Sensation Dodd Tube Buffer

OzarkTom · « **Reply #100 on:** 6 Jul 2010, 12:05 am »

Mariusz, have you tried the Gallo Strada speakers yet? These are as good as all the reviews are reporting. One of the best things about them, they will work in any size room, the smothest ribbon tweeter I have ever heard, and very quick and detailed. The ribbons disperse in 180 degrees, so no toe in is required. Oh yeah, and no crossovers. They sound like ESL's on steroids.

The Stradas work perfectly with the tube buffered Sensation, none of the tubes makes the speakers sound too bright, unless the recording is recorded that way. I finally found sone CD's that sound that way. I bought at a yard sale 40 Jazz CD's for $15, and 10 of them are old recordings where the horns sounds thin and bright. At least 30 were great, one was a Blue Note recording. I had to switch to yard sales to buy all these CD's, this Sensation amp was breaking me in that area. It is amazing how many 25-50 cent CD's people are selling. One 25 center was a Mariah Carey CD that was recorded almost as well as any of Patti Larkin's CD's. That was amazing.

tabrink · « **Reply #101 on:** 6 Jul 2010, 02:40 am »

Ozark Tom,
TomKC here expecting his Sensation with Gary's upgrades this week. I am sure I will be sending my photo studio Sensation to be upgraded when I get the first back.
Currently loving my two Virtue systems.
Nice people with innovative technology refreshed honestly better than the other guy engineering!

OzarkTom · « **Reply #102 on:** 6 Jul 2010, 02:55 am »

Quote from: tabrink on 6 Jul 2010, 02:40 am

Ozark Tom,
TomKC here expecting his Sensation with Gary's upgrades this week. I am sure I will be sending my photo studio Sensation to be upgraded when I get the first back.
Currently loving my two Virtue systems.
Nice people with innovative technology refreshed honestly better than the other guy engineering!

You in KC? If you head down to the Ozarks, stop in and see me. We will do a big tube shoot-out.

marvda1 · « **Reply #103 on:** 10 Jul 2010, 12:16 pm »

I'm asking everyone to think about me in your prayers. I will be taking my baby in today for an operation. The doctor says it's just routine, but as you know anything can happen when you go under the screwdriver and soldering iron. Dr. Dodd comes highly recommended and I'm placing my M901 in his hands. The operation will entail a Sonicap Platinum bypass on my Auricaps, too much jazz in the diet and the Dodd tube buffer. While the old ticker was still working, I need that extra boost in my life.

Let you know how it goes.
marvin
ps. Does insurance cover this? Not to worry, "Like a good neighbor SETH is there".

OzarkTom · « **Reply #104 on:** 10 Jul 2010, 12:55 pm »

Quote from: marvda1 on 10 Jul 2010, 12:16 pm

ps. Does insurance cover this?

Just watch your wallet when your baby comes back. I have never bought so many CD's so fast in my entire life. The musicality of the Dodd Buffer is that addicting.

marvda1 · « **Reply #105 on:** 10 Jul 2010, 09:37 pm »

well, she's back and I'm getting ready to start burning her in. If you are close to Gary please bring your 451/901 in and watch a genius at work. I was lost when he was just disassembling the case

Now the fun begins.

arthurs · « **Reply #106 on:** 10 Jul 2010, 09:55 pm »

Marvin - you get the e-mail I sent you?

marvda1 · « **Reply #107 on:** 10 Jul 2010, 10:42 pm »

NIGHT AND DAY

My only problem is I can't tell how much the sonicap bypass and tube buffer are doing on their own.
Prelim.
fuller sound
better attack
more detailed (bass, lower midrange, treble)
better prat
better tone
loudness seems to have increased

OzarkTom · « **Reply #108 on:** 13 Jul 2010, 04:22 am »

Tube comparison test #

STOP THE PRESS!!!!

I got all my tubes together this week and listened very closely. Here are the ones I have. GE 6201, GE 3 mica 5814 black plate, Mullard 12AX7, RCA 3 mica 5814 black plate, Tung-Sol 5814, Sylvania 12AU7, Fisher(Telefuken 12ax7), Sylvania 12ax7, GE 12ax7, Zenith `12 ax7, Amperex 7316, Ratheon 12ax7, RCA 12ax7, Sylvania 5814A, GE grey plate 2 mica 5751, and the stock JJ.

One of these stands out better than the rest, and it is by a clear margin.. Does anybody want to take a guess?

I will post the winner tonight about 9pm CDT.

wsturner · « **Reply #109 on:** 13 Jul 2010, 05:14 am »

Quote from: OzarkTom on 13 Jul 2010, 04:22 am

One of these stands out better than the rest, and it is by a clear margin.. Does anybody want to take a guess?

