Rectifier tube for Dynaco ST-70

[NOSValves]

Jazman,

Marvel, Tony,

Thank you. You both have pointed to simple information I was attempting to convey

Where were you trying to convey anything but your opinion please show me ?? Besides both of these posters were agreeing with me !! Man you are blind

[ben.]

Will wonders never cease?! Ryan sticking up for Craig! It's great to see bygones..., but I keep looking up in the sky for fish to fall and for the Erie Canal to flow red!

[NOSValves]

Kind of strange isn't it !

[bkrop]

Hey H.H.Scott expert/ecc83/350 Nova SS/Ryan: Way cool to bury the hatchet and jump in when you didn't have to!

[jazman]

Ryan,

No, they don't sound the same. Maybe in that ST70 it does not matter, and I will grant that since I have not heard it with the two tubes. In my amps you CAN hear the difference. Maybe I'll purchase a current set of them and relisten, but I don't think that will change. If you have hardware capable of resolving the differences, this is more than a matter of performance specs. I'm glad Dean recently found the Cary pre is capable of revealing different sonic characteristics of different tubes. Revealing hardware can reveal sonic differences.

Craig,

Again you're full of ****. You're one big bull**** artist if there ever was one. You still wish to put a tag on me? I suggest you kiss me where the sun does not shine. You and your business will self destruct on top of their own pile of crap and lack of merit if given enough time.

Klipsch out.

[NOSValves]

Jazzman,

Earlier you said

If you wish to attempt to wage a continuing war of words with me, have at it by merely sending me an email and I will happily oblidge, but be forewarned that you are overmatched. Know your limitations!

Now you come back with <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

Again you're full of ****. You're one big bull**** artist if there ever was one. You still wish to put a tag on me? I suggest you kiss me where the sun does not shine. You and your business will self destruct on top of their own pile of crap and lack of merit if given enough time.

Youre really going to have to do way better then that to achieve your Superior status you self proclaimed your self to be!! Your not impressing me at all.

I run my business in a no bullsh!t down to earth fashion and my customer so far seem to like it and the amount of work I'm getting sure seems to say I'm doing something right !

Later

[Deang]

"Thank you. You both have pointed to simple information I was attempting to convey before Craig entered into his name calling and attempts to degrade equipment he knows little to nothing about."

Actually Edmond, it was you who leveled the first slam - "Craig tends to discredit anything that involves a cost greater than he's willing to pay." As far as I know, Craig pretty much reserves this attitude for cable debates. I don't think this statement is fair to Craig. Now, Craig did follow up by calling you an "audiophile", which could be construed as derogatory.

"I won't dignify your idiotic statement about Moondogs with a rebuttal. It's your standard, expected, lack of class to knock what you don't know about. All of a sudden you're "Mr. Tube amp Expert" ... I suggest you go pick on someone who's mind is as small as yours, since you seem neither prepared, nor capable, of discussing the merits of the issue at hand ... you remind me more of a tire changer claiming to have the knowledge of the engineers who designed the tire. You make grand attempts to be such a large fish in the little pond of this forum ... you're no circuit designer of anything ... you're full of ****. You're one big bull**** artist if there ever was one ... you and your business will self destruct on top of their own pile of crap and lack of merit if given enough time."

I find most of this out of place and rather uncharacteristic of you Edmond.

When did Craig ever claim to be a circuit designer? He claims to restore vintage equipment, which apparently he does quite well. He may have to peck at his keyboad with 10 thumbs, but he obviously has the aptitude and skill-sets necessary to bring most of the old stuff back to life. He is being mentored by one of the best minds to ever inhabit this forum -- and I'm quite sure Craig knows what he is talking about as far as how tubes relate to various parts of the circuit(s).

Craig's response was in the context of a Dynaco ST-70, and other vintage gear utilizing push-pull pentode and pentode/ultra-linear circuits. Edmond, your response was in the context of your particular experiences.

I had extensive conversation with Craig tonight, and as much as we have in common with music types and listening habits -- even we don't always come to agreement. This is one of those times. However, my experience is with rectifying tubes in preamps (both my now sold AE-3 DJH, and present Cary SLP-90/4. Both of these preamps use the EZ-81 -- and I hear a significant difference when I roll these tubes.

You guys are listening to something I haven't experienced yet -- the rectifier in the amplifier. I do find it interesting that he admits a diode will change the sound, but that different brand rectifying tubes don't make much difference. Since both the diode in solid state rectification, and the tubes in tube rectification are both doing the same thing (changing AC to DC) -- , why should the diode sound different than the tube? At any rate, I think it makes a difference because I can hear it -- but only as it relates to my system.

I have no problem believing there is no discernible audible difference in these tubes in the circuit originally being discussed, or many other circuits that haven't been discussed. I also have no problem believing there are very big differences in the sound when these tubes are rolled in SET amps, and again -- other amps that haven't been discussed.

We all need to be very careful in make ANY absolute statements. Haven't we learned anything in the last two years? We are all working from a different frame of reference -- our listening rooms, choice of recordings, and synergism between components. Basically, the only thing I've learned is that most changes are completely unpredictable.

