I'm looking for info about tube amps (1 Viewer)

[John Morris]

How do you do that? Do you get someone else to switch the tubes while you're not looking?

Yep! My wife is now an expert tube changer, and yet, she is so unknowledgable about the tubes, she wouldn't know which tube is which, even if she cared a bit about all of this. She does know though(as a result of some careful training), how to extract and insert a tube without bending the pins.
Next up, headphone cables... I think I'm gonna try the new Cardas cable and/or the Clou Red Cable for my Senn HD-600s. Of course, I'm getting them from a retailer who offers a 30 day money back guarantee.

 

[Saurav]

John, that's cool. My wife enjoys my hobby, but I don't think I could convince her to switch tubes for me. She's intimidated enough by all the power switches. I will admit, my DIY stuff doesn't look very user-friendly, and when you throw in instructions like "make sure you wait at least 30 seconds after turning this on, or you'll blow this", most normal people would stay away
Ken, have you seen prices on ST-70s on eBay recently? I've seen a few with shiny chrome and premium tubes go for $700. I've seen rusty "don't know if it works did not plug it in" ones go for $300. IMO, there are much cheaper options out there - Eico, Scott, Fisher, etc. Of course, that also brings up teh whole issue of vintage gear - given my experience with it, I wouldn't really recommend it for someone starting with tubes. The Jolida/ASL kind of gear is much more plug-and-play. Once someone gets used to what's involved, they can then enjoy the Dynacos.
Just IMO, of course.

 

[Jeremy Hegna]

"As for their sound... the top two or three systems I've heard have been based around tube amps."

Saurav,

I agree 100%. I was visiting Hawaii this past winter and stopped by a local audio shop. It was a bit cluttered in the front but the owner took me into his "back room." He had Avantaguarde (sp?) Trios powered by 6 60watt tube amps.

UNREAL!!!! It took him 7 years to put it all together, but the sound was phenomenal.

Jeremy

 

[Saurav]

I heard a system with Oris horns, the owner used to have Avantgarde (sp? I'm not sure) Duos, I think, before the Oris. Going by his posts on some forums, the two are comparable in quality, different only in presentation. So, I can imagine what your experience would have been like. For me, it was the first audio related experience I've had that could come close to being described as life-changing It certainly changed a lot of my ideas about what is obvious and taken for granted. Of course, this does not include live performances, which is why I said 'audio related', not 'music related'.

 

[John Morris]

John, that's cool. My wife enjoys my hobby, but I don't think I could convince her to switch tubes for me.

Saurav: It took some convincing to get her to wear the white glove though... the first really hot-tube-to-finger contact convinced her.

 

[Ken Situ]

I have no idea the Dynaco's are costing that much on ebay now. I got a few Mark III's and Mark IV's, which I paid roughtly $100 CAD (about $66 US) each, and a PAS III for $45 CAD, and they just won't quick working.

 

[Saurav]

I'm pretty sure Mk IIIs and IVs cost a fair amount more than that now. I think Dynaco's are overpriced these days, from what I've read about how they compared to some of the other vintage manufacturers. I tried out an Eico HF-81 in my system for a couple of weeks, and that sounded really good. Those can be had for much cheaper than an ST-70, and some people believe the HF-81 was one of the best amps from that era (and probably also one of the ugliest ).

 

[Luis C]

I believe that in a matter of a couple of months, the VAST majority of the issues many have posted here against tubes will be moot. TubeDriver BLUE tube output technology is so revolutionary that EVERYONE will be not only be able to enjoy all the benefits of tubes without the limitations but they will be the most affordable tube technology available.
Take a look at www.tubedriver.com for the current car audio product. I a couple of months, this revolutionary technology will be made available for the home audio and HT enthusiast.

 

[Larry B]

Merc:

Irrespective of your wife's knowledge (or lack thereof) about tubes, the fact that she knows which tube she put in means it is a SBT, not DBT. I point this out not to invalidate your conclusions, but simply to make sure we all use the terminology correctly.

larry

 

[John Morris]

Larry B: Well maybe, maybe not. The way that we do this is by her selecting the tube with her eyes closed and then inserting the tube while looking downward. She only knows which tube she inserted AFTER I have listened to it and made my notes. She notes the tube model after removing it and then makes note of which tube it was. The tubes themselves look identical and can only be identified by carefully looking at the sides with some small numbers printed on it. In fact, from all the switching, most of the printing has now been rubbed off of the tubes and it is getting very hard to identify each tube without very careful examination. I thought about covering the printing that is left on the tubes with white tape with the letters A,B,C, etc, but was worried that the tape adhesive may melt onto the tubes...
However, I am not sure if breaking the blind, after each tube is tested, and before ALL the tubes are tested would still qualify for a DBT study?

 

[Larry B]

Merc:
Well, you have certainly thrown a kink into what I thought was a straightforward issue.
Larry

 

[John Morris]

Larry: We had to do that because after listening for a couple of tubes, I started guessing by the look on her face when she tried repeating a tube out of sequence. I wanted to remove all possibilites of my guessing which tube I was listening to...

 

[Larry B]

Merc:

I wanted to remove all possibilites of my guessing which tube I was listening to...

Yup, that's the reason (or at least, one fo the reasons) they invented the DBT.

Larry

 

[Saurav]

There's one way to get around that - she flips a coin several times, and writes down A/B/B/B/A/... based on the result of the coin flip. Of course, you don't know this information. Then, she selects tubes based on that sequence. That way, you won't be able to see her trying to decide what tube to pick, and this will reduce, (thought probably not eliminate), any subconscious/body language/facial expression issues.

 

[Larry B]

Saurav:

, any subconscious/body language/facial expression issues. [emphasis added]

That's why it's not a DBT.
Larry

 

[John Morris]

True DBT REQUIRES that NEITHER the investigator nor the subject have any idea which unit is being tested. That's why true DBT would require either some shield such as a AB box, or an external facia that is identical for all tested units. For pre-pros, you would also have to make sure that no OSD is ever flashed during testing.

 

[Saurav]

I know It would be closer to a DBT than with the switcher trying to pick options on the spot, so comparitively it could be better. But, you're right, it's not double blind.

 

[Larry B]

Saurav:
If the "switcher" knows the identitity of the product being tested, it's not a DBT. Were this a clinical trial, the FDA would read us (actually, Merc ) the riot act for conducting it in the manner he described.
Larry

 

[Saurav]

We seem to go around in circles. I thought I said that I agreed it wasn't double blind. It was single blind, but IMO picking the sequence in advance is still better than the switcher trying to pick options on the spot.
Is that clearer?

 

[Larry B]

Saurav:

It was single blind, but IMO picking the sequence in advance is still better than the switcher trying to pick options on the spot.

Seems logical.
Larry-trying-to-get-back-on-track-B