Should I go for a SET?

robert1325 · « **on:** 20 Nov 2006, 04:32 pm »

HI,

At the moment I'm using a solid state 2x100W. amplifier with blaudio (chinese) 90db/8ohm bookshelfs ( they have dynaudio drivers)

Sources are : analog bolder squeezebox 2 / jolida jd9-thorens321-sme3009-dl103

I'm using this setup in a small room of 3x3 meters...

Is a SET tube amp possible in this setup? I am thinking about something el34 based or if I save up some more money 300B.

My music taste is very big ( jazz, rock, hiphop, pop.............)

Thank you,

Robert

Dmason · « **Reply #1 on:** 20 Nov 2006, 04:41 pm »

Nothing with Dynaudio cone drivers will be suitable for SET amps. Dyns need LOTS of current to do their thing. In fact, you could use more than what you have, to get the most out of the speakers you do have.

For SET amps, look for speakers without crossovers, and with benign impedance modulus, with greater sensitivity than 93db, preferably 95db and above. High pass at the amplifier >70Hz to relieve both amplifier and speaker of bass duty, and augment bass.

robert1325 · « **Reply #2 on:** 20 Nov 2006, 04:48 pm »

These speakers are just new

Are there other tube amps that will drive them?

That's dissapointing, I was looking forward to get some SET magic

miklorsmith · « **Reply #3 on:** 20 Nov 2006, 04:49 pm »

Yep, even a small room won't compensate for the lack of drive, especially with bass-heavy genres. You might be able to get an acoustic guitar to sound good, but as soon as the jump factor goes up, you'll be out of gas.

If you really want to give it a whirl, I'd check out some of Louis' fine speakers at Omega.

Ideally, the doc's right, keeping the SET out of the low bass entirely is ideal. This adds complexity though, and you might get satisfactory results in your small room with a nice pair of widerangers.

miklorsmith · « **Reply #4 on:** 20 Nov 2006, 04:51 pm »

Try a tubed preamp with 6sn7's with your existing amp. I'm sure the Dmason could direct you to some he likes.

robert1325 · « **Reply #5 on:** 20 Nov 2006, 04:53 pm »

There's no input for a pre... Should I get a SS power amp and a tubed pre?
I'm looking for a more involving sound .... Could be a bit more open to.

And a SET connected to a subwoofer's crossover? Would that be ok?

miklorsmith · « **Reply #6 on:** 20 Nov 2006, 05:04 pm »

Quote from: robert1325 on 20 Nov 2006, 04:53 pm

There's no input for a pre... Should I get a SS power amp and a tubed pre?
I'm looking for a more involving sound .... Could be a bit more open to.

And a SET connected to a subwoofer's crossover? Would that be ok?

Having not heard your setup, it's difficult to advise. If you're prepared to swap amp and pre, why are you unwilling to consider other speakers?

Do you mean plug the line-level output from your preamp into the sub, then line-level out from the sub to a SET amp for mains? I think this would cause more harm than good. I certainly wouldn't buy a SET amp hoping this worked out.

jon_010101 · « **Reply #7 on:** 20 Nov 2006, 05:10 pm »

Would you consider a triode push-pull amp? I have no problem driving similarly-inefficient speakers with 15 watt triode Williamson amps. My friends are typically blown away when hearing Tribe Called Quest on this system.

robert1325 · « **Reply #8 on:** 20 Nov 2006, 05:12 pm »

What I meant was, SET- speaker cable- Subwoofer- speaker cable- speakers...

I really like my speakers, and they are just new ( Went from floorstanders to Bookshelfs) I bought them thinking the effiency would be enough for a Tube amp.... Would a higher powered (kt88) work better?

Don't worry about giving the wrong advice... Just want to have some opinions from experienced people

robert1325 · « **Reply #9 on:** 20 Nov 2006, 05:13 pm »

As a long as the sound is good, I don't mind push - pull... I just want the tube sound like my dads audion 300B 25watt push-pull monoblocks ( he's using B&W 801 S2's )

But people seem to prefer SET....

miklorsmith · « **Reply #10 on:** 20 Nov 2006, 05:36 pm »

The primary appeal of SET amps is their simplicity. A SET to single-driver is about as simple as an amp/speaker interface can be. Many believe simpler circuits do less damage to the recording and allow a better emotional connection to the music.

SET amps are not stand-alone entities, that is they do nothing on their own. Of all the choices in amplier type, they are The Most Dependent on their speaker buddies. They are not tolerant of impedance dips, do not have driver "control" in the typical sense, and obviously have little power. They NEED a copascetic speaker match. To do otherwise is myopic and assumes the amp is the only source of the magic.

I can envision a couple of ways your subwoofer scenario might operate and none are good for this application.

Lots of people really dig push-pull amps. You've heard good ones at your dad's place. Try borrowing those. Anything you can do on a trial (free) basis will be good at this point. You need more power. Would 18-watt KT88's be enough? Probably not for pop/hip hop. There are big tube amps out there.

You say you "really like" the speakers, but if you're genuinely tube curious, they're holding you back already. And, I sincerely doubt your monitors will ever sound like B&W 801s which are probably in a much bigger room.

toobluvr · « **Reply #11 on:** 20 Nov 2006, 05:45 pm »

Try an amp that is triode / ultralinear switchable.
It is not SET but it will give you a taste of the same magic.
And it gives good flexibility to mate with various musical genres.
Grunt, control and pop for the big dynamic stuff, and sweet refinement for
the more simple and acoustic stuff.

