Yes, triode and pentode are different. And they even measure differently on the outputs. They also sound different, a bit.
TL, FWIW, I actually have a trolling permit, but I don't use it any more. 😉
TL, FWIW, I actually have a trolling permit, but I don't use it any more. 😉
No problem, it's always interesting to know what you're working on. Re the rest of your post, that ties in exactly with my comment to Scott about my new portable digital recorder- I spend years lugging around a modified Ampex 351 (15ips, two track), and advances in technology have given me something with even better performance, much lighter weight, longer recording time without changing media, and a price comparable to a few reels of tape.
Quite a few other things change beween triode and pentode mode too. The open loop gain of the amp will be lower in triode and this will among other things affect GNF levels (I assume the amp has GNF since it has pentode mode as an option).
The triode strapped output tubes will have higher grid capacitance too, which may be a problem depending on the ability of the driver tubes to drive the grids. A triode design may also ask considerably more of the driver stage in terms of voltage swing; the driver stage had better be linear...
The couple of times I have heard switchable pentode/ triode amps I preferred the pentode mode, but no doubt a series of factors lead to that conclusion.
The triode strapped output tubes will have higher grid capacitance too, which may be a problem depending on the ability of the driver tubes to drive the grids. A triode design may also ask considerably more of the driver stage in terms of voltage swing; the driver stage had better be linear...
The couple of times I have heard switchable pentode/ triode amps I preferred the pentode mode, but no doubt a series of factors lead to that conclusion.
Yep, I tend to prefer pentode mode, too. Except with a new crossover I happen to like triode better on this particular amp. It could be an output impedance thing, as SY mentioned.
^me too, i find pentode mode with screens supplied thru lowimpedance power source as having better dynamics, tighter bass than say ultralinear mode.....
To some, the evidence may lay only in the results of scientific studies.
To others, the evidence is by the degree they enjoy listening to reproduced music.
Usually, people from one group will never agree with people from the other group, thought there are some rare exceptions, people who have one foot in each of those approaches.
Indeed, and also (generally speaking) triodes are far more linear than pentodes.
In only one amplifier that I owned which had such a switch, I preferred the sound of the triode mode, however, in triode mode that amp didn't have enough power to control my speakers tight. So I don't own that amp anymore.
SY,
Let me see if I have your stance correctly, you would like to see a double blind test showing that every assertion about perceived audio quality made here is properly verified?
Or are there some issues or levels that you believe have already been shown to exist? If so could you show at what level items such as THD, IM distortion, bandwidth etc. are an issue?
I can point you to some tests done in the late 30's that show extended bandwidth beyond 5 kc.s (30's for labels!) was undesirable. It was of course later understood what issues they actually missed.
Do you have a problem with Joshua following his own ears? Or do you think folks here will be misled by his stance?
There are levels of difference among what is perceived, yet we all get a chuckle out of some of the claims.
Maybe for the holiday of lights I can get both of you a 'bot, one to post "I heard it therefore..." and the other "Show me a real test demonstrating... "
ES
You're all over the map here. Want to try one at a time, just for clarity? Answer to the first question is no.
And I think everyone should follow their ears. I've probably said that a hundred times in this thread. How many more before it sinks in?
Ah, so we disagree even on the simple stuff. I consider part of my job to give people what they need not what they think they want.
As an example I have an arena where the frequency response is not uniform throughout the seating area. To improve that as requested, adds more loudspeakers which does provide more uniform coverage when looking at the frequency response. Of course the speech intelligibility drops when you add loudspeakers in the same acoustic space. (The correct solution is of course to fire the announcer who seems unable to identify what a microphone actually is.)
Back when I sold stereos the rule still held. There was the guy who came in punched the loudness button, turned up the bass and the treble down, listened to all of the speakers and picked the set that sounded the best to him, along with a receiver. Not my customer, so he went home with them. The next week when he came back with blown woofers and receiver, I walked him through a few basics, he really didn't believe me, he being a "musician," Of course he did take home the loaner gear and never came back for what he had before.
The general rule being most people don't hear a difference either at first or even going from good to better, but let them listen a bit and they won't go from better to worse.
Now who can guess what instrument he played?
- Status
- Not open for further replies.