Great tube rolling suggestion!

OgOgilby · « **Reply #80 on:** 13 Nov 2009, 07:52 pm »

Quote from: oneinthepipe on 13 Nov 2009, 03:05 am

I can't do a side-by-side comparison because I don't have two T8 preamps. Nonetheless, OgOgilby, who lives nearby, has a T8 DAC, and maybe we can subjectively compare two dissimilarly-tubed T8 DACs side-by-side.

Sounds good to me

Dan Kolton · « **Reply #81 on:** 13 Nov 2009, 10:11 pm »

Just ordered that earlier mentioned pair of Mazdas from an AC member. Which should I try them in; my Pre or my DAC?

mark funk · « **Reply #82 on:** 13 Nov 2009, 10:43 pm »

I would put them in the preamp, when I use to roll tubes I could change the sound more by rolling tubes in the pre then in the T-R DAC. Maybe thats because my T-5 is all tube and the DAC is MOSFET/Valve and I think rolling tubes in that does not change the sound as much as the all tube stuff. Have fun rolling

rlee8394 · « **Reply #83 on:** 13 Nov 2009, 11:34 pm »

OITP,

Quote

I can't do a side-by-side comparison because I don't have two T8 preamps.

You could put one 6CG7 in one channel, and the 6N1P in the other. Playback in mono and use the balance control to switch between channels for comparison. I believe Frank uses this method to compare changes in product, although he places the speakers next to each other so the sound emanates from basically the same space.

Ron

oneinthepipe · « **Reply #84 on:** 14 Nov 2009, 12:44 am »

Quote from: martyo on 13 Nov 2009, 10:06 am

Which amp were you using?

Macintosh/AIFF -> Insight DAC -> T8 preamp -> Insight 440

Art_Chicago · « **Reply #85 on:** 14 Nov 2009, 03:27 am »

I just put the EH tubes in the T-8 preamp and I think it is definitely worth upgrading, no doubt. The background is lower; the saxophone on Take Five is smother/richer/juicer. The acoustic guitar by Nils Lofgren (Salk demo) sounds more detailed with richer timbre and more "twangy" indeed! I did not notice any drop in the bass region using Salk's demo track 1 and 2. Will put some heavy stuff tomorrow.
martyo, thanks for the pics of the T-8, mine looks the same now

oneinthepipe · « **Reply #86 on:** 14 Nov 2009, 04:39 am »

Quote from: rlee8394 on 13 Nov 2009, 11:34 pm

OITP,
Quote
I can't do a side-by-side comparison because I don't have two T8 preamps.

You could put one 6CG7 in one channel, and the 6N1P in the other. Playback in mono and use the balance control to switch between channels for comparison. I believe Frank uses this method to compare changes in product, although he places the speakers next to each other so the sound emanates from basically the same space.

Ron

Great advice, Ron. I will try that next week when I have more time.

martyo · « **Reply #87 on:** 14 Nov 2009, 11:45 am »

My wife is working today.....going to swap out the tubes, NOS to preamp, will report back....

cminer · « **Reply #88 on:** 14 Nov 2009, 05:05 pm »

I think I may have found an easier solution than replacing the tube sockets.

I went down to the local home improvement store and picked up some 1/2 inch long 6-32 machine screws and some 6-32 nuts. I put the screws up through the bottom of the chassis and put two nuts on the other side as spacers. Then I just dropped the board down over the screws and put another nut on top to hold it in place.

Much easier than replacing the socket and it leaves enough room under the board so it doesn't squish the wires running under it.

By the way, my impression of the new tubes is pretty much what others have said. It seems to bring me a step or two closer to the music. In fact my non-audiophile wife said it sounded more 'live' to her. Unlike others I haven't noticed any drop in the bass.

Well worth the price of admission.

Curt

Art_Chicago · « **Reply #89 on:** 14 Nov 2009, 06:03 pm »

Quote from: cminer on 14 Nov 2009, 05:05 pm

I think I may have found an easier solution than replacing the tube sockets.

I went down to the local home improvement store and picked up some 1/2 inch long 6-32 machine screws and some 6-32 nuts. I put the screws up through the bottom of the chassis and put two nuts on the other side as spacers. Then I just dropped the board down over the screws and put another nut on top to hold it in place.

Much easier than replacing the socket and it leaves enough room under the board so it doesn't squish the wires running under it.

By the way, my impression of the new tubes is pretty much what others have said. It seems to bring me a step or two closer to the music. In fact my non-audiophile wife said it sounded more 'live' to her. Unlike others I haven't noticed any drop in the bass.

Well worth the price of admission.

Curt

so, you removed the spacers under the board and used these screws +nuts instead? interesting...
btw, it makes 3 (+martyo) of us that like the bass with the new tubes!

OgOgilby · « **Reply #90 on:** 17 Nov 2009, 04:17 pm »

Quote from: cminer on 14 Nov 2009, 05:05 pm

By the way, my impression of the new tubes is pretty much what others have said. It seems to bring me a step or two closer to the music. In fact my non-audiophile wife said it sounded more 'live' to her. Unlike others I haven't noticed any drop in the bass.

Curt

Oneinthepipe mentioned that the low end might not be as tight as the Insight SL's low end. Did you notice any difference in the tightness of the bass?

cminer · « **Reply #91 on:** 17 Nov 2009, 08:08 pm »

With my Ultra EC, at first I thought I heard a little less bass, but I think that must have been because that's what I expected based on what I'd read here. After swapping the tubes back and forth several times I decided there really wasn't enough difference to call it. I listened to "Flamenco Sketches" the other night with all the lights turned off and that bass sounded like it was right there in the room with me.

