa-Kit would probably show up a lot of newer, pricier gear.

Since you brought it up though, I'll toss out a related question: I too have the ca. '92 Versa-Kit multipurpose board, currently configured as a line buffer, and am thinking of rebuilding it in the headphone amp configuration. I was wondering if there is a better op amp choice available now than the AD843's which are in there presently. The improvements over the years, I suspect, have been mainly in the active circuitry which is entirely in the opamp. So could I (or you) get more "modern" performance by "chip rolling"?

Also, Frank was talking not too long ago of reintroducing a multipurpose board that would essentially be the equivalent of a new Versa-Kit, but I haven't heard anything about it for awhile. Wonder if that's still in the works?

I'm sure AVA would have the answers to all these questions...

[G E]

I too have the ca. '92 Versa-Kit multipurpose board, currently configured as a line buffer, and am thinking of rebuilding it in the headphone amp configuration. I was wondering if there is a better op amp choice available now than the AD843's which are in there presently. The improvements over the years, I suspect, have been mainly in the active circuitry which is entirely in the opamp. So could I (or you) get more "modern" performance by "chip rolling"?

I built a headphone amp a couple years back and its sonic signature was influenced by opamp selection.  I recall checking out the 843 in circuit - not bad at all but not the last word in resolution.  A very "solid" sound.   I went with dual AD8610's from Analog Devices.  They also have a stereo version the AD 8620.  I really like its PRT, a very fast chip.  Draws less current than the 843 too, runs cooler.  The AD 8413 (if memory serves) was somewhere between the two chips.  I think Frank uses the TI/BurrBrown OPA 627 in his designs now.  This is a well regarded opamp in the DIY headphone circles.  It tends toward a warmer presentation.

I run Grado 325 headphones and on some of the less-well recorded material the sound can get a little bright with the dual 8610's.  How they would function in the old Versa circuit is a question for which I don't have an answer.

I built a 2nd version of the headphone amp that functions as a preamp for my back speakers in my multi-channel music set up. It also has paired 8610's. It drives an Omega 3 power amp and it is a wonderful pairing.

ge

[budwisers]

Not sure I can answer the chip swap question.  I really just want a good simple phono preamp to enjoy some of my vinyl.  I had looked at other diy kits or boards for like the phonoclone3 and another one from a guy out of canada, but just did not want to spend a whole lot of $$$$.  I feel what I have will be sufficient and is probably right up there with those two.   

[avahifi]

I can built you guys a simple Insight+ headphone amplifier PC card for $150.  I need to know the impedance of the headphones and what will be driving it.

You will need to add a + and - 15V regulated power supply and all the hardware, including the chassis.

Regards,

Frank Van Alstine

[gjs_cds]

I can built you guys a simple Insight+ headphone amplifier PC card for $150.  I need to know the impedance of the headphones and what will be driving it.

You will need to add a + and - 15V regulated power supply and all the hardware, including the chassis.

Regards,

Frank Van Alstine

Frank--wouldn't this also serve as a great little bare-bones pre-amp as well?  (I'm thinking for my office, where I use both cans and some self-amplified loudspeakers.)

[avahifi]

For headphone driver use, assuming the output from a preamp line stage is driving it, we set the little Insight board as a unity gain current amplifier only.  For applications requiring voltage gain, a different configuration is required.  We can supply that too at the same price.  We can also do it as an outstanding RIAA phono preamp.

Regards,

Frank Van Alstine