2. amps-preamps
  3. 1135309079

Newbie Tubie just wants insight and direction....

Hi All and Happy Holidays!
I recently acquired a used Antique Sound Lab 1001dt, it's not the newest version with remote but it does have the built-in bias meter (thank God for this!).

I've recently come over from the SS camp owning a B&K AVR 307. What I'm noticing, and this is only 2 ch vs. 2 ch for the B&K vs. the ASL, is that for HT/movies, I don't get a good center image. I've checked all the settings on the 999es to make sure that it's in downmix 2ch. mode/analog only out so basically I'm only swapping out the amplifiers.

I get a great center image with the B&K but with the ASL the sound seems to be coming from just left and right...not "transparent" if that's the right term. Voices just don't jump out from the middle of the screen as it does with the B&K.

Now, as far as music goes, it's a totally different story, it's HUGE and lucious, velvety and "easy" but there are still some times when I feel that the music doesn't have the proper staging or imaging conjuring up one large ensemble out in front of me or to the center.

Is this just an "experience" of moving from SS to Tube gear or do you think there may be other issues to deal with.

For all purposes I've included all equipment relative to this question below.

Thank you in advance for any insight or advice, tips or tricks...again, Happy Holidays!

Your new tube rig advocate!

Current equipment:
Marantz 63se
Sony 999ES for SACD and HT duties
ASL 1001dt integrated (JJ Tesla kt88's stock 12au7's)
Paradigm Reference Studio 20's V.2's
Silent Audio Apollo C's (the silver ones, can't remember whether these are the C's or the A's)
Signal Cable Bi-wire
Signal Power Cord

I have other equipment but I'll focus on these for now since my question really pertains to 2 channel.
auditude
auditude OP
10 posts
 
Just a short follow up. I'm going to blame most of the issue on the source player. I had an older Sony 755 SACD/DVD player pulling ht duty and had the marantz for redbook. The sound was very "thin" and when I swapped in my 999es it has improved.

I still don't believe it projects the "best" center for dialogue but I'm still getting used to the difference in sound from SS to Tube gear.

Music is still glorious but I want to make my speakers more transparent.

On some material they just vanish and then on others, and this may be due to the recording, there are still traces of "speakers" being present.

I'm chasing the unicorn again guys and gals but at least I feel as if I'm gaining!

Thanks for the suggestions!

BTW, polarity/phase was fine on both amp and speaker end.
bignerd100
515 posts
 
Having "correct" polarity coming off of a tube amp requires YOU inverting the polarity (in other words, either on the amplifier OR on the speaker you have to have + on the - and - on the +).

If all of your plusses and minusses and red and black match up you are out of phase on tube gear. THere has to be an inversion of polarity somewhere in the chain.

Good luck!
rwbadley's avatar
rwbadley
143 posts
 
""Having "correct" polarity coming off of a tube amp requires YOU inverting the polarity (in other words, either on the amplifier OR on the speaker you have to have + on the - and - on the +).""

I have not heard this, care to elaborate? Or is this a tongue-in-cheek statement?
clio09
3,362 posts
 
My preamp inverts polarity and as such I swap the speaker connections on the amp side. However, polarity can be inverted on front end source equipment (like DACs), amps, and from speaker cross overs as well (actually experienced the last one unexpectedly while swapping a woofer out). Only way to tell is by test. For my analog front end (TT and phono stage) I used the HiFi news test record and the system tested fine. I imagine there is a test CD that can do this as well for digital front end, but I haven't located one. Maybe someone can recommend one.
bignerd100
515 posts
 
Rwbadley,
No tongue-in-cheek. Most tube amps do not invert the phase of the output signal in order to simplify the circuit. The positive and negative taps are correctly positive and negative but the signal is 180 degrees out of phase. THe easiest and most efficacious way to get things in line is to swap the +/- at either speaker or amp end. If your preamp has a phase inversion feature (as Clio09's does) you can use that instead.

The manual for Auditude's ASL should state if this is the case with his particular amp. If it doesn't then I guess that most flawed of instruments must be employed,... the human ear.

Good luck!
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