Something I noticed right away, and what really sold me on the new tubes was drums. They seem to have a lot more snap now. I guess that falls under 'transient response.'

Curt

cminer · « **Reply #92 on:** 18 Nov 2009, 01:43 am »

I just got home from work and tried another experiment. On a recording of Saturn from 'the Planets,' right at the 8 minutes mark this huge organ note suddenly appears out of nowhere, about 45 Hz or so. It rattled the windows and almost drove me out of the room.

No, I haven't noticed any bass problems.

Curt

JerryM · « **Reply #93 on:** 18 Nov 2009, 02:45 am »

Frank,

Do you plan on selling 6CG7 tubes with your 'tested in circuit' service?

Mountain-ear · « **Reply #94 on:** 3 Dec 2009, 04:33 am »

Thanks for a great suggestion, Frank. And thanks to OITP for sharing his information on the short Mazda 6CG7 tubes. I got mine from Ned at TubeZone.net and they fit my T-8 perfectly. It took a few minutes for everything to get warmed up, but I'm liking them better all the time. Bass was actually a bit stronger than the previous 6N1P tubes -- both to my ears and to my Phonic PAA2 real-time analyzer. I'm still getting used to the high end (seemed a little harsh at first but mellowing out now). Stage depth and imaging seem better -- to my 51 year old ears anyway -- but YMMV.

Steve

martyo · « **Reply #95 on:** 3 Dec 2009, 09:25 am »

Jerry, from earlier in the thread-

Quote from: avahifi on 6 Nov 2009, 03:16 pm

mathgeek97, sure, if you supply the necessary Cinch low profile sockets we will build either an Ultra or T8 preamp equipped to handle the 6CG7 tubes directly. However, we are not stocking these tubes at this time so you will need to supply your own tubes. The unit will come with 6N1P tubes which you can swap in or out as you choose.

No extra charge for this service of course.

Regards,

Frank Van Alstine

JerryM · « **Reply #96 on:** 17 Dec 2009, 03:09 am »

So, for the last two weeks I have been burning in a pair of perfectly matched Mazda/Brimar 6CG7 valves from Kevin over at Upscale Audio. These are in the T8 preamp. I did not roll different tubes into the T8 DAC (yet). Last night and tonight I have sat and enjoyed some careful listening. The differences between these valves and the 6N1Ps are pretty apparent.

First, I don't really notice any more bass than before. The bass is tighter; more defined; punchier. The top end is remarkably the same as before. The mids have more definition and texture.

To me, the biggest difference is in the soundstage. It's pretty amazing, and worth the price of admission in and of itself. Instruments and voices are much more focused, and in tighter individual spaces. The height and width of the soundstage is greatly improved, and it didn't need to be improved one little bit. It is, though. The depth of the soundstage is what gets me the most. It is like I can 'see' past the front of the stage, and listen exclusively to the back of it. Perfectly clearly. The depth is weird, as it is deeper than the speakers could possibly be from the wall. While this aspect was really very nice before, it is remarkable now.

The change to the soundstage has made the bass more real; more taught. The highs, while not seemingly affected by the 6CG7s, sound better as they are better placed, and sound more like 'live' to me due to where I hear it coming from now. I have always enjoyed closing my eyes and listening to the whole system just disappear. I open my eyes and kind of chuckle to myself where the speakers are in relation to what I was just hearing. For the past two nights I have sat here with my eyes open, doing the same thing. It's pretty cool. It seems like I can reach through the center of the soundstage, almost into a triangle of space, and touch the drummer; or bassist; or into a grand piano to feel the strings.

Lastly, is there a little less gain in the preamp? I definitely have a few more clicks of upward rotation on the volume knob before I start to worry about the neighbors. I don't know if it's a gain thing, or if some strange harmonic is now missing. I don't have an SPL meter at the ready, so I can't comment on a genuine reading. I can certainly turn it up quite a bit more now, though.

Eventually, I will roll the 6N1Ps back in and give a good hard listen to those being back. But for now, the 6CG7 valves have made a marked improvement, in a very appealing way.

Thanks, Frank.

Have fun.
Jerry

martyo · « **Reply #97 on:** 17 Dec 2009, 09:45 am »

Thanks Brian and Jerry. I didn't know those Mazdas were Brimars! With "12" signal tubes, I love the midrange and front to back of the Brimars I've listened to(thanks mark).

Yes, the depth, front to back, and the new, more focused soundstage with that front to back clarity. aa

trebejo · « **Reply #98 on:** 17 Dec 2009, 10:30 pm »

[edited to avoid stepping on toes, which is not my desire in the least. Wayner's reply below applies to that version, I assume.]

I found a list of tube options somewhere, for another preamp, which gave the following gain specs if using the tubes discussed here.

The 6n1p got 18db, and the 6CG7 got 16db. So, in that preamp, the switch brings things down by 2db.

I don't know what that implies (in db, specially!) for the analogous swap in the van Alstine preamp or DAC.

You can pm me if you wish to be directed to the specific web site.

Wayner · « **Reply #99 on:** 17 Dec 2009, 10:45 pm »

Perhaps the best place to post a topic like this is NOT on the manufacturer's circle.

Wayner