Tekton Double Impacts

@milpai  A concern I would have regarding the use of your high gain (29 db) and very powerful Parasound A21 with the DI is that you might find yourself having to set the volume control on your TVC very close to the bottom of its range, given the very high sensitivity of the DI.

It appears that the TVC provides volume increments of 2 db, and a maximum attenuation of 54 db.  **If** the published sensitivity specs for your Quad 21l speakers (88 db/2.83 volts/1 meter/6 ohms) are accurate, with the DI you would probably be using settings that are about 5 increments below the ones you use now.  If those specs are optimistic, as is sometimes the case, figure on 6 or 7 increments below the settings you use now.

Best regards,
-- Al
 

Hi @doctorsubie 
Did you get chance to play movies using DI mains and center? What are your opinion/thoughts about  DI with matching center channel? 

Thanks

Welcome to this growing and cheerful gathering, Bill M, and congratulations on your order of the Double Impacts. Glad to hear that you are also considering the LM 508ia integrated, which I am enjoying so much that I have not been the least bit tempted to try a preamp with it. I think you'll find it is very good with the stock tubes, but shockingly good once you roll in the tubes to suit your listening preferences.

In my unit, I am using EML XLS 300B tubes, which are not exactly cheap, but are built to last and sound phenomenal in the 508. I replaced the 6SN7 tubes with Sylvania VT-231 military type tubes from the 1940s that I purchased from Brent Jessee, along with an RCA VT-229 to replace the 6SL7 stock tube. Each of these changes resulted in a very noticeable improvement in tone, texture, and layering.

I have yet to roll the 805 tubes, but will probably give the Psvane 805s a whirl later in the summer or early fall. I am so pleased with the sound at the moment, I am in no particular hurry to mess with it.

As for an earlier question pertaining to digital and/or analog, I greatly enjoy both in my system. I would say that I am fairly close to Kenny's breakdown of 70 percent digital to 30 percent analog.

Please keep us posted on your progress in building your system. If you need help finding a 508ia, let me know and I will hook you up with a dealer I found here in North Carolina. He's an incredibly nice fellow.
Chris

Bill M,

For what it may be worth, 

If you are interested in the LM 508IA and haven't done so I'd suggest either contacting either Jeff Halpern at Tone Imports (LM USA importer) to find a dealer nearest to you, or Taylor at Goldprint Audio (I believe he is who Chris is referring to in NC) for a direct purchase ; both are very good at communicating and easy to deal with. I'm in a suburb of Memphis and Jeff directed me to Taylor for my LM 518IA. 

While a different model than the 508 I will echo Chris's comments regarding rolling in NOS tubes, I did so with the 518 and it took the amp to another level. Also, I likewise don't find the need for a separate preamp with the 518.

Hi Chris,
It seems that once again our ears hear similarly. I use the EML XLS as an output tube in my amplifier. You’re using this tube as a driver tube in your amplifier and we have the same listening impressions of it.

I’m beginning to believe that driver tube selection  is as important/influential as the output power tube. You should extract many years of service from this superb tube.
Charles