As a side note, Craig and myself do not habitually listen to music at 110db. We both listen around 90-95db.

Personally, I'm worried about Craig and Edmond both. Craig thinks my music sucks, which means he will soon gravitate towards elavator and little girl with guitar music, and Edmond's getting cranky as hell and doesn't like it when I use my charge card while owing him money.

[mike stehr]

I've noticed differences rolling tubes in my little Magnavox SE 6BQ5 amp.

The driver tube made the most difference.

Between a 6EU7 Mullard and RCA I prefer the Mullard.

But the RCA 6EU7's I have are not as strong, and that could be a reason.

Rolling output tubes, Mullard El-84 and Wells&Gardener branded 6BQ5 black plates have a nice sweet sound to them.

Pretty comparable, but I'm kinda partial the black plates.

I like the Sovtek military EL-84 monsters as well, no sweet sound, just neutral in a way with tad bit of grit.

Good tubes for Metal.

The old RCA 6BQ5's seem to have a good neutral sound without the grit of the Sovtek's and a tad of sweetness.

I need to get more of these.

Never have rolled the rectifier tube, I figured there was so much praise for the Mullard EZ-81 that it was fine for the job. I do have some National brand bootleg whatever Russian EZ-81's I could try.

Mullard EZ-81 is a good rectifier tube, IMO.

But I could be completely insane, so these opinions should be discredited.

[NOSValves]

Dean,

You guys are listening to something I haven't experienced yet -- the rectifier in the amplifier. I do find it interesting that he admits a diode will change the sound, but that different brand rectifying tubes don't make much difference. Since both the diode in solid state rectification, and the tubes in tube rectification are both doing the same thing (only changing DC to AC) -- , why should the diode sound different than the tube? At any rate, I think it makes a difference because I can hear it -- but only as it relates to my system.

The reason I advise against installing a SS Diode in a amp that is not designed for it is pretty simple. It takes some serious changes throughout the amp to allow for it safely to be used and even then from what I have heard it still leaves a SS signature to the sound because there isn't room to install enough filtering. Its all about filtering, tube rectifiers do a cleaner job of turning AC into DC. Look what your amps require on the first B+ compared to say my ST-70 yours has 500UF mine has 100UF which is over kill to say the least on mine.

The designer of the SDS cap board which is designed for the Dynaco's has it setup for Diodes or tube rectification. You know what he recommends .. you bet ya .. stay with the tube rectifier the sound will be cleaner because even with his board he can't stuff enough filtration on there to clean up the SS diode. Also when replacing a 5AR4 there is a slow start feature you will lose that really saves on tube life.

Craig

[Deang]

That's interesting Craig, I've been wondering for a while how that worked. So this ties in with what we were talking about last night on the phone.

Do you you think the solid state signature on solid state rectified/diode tube amps is related to some AC ripple riding along with the outputted DC?

Please check out my question in the thread I started below about stereo amps being converted to mono amps. Do you have any idea how this is done? Are the outputs just bridged together?

[Deang]

Found this:

Kind of interesting.

http://db.audioasylum.com/cgi/m.pl?forum=tubes&n=102301&highlight=converting+stereo&r=&session=

[Deang]

"I like SS diodes, especially for alternative music, but they are hard on the power tubes and power supply components. And without the addition of a stand-by circuit, their "instant-on" feature tends to kill the power supply electrolytics and strips the output tube cathodes."

Somewhat curious information considering the reputation for reliability companies like Sonic Frontiers and Quicksilver have -- which both utilize the diodes in their products.

I can definitely understand the thing with the lower tube life though.

The solid state signature bit with diodes is somewhat confusing to me, especially considering how 'tubey' my Quicksilvers sound.

[NOSValves]

Dean,

but with these companies designing brand new products they have the advantage to design the safety devices and filtering into there design from the start. Us vintage guys do not have that luxury we have to try to find room for all the added components and Electrolytic values. I'm not all that up on Solid state devices but I know to do it properly major changes to the circuit have to take place. Like Ryan said its just not worth it.

To me a tube amp should have the absolute minimum SS devices possible or before you know what do you have ...... a SS amp.

I bet your silvers sound real tubey playing Chevelle !!

Craig

[Deang]

"I bet your silvers sound real tubey playing Chevelle !!"

Oh heck yeah! Gorgeous, fat, bold, ferocious -- the nice deep brown sound you get from the best sounding guitar tube amps. The sound I've been chasing from the beginning.

I was asking my daughter what kind of music she's been listening to. She lists off about 5 bands who's CD's I just happen to have stacked in front of my system right now.

"Wanna hear the system?"

"Sure."

I took her up and pointed to the chair.

"Do you just want to listen to it, or do you want to hear it? How loud do you want it?"

"Oh, I like it pretty loud. That's kind of what I'm used too."

What's great is being able to put the juice to the RF-7's without having the ears get pinned back.

I might force myself to try Class A push-pull again someday -- but only if I don't have to sell off the Quicksilvers first. I would really want to do a straight on comparison.