What Mods for a pre/pro to become a good preamp?


Many components are plugged into the pre/pro unit that use the Digital RCA. I would like to retain the bass management and speaker distances etc. of the pre/pro, yet get the fidelity of a good preamp when using my PVR, Satellite, and especially DVD.

I understand that a high quality power supply or addition of a second high quality power supply helps reduce jitter. What other items should be important to improve the sound quality? Please be as descriptive as possible.

I am using all available analog pass through. I am hoping to improve the outcome for components using Digital RCA and AES-EBU. I am using a Lexicon MC-12B, version 3 with the microphones.

I have a service manual. What else would I need?
yada
You need a pre amp, the Lexicon is a pretty good AV processor but, even the best AV computers seldom sound as good as even some of the very least expensive preamps.
Find a pre amp that you like that has a AV bypass and use your Lexicon for movies and multi channel music and the pre amp for everything else. You wont need the bass management for two channel as, by definition, you aren't using the sub you have plugged into your LFE channel of your Lexicon.
Agaffer, perhaps you are correct as a general rule of thumb. But then there are always excepts to those rules. I own a Primare P30 pre/pro and a Chapter Audio Pre-amp which retails for almost 3 times the price of the P30.

I've also owned and A/B compared the P30 to the Pass Labs X2.5 and X-1 preamps, as well as a fully loaded Placette Active Linestage. In addition, I borrowed a Conrad-Johnson PV14, an Electrocompaniet, and an Ayre k3-x preamp in order to perform some A/B comparisons to the P30.

The Chapter Preface is the pretty clear leader over all the others and the best preamp I've heard to date. But the very highly rated Pass Labs pre-amps just barely surpass the sonics of P30 and the ergonomics of the P30 are better than the Pass Labs units.

As good as the Placette was in the highs, it simply could not provide a balanced or proper weighting in the lower regions like the P30 via it's XLR connections.

The CJ, Electrocompaniet, and highly rated Ayre weren't even in the same league as the P30.

Primare is a little known Swedish company with a music first and minimalist approach. And the P30 provides a 100% TRUE analog processing when in by-pass mode.

Of course there are compromises with the P30 just as with virtually every other product. But the P30's sonic attributes across the frequency spectrum are quite competitive with any one of the preamps I mentioned above and even superior to some of those same.

Yada, I'm not familiar with the sonics of the Lexicon, but I would recommend your considering the following mods to maximize your performance:

1. Disconnect the grounds on all components except for your preamp.

2. Install your preamp (and your other components) on their own dedicated circuits/lines.

3. Install Hubbell cryo-dipped wall outlets, IECs, and plugs. I've only tried one such IEC and the improvements were quite surprising.

4. Consider switching over to XLR for potentially better dynamics.

5. Install Star Sound's Audio Points underneath to transfer vibrations away from the preamp.

6. Install the pre/pro and your other components in a racking system that will follow the same principles as the Audio Points. In other words, coupling or mechanical transfer of air-borne vibrations and resonance to ground.

7. Purchase a Foundation Research LC-1 in-line power conditioner(which is dedicated to one component). Better yet, purchase one for every component.

8. If configuration settings allow, shut down all the Lexicon's text displays and digital processing and set all settings possible to by-pass mode if it provides 100% TRUE analog processing. I use the word TRUE because some to many pre/pro's still convert the signal to digital and then back to analog even when they advertise 100% analog processing. The less the Lexicon does, the less electrical noise the better the potential for sonic improvements.

Hope this helps,

-IMO
Hi Stehno:

Thanks a lot for your input. I am really happy to hear from someone who has contributed a lot to the forums over the years.

I did not do item 1 above, but I really worked on the other items.

I use eight separate 30 amp circuits with either Porter ports or Alan Kaftons' receptacles. They Lexicon uses a King Cobra v2 to its own SA Linestage with Elrod sig 3 to the wall. I use Quattro fil and Valhalla xlr to the amps. I would try the Starsound, but I am already buried in several layers of Aurios Pros, (for the component stand and under the Lexicon). The Lexicon currently sits on an Ultra, then Aurios Pros, then a Svelte and on top of the svelte is a Stillpoints. It barely fiits in the 19" or so I have for the shelf.

To rephrase my question, when I have to use the Lexicon for my DVD, Satellite and soon to arrive HDTV recorder using Digital RCA, what would you consider having done to the Lexicon to become more like a preamp in its sonic attributes yet still retain the bass management and speaker distances etc.

When I am in bypass mode, I really like the sonics of Dan Wrights CDP or something of that caliber. I was hoping to get the Lexicon to emulate that when forced to use other components using digital ins.
"Agaffer, perhaps you are correct as a general rule of thumb. But then there are always excepts to those rules. I own a Primare P30 pre/pro"

I don't get your point. According to the Primare Audio website, the P30 is a pre amp, not a AV processor. I'm sure it is a good pre amp and were Yada to use it in conjunction with his Lexicon I am sure that it would be a big improvement in sound quality.
However, I was thinking about improving the music side of his listening. Rereading his post I see that isn't what he is looking for. He wants to mod his AV processor to improve on it .
Agaffer, the P30 is the previous model of Primare's SP31.7 (or something like that) current model pre/pro. They've done some number changing on their models. You're thinking of the new Pre30 which is Primare's 2-channel preamp.

The Primare P30 really, really is a pre/pro. Just ask me!!! :) Although I used it only as a 2-channel preamp.

-IMO
Yada, you might still consider setting aside all of the decoupling (dampening and isolation) paraphinalia that you've invested in and try the less expensive coupling methodology.

If, and I believe it is so, the coupling methodology (using Star Sound's Audio Points and a racking system like the Sistrum) provides better sonics, there are plenty of people who would gobble up all of your decoupling products. Not only may your system sound better but it may also look better with less clutter and may even put a little extra $$ in your pocket.

Also, have you considered converting one or more of your components to 240 volts aka balanced power (requires running 240 volt lines from your service panel)? This should provide a more pristine and effortless presentation.

-IMO
Yada:

My guess is that the sonics of the EAD Theatermaster 8800 pro would be preferable to the Lexicon in light of your tastes and equipment. While I protect my 2 channel path entirely from running through a Pre/Pro....I can honestly say that EAD is the first Pre/Pro i've heard that has led me to consider simplifiying my setup by allowing my 2 channel path through it. Incidentally, I've had both Lexicon and EAD and find the sonics of EAD FAR superior. Several audiophiles that I respect have agreed with this.

Regards,
Harry