Probably many choices out there, but Manley Snappers come to immediate mind.
And so does my ASL AQ1001-DT which, lucky for you, I just happen to be selling!

Great control and bass, with refinement, finesse and tube flavor.

http://www.audiocircle.com/index.php?topic=33030.msg299350#msg299350

dado5 · « **Reply #12 on:** 20 Nov 2006, 06:20 pm »

Depending entirely on how loud you listen, in terms of subjective volume, your max will be about half as loud as your current set up if you go to an EL34 or 300B SET. Your pop's amps will give you a very good idea of both the subjective volume (25 watts is not going to play substantially louder than 8 watts) and 300B sound.

SETs can be deceptively powerful because they do not go into crazy distortion when their nominal power rating is exceeded and they effectively have instant overload recovery. Personally, I replaced an 80 watt KT88 push pull amp with a 300B SET on 89 dB speakers and did not notice a difference. No doubt if I had really pushed the volume on both the 300B would fart before the KT88, but I apparently did not reach that level in normal listening.

Crossing out the bottom two octaves to a dedicated amp is good advice for any system but especially for SETs as it alleviates damping concerns.

robert1325 · « **Reply #13 on:** 20 Nov 2006, 06:32 pm »

Now I'm really confused!

It does make sense to me, those 25 watters of my dads go very very loud... Why wouldn't 8 watts be enough for my small room? I tried his amps in my setup once and did not go past the 9 "o-clock

I don't want to ignore your comments, as I've never tried a SET in my setup... and surely you people must no more about it.

miklorsmith · « **Reply #14 on:** 20 Nov 2006, 06:36 pm »

Are you expecting consensus on an audio board?

robert1325 · « **Reply #15 on:** 20 Nov 2006, 06:38 pm »

Haha, no everyone has their own opinion

It's just that I'm getting really confused about people saying SET is fine for their inefficient speakers while other say it's not very good.

But push - pull seems to be the saver bet in my case

robert1325 · « **Reply #16 on:** 20 Nov 2006, 06:40 pm »

Those xiang sheng amps look very interesting :

http://www.pacificvalve.us/XSD2020AKT8.html

http://www.xshn.com/office/home.asp?class=16&serial=English

jon_010101 · « **Reply #17 on:** 20 Nov 2006, 06:43 pm »

Quote from: robert1325 on 20 Nov 2006, 06:32 pm

Now I'm really confused!

It does make sense to me, those 25 watters of my dads go very very loud... Why wouldn't 8 watts be enough for my small room? I tried his amps in my setup once and did not go past the 9 "o-clock

I don't want to ignore your comments, as I've never tried a SET in my setup... and surely you people must no more about it.

If you never listen above, say, 80-85dB, in your 12x12 room, I see no reason why a SET 300B or triode-wired KT88 wouldn't be enough for you (it would be plenty for me in my similar room, I listen around 75dB). Especially considering your speakers are rated at 8 ohm / 90dB.

But if you do need a bit more grip on the bass, or want to rock out, push-pull triode is a nice compromise. The biggest advantage of push-pull triode over SET would be improved damping factor, rather than power -- Better bass definition and "rhythmic drive".

toobluvr · « **Reply #18 on:** 20 Nov 2006, 06:53 pm »

Quote from: robert1325 on 20 Nov 2006, 06:32 pm

Now I'm really confused!

It does make sense to me, those 25 watters of my dads go very very loud... Why wouldn't 8 watts be enough for my small room? I tried his amps in my setup once and did not go past the 9 "o-clock

I don't want to ignore your comments, as I've never tried a SET in my setup... and surely you people must no more about it.

Depends on how you listen.
And it depends on how "kind" your speaker is.
For me, in a 10 x 10 room, and at my preferred listening levels of about 75 to 85 db max, I'm quite sure SET would suffice. Particularly since we are talking about monitors with small drivers that are usually not too difficult to control.

I say usually because it is not always the case. And sensitivity numbers don't always tell the story. Some 90 db speakers are kinder and subjectively easier to drive than other 90 db ones. Also, don't forget to consider the impedance curve. Fairly constant over the frequency range with few dips is best.

I have owned several SET amps, so I do have some experience. I have used them to drive monitors and big floorstanders in the 90 to 94 sensitivity range, and in much larger rooms than yours.

While I think 300B would work, for another option I recommend looking into an 845 amp. I prefer it to 300B. It is a very gutsy tube and compared to 300B, ballsier and better (more extended) at the extremes, yet is just as sweet and palpable in the mids. And the 845 outputs 22wpc vs the 8 wpc offered by 300B. But don't be fooled, it is a very robust 22 watts and works just fine on the right speaker. But it's all about synergy and matching, and I am not familiar with your speaker sufficiently to know how much power, drive and control it needs.

robert1325 · « **Reply #19 on:** 20 Nov 2006, 07:07 pm »

Thank you, this makes it a lot easier for me to chose an amp, Those 845 tube are monsters!

Is SET really that much better than Push-pull triode? The 845 tube seems a very interesting choice.