Forums - To preamp or not to preamp

CAJames

Seasoned Member

"I've run every
red light on memory
lane."

Posts: 1672

Re: To preamp or not to preamp
Reply #50 - 09/24/23 at 04:39:12

Quote:

Posted by: My Name is Earl

... here’s what I think is going on. Low powered SET amps need sufficient gain when driving even moderately efficient speakers...

Yes, but.... you never mentioned what your source is. Any amp needs a certain level of input to reach full power. For the UFO amps it is 1.5 volts. Most sources these days will output more than 1.5 volts and can easily drive a UFO to full power, but maybe yours doesn't so a preamp is needed to provide the extra gain.

What I think is going on, and what has been my personal experience for many years, it that a tube preamp adds just a little bit of secret sauce to the sound that makes it seem bigger/better/louder even though the amp isn't putting out any more watts. JMO/YMMV and all that, but I can't imagine having a system without a tube preamp.

FWIW I started my career in physics, and I like to say I worked my way all the way down the ladder from scientist to programmer to system and network administrator.

Back to top

[FOOBAR2000 | Jay's CDT2 MRK3] -> Denafrips Terminator 2 + Gaia
Sumiko Pearwood -> Mapleknoll Athena -> Luxman SUT -> Maple-tree Phono 3E
Woo WA22 -> 2x UFO25s, balanced monos
Omega SAM , Hifiman Arya, Senn HD-650

IP Logged

whynotnothing

Verified Member

Posts: 6

Re: To preamp or not to preamp
Reply #51 - 10/04/23 at 13:26:09

My UFO2 will arrive any day now and I've got a chance to grab a Lab12 Pre1 at a good price. This got me thinking. My understanding so far was that my current DAC can output 2V and that technically I don't need a pre-amp.

However, it would seem according to this thread, that a preamp would add flexibility in terms of changing the sound signature with the gain riding.

So essentially, if my understanding is correct, with the high gain of lab12 pre1 and ufo2 in the chain you could get a similar signature as to say what Tori can do, and obviously you could reduce the preamp gain and bring back the smoother UFO2 signature.

Thomas and stereo did a review of Tori mk5 and ended up saying that UFO2 is the sweeter and his preferred amp, but that it's not either/or situation and that unfortunately for our wallets he'd like to have both at disposal. So my thinking is that with a pre-amp I could achieve a similarish thing as having both amps at disposal, but at a far lower cost.

Also, prior to reading this I had an idea to eventually get a 2nd amp in the system, a Line Magnetic with a 845 power tube - to quote Herb Reichert "To my ears, a properly designed amplifier using directly heated thoriated-tungsten tubes always sounds more vivid, elegant, direct, and brilliant". Same thing applies here, if the preamp gain helps with the "body, vividness" etc. then depending on the results, there's no point in going for the secondary amp for the different sound signature.

I might've oversimplified a bit, but hopefully it does make some sense?

Back to top

IP Logged

CAJames

Seasoned Member

"I've run every
red light on memory
lane."

Posts: 1672

Re: To preamp or not to preamp
Reply #52 - 10/04/23 at 16:02:39

Quote:

Posted by: whynotnothing Posted on: Today at 05:26:09

...So essentially, if my understanding is correct, with the high gain of lab12 pre1 and ufo2 in the chain you could get a similar signature as to say what Tori can do, and obviously you could reduce the preamp gain and bring back the smoother UFO2 signature...

I guess I might quibble with the idea that adding a preamp will make your system sound like a different amp. But it will make your system sound a bit different in a way that most people like but is difficult to predict precisely. It will certainly give you added flexibility in tuning your system to your liking, both through gain riding and also the selection of tubes for the preamp, in addition to tubes in the UFO2.

Back to top

[FOOBAR2000 | Jay's CDT2 MRK3] -> Denafrips Terminator 2 + Gaia
Sumiko Pearwood -> Mapleknoll Athena -> Luxman SUT -> Maple-tree Phono 3E
Woo WA22 -> 2x UFO25s, balanced monos
Omega SAM , Hifiman Arya, Senn HD-650

IP Logged

whynotnothing

Verified Member

Posts: 6

Re: To preamp or not to preamp
Reply #53 - 01/08/24 at 12:06:26

Of course CAJames, you were correct. I didn't quite get what I expected, nevertheless, the experiment was valuable. I actually prefer to turn the UFO2.1 all the way up and control the volume with the lab12 pre1 remote. Just prefer and enjoy the amp purity as opposed to the lab12 body and smoothness most of the time. Not yet in the mood for tube rolling the pre1 but feels good to know there's flexibility there when the time comes. Been a great listening and learning experience.

Back to top

IP Logged

JOMAN

Seasoned Member

Posts: 763

Re: To preamp or not to preamp
Reply #54 - 01/16/24 at 15:09:58

Quote:

Just prefer and enjoy the amp purity

I've been following this thread and I find the quoted comments interesting. Not disagreeing in any way, after all a lot of what we prefer tends to be subjective. However, after reading a number of posts, I'm of the opinion that we take for granted a very key component... the room....

Quote:

https://www.decware.com/cgi-bin/yabb22/YaBB.pl?num=1659750827

It is my opinion, FWIW, that until the final component, the room, is addressed we will never hear the actual purity of any upstream component. I have worked with my UFO25 at some length. Tube rolling, upgrading cables and upgrading sources. The realization that I came to was that as I removed handicaps I became aware of just what the UFO25 strong suit was... transparency. It has no particular sound, so to speak. It will let you hear whatever it is that you put in front of it.

Having said that, the room will affect what it is producing, so that once again, you never really get to hear the "purity" of the amp. Not everyone can treat a room. I'm in the process of putting together my sound room and it will be compromised to some degree as I really don't want a "butt ugly room" (subjective of course). But I do want a significant degree of improvement through strategic room treatment.

My conclusion based on my experience is that often times I was compensating for the room acoustics when I was tube rolling or changing cables etc...

Did the amp sound different as I made changes? Of course it did. Did it sound like another amp? It never sounded like any other amp that I ever had but then I haven't listened to all the amps that are out there not even all the Decware amps, so I really can't say.

So what's the point that I'm trying to make? It isn't that we all have different rooms and different preferences, that's obvious. I guess it would be that we need to keep in mind the whole context of what effects what we hear otherwise we could end up coming to conclusions that in themselves are subjectively correct but objectively misleading.

Back to top

IP Logged