The stock JJ?

marvda1 · « **Reply #110 on:** 13 Jul 2010, 06:03 am »

The Amperex 7316?

dangerbird · « **Reply #111 on:** 13 Jul 2010, 11:02 am »

GE 3 mica 5814

marvda1 · « **Reply #112 on:** 13 Jul 2010, 02:24 pm »

does the winner get the tube?

ebag4 · « **Reply #113 on:** 13 Jul 2010, 02:42 pm »

GE grey plate 2 mica 5751

This is what I am running in my DIY Dodd Buffer now, sounds good to me but I would like to know where it fell in rank vs the other tubes.

Best,
Ed

correction, mine may be a black plate.

OzarkTom · « **Reply #114 on:** 14 Jul 2010, 02:23 am »

And the winner is.........Ed.

Er, I mean the GE 5751 two mica grey plate.

It has the most of everything. Most soundstage width, most soundstage depth, most soundstage height, best vocals, best tonal quality, best focus, best clarity, most detail, most hall ambience, what else is there? You just here more info which leads to more pleasure. In fact, this tube shows me the 12ax7 and 12ay7 by anybody else sounds hazy by comparison. The 5751 is supreme.

If you really wanted to do some serious tube rolling, just stay with the 5751 family of tubes. Don't bother with anything else. The only problem is the price. Some tube stores are asking up to $200 for the GE 3-mica black plates. After googling these tubes, it is said that Stevie Ray Vaughn used it in his tube amp, so now a lot of guitarists are now buying these tubes and saying they are the best sounding with their guitars.

Good news, there were not a lot of companies that made these back then. RCA, GE, Raytheon, and Sylvania were the main US companies, and Siemans was the only Euro company that was authorized to make these. You will not have to buy a lot of brands.

Second place did go to the Amperex 7316. I am still trying to figure out the hype on the Mullard and Telefukens.

Now do I whole-heatedly recommend this tube? No I don't.

It is way too microphonic when you raise the volume up or down on the Sensation. It is the most noisy of all. I have a couple of the triple micas coming in this week, I will see if those take care of the micro-phonic problems. Man, if these sound even better, look out.

Anybody here needs a bunch of of my other tubes?

ebag4 · « **Reply #115 on:** 14 Jul 2010, 03:06 am »

Thanks for the comparison and the followup info OT, much appreciated.

BTW,
I don't find my 5751 microphonic at all and my buffer is sitting about 1.5' behnd my V-1s on a board on the floor. That puts it 1.5' from a pair of servo subs.

Best,
Ed

OzarkTom · « **Reply #116 on:** 14 Jul 2010, 11:58 am »

Quote from: ebag4 on 14 Jul 2010, 03:06 am

BTW,
I don't find my 5751 microphonic at all and my buffer is sitting about 1.5' behnd my V-1s on a board on the floor. That puts it 1.5' from a pair of servo subs.

Best,
Ed

Do you get any noise when you adjust the volune up or down? If not, maybe I have a small issue with my Sensation.

ebag4 · « **Reply #117 on:** 14 Jul 2010, 12:10 pm »

Quote from: OzarkTom on 14 Jul 2010, 11:58 am

Do you get any noise when you adjust the volune up or down? If not, maybe I have a small issue with my Sensation.

Actually yes, a little white noise while the pot is turning, but no other time. I would think a microphonic tube would be susceptable to footfalls and other types of viabration as well, I don't hear that.

Best,
Ed

OzarkTom · « **Reply #118 on:** 14 Jul 2010, 12:36 pm »

Quote from: ebag4 on 14 Jul 2010, 12:10 pm

Actually yes, a little white noise while the pot is turning, but no other time. I would think a microphonic tube would be susceptable to footfalls and other types of viabration as well, I don't hear that.

Best,
Ed

All I get is the white noise also, I guess that is what I am referring to. The GE 5751 is the loudest I have tested in ny system.

momini1 · « **Reply #119 on:** 14 Jul 2010, 12:55 pm »

Doesn't surprise me. I also have an Onix Sp3 and lots of owners of this amp use the 5751 instead of the 12ax7 because the Onix has an stepped volume control and we need a tube with a little less gain for low volume listening. The byproduct is that you get a tube that is very, very quiet and may actually be better than the majority of the 12ax7s out there. Never had any problems with microphonics with the tube - but then the Onix is so heavy it would probably take a 7.1 on the Richter scale to budge it.

I am using a Sylvania JAN 5751 in my 901 right now, although I think all the tubes I have tried so far - the JJ it comes with, RCA cleartop, Brimar 13d5, Telefunken ecc83, Matsushita 12ax7 - all sound pretty much the same to me. Slight differences in soundstage, some changes in tonal balance, but all very good. Like some other owners, I am still breaking the amp in since the mods were made, and it is hard to sort out whether the minor changes I hear are the caps breaking in, the tubes or just the attention deficits I tend to have during the day.

I have bought quite a few tubes from Dennis Boyle at Chimera Labs, and I can say his prices are fair, his selection is good and his service and advice are excellent - beats buying off ebay from someone you don't know.