|   Couple of basic tube questions | Chuckd55
May 2, 2002 8:28 PM | | Since I know virtually nothing about tube gear, could someone please tell me:
1) If tube amps go up to 20 kHz why don't cymbals and brass instruments sound the same as on SS? There seems to be a lot less high frequency information when playing tube stuff.
2) Does tube amplification imrpove the soundstage? I thought it was only the speakers and room that did this. If tube gear does affect soundstaging, is it due to harmonics or what?
3) Are there any tube amps with tight bass? Is this even possible? What about SET's, are they any different from vacuum tube stuff?
Thanks,
Chuck |
| Generalization need not apply | Mwalsdor_cscc_edu
May 3, 2002 8:58 AM | | I get the impression that you believe or assume that tube amps or even SETs sound one way and SS amps another. Not all amps, regardless the topology, sound alike. What a PARTICULAR amp sounds like has everything to do with the amp's topology, the execution of the design, the parts used and the voicing and design skill of the designer. In addition tube amps are tuneable with various tubes, one of their many attributes. They are very sensitive to internal part upgrades, if you are so inclined.
Speaking of soundstaging; tube components in general are known to throw a wonderful expansive, and layered soundstage. But this is affected by the room, acoustics, speakers, front-end, cables. In other words - many things.
Bass performance. Speaking of "tight bass". My little SET amp has incredibly tight and tuneful bass. You should remember that an amps performance is limited by the partnering speaker, so we need to look at them as one (1) component, not seperate. SET amps are "vacuum tube stuff", just another type of tube amp. Hope this helps.
MikE
http://www.svetlana.com/docs/tubeworks.html |
| What tube amps have you listened to and in what systems? | Chris Garrett
May 8, 2002 10:15 PM | | Your questions seem to be loaded, but I'll throw you the bone.
Many tube amps do cymbals just fine. You're just used to the tizziness of SS amps and cheap digital, which really don't do trebles very well. The treble is the Achilles' heel of both.
The way the record/cd was mixed, affects soundstage too. If the idiot engineer felt that every instrument needed to be on top of each other, that's what you'll hear.
My Cary SLAM 100 monoblocs set to Triode and running at 95w have pretty tight and tuneful bass powering my Dynaudio Contour 3.0s. I listen to a lot of electronic and reggae music.
My Wright Mono 8 300b monoblocs putting out 8w, but powering a 100db efficient pair of '74 Klipsch Cornwalls, produce tight bass as well.
Anymore questions?
Chris
PS: You should really try and hunt down some nice tube systems and give them a listen. Much better, IMO, than lowly rendered SS stuff. |
| What tube amps have you listened to and in what systems? | Chuckd55
May 17, 2002 9:34 PM | | Waytech SET with Brentworth Type 3A speakers lacked bass belwo 60 Hz and high end estimating over 10 kHz.
Unison research SET seemed okay but I compared to another unison Research vacuum tube model and not to S.S.
Rogue Audio with MeadowLark Shearwaters. Seemed to calm down the bright (IMO) highs but bass got too loose but even with Krell S.S. the bass still seemed loose. But now as bad as the Rogue. |
| re: Couple of basic tube questions | dr_no
Jun 22, 2002 9:54 PM | | 1) Good tube equipment will give great cymbals and brass sonics. It does cost more for good tube components, so you will need to spend some money.
2) Good tube amplification will open up a great soundstage, although you are correct that room, speakers are also responsible. It is true that some tube equipment has some harmonic and IM distortion and adds " texture" to the music. I would check for distortion when checking brands.
3) There are tube amps with tight bass. SETs are known for low bass output, but usually tight. Horns ususally only go to 70hz (50hz on some expensive models) and fall off at approx 36db per octave. Some counteract this by placing speakers in corners of room. However, Dr. Bruce Edgar manufactures a subwoofer, which helps with the bass.
If you want good bass and highs, might consider good Pushpull amp and regular speakers with good natural damping properties. |
| Good article to read concerning SS. | dr_no
Jul 10, 2002 10:04 PM | | Dear Chuck,
There are many problems with SS that are not usually thought of. A good article to read is at:
http://www.sasaudio/theory6a.htm
It gives some good data and theory. Another problem is feedback in some tube amps (and SS amps for that matter) through the power supply, that change the sonic characteristics of a component.
Electronics do indeed change the soundstage.
Tube components can give good, tight bass, but a low Q speaker (natural damping) helps. |
| re: Couple of basic tube questions | skeptic
Sep 2, 2002 12:38 PM | | Tubes in and of themselves have no sound of their own. Many tube amplifiers do not perform well for some or all of the following reasons:
1. Tubes have a high plate impedence which translates into high output impedence compared to the inherently low output impedence of common collector transistor circuits. The output transformer used to lower the impedence adds more problems due to magnetic circuit losses and nonlinearity. We call these losses hysterisis and eddy current losses and has to do with the way the transformers are made. The results are poorer speaker damping and therefore less tight bass and more distortion and less clarity at high frequencies.
2. It is harder to design and build a good power supply for tubes than transistors because they operate at much higher voltages and the best parts are no longer as readily available as they once were. Getting the right transformers and filter capacitors is hard. Poorer power supplies translates into poorer bass among other things.
3. But transistors have their own problems including "crossover notch distortion" to which they are particularly vulnerable, especially bipolar transistors. This translates into a harsher distorted sound that initially may seem more brilliant.
The forgoing are just generalizations for which there are many exceptions. There are excellent designs and examples of both types but IMO, the best tube amplifiers of today cost much more than transistor amplifiers of comparable quality only because the parts for tube circuits are so much rarer these days.
What are some good examples of each? Good tube units from yesteryear included McIntosh and Marantz. Dynaco was also very good. There are similar types available today but at much higher prices. Good solid state types? How about Mark Levinson?
Which sounds better? That's impossible to say. Each individual must make up his mind for himself. |
| re: Couple of basic tube questions | dr_no
Oct 18, 2002 3:08 AM | | 1) Cymbals have harmonics that extend past 100khz. Tube, especially SETs have trouble extending that high (usually -3db at 30 to 40khz and already dropping off at 20khz). Some brands use better high frequency tubes, but even then may drop off at 55 to 60khz. Good PP amps extend to -3db at 80khz or so. The sound does improve.
2) Good tube components usually extends the soundstage.
3) All triode amps can have pretty tight bass. But you also need speakers with a low Q, say approx 0.6 or so.
4) SETs usually lack in bass, may require subwoofer as horn systems usually drop off at 50 to 70 hz at, if I remember correctly, 36 db per octave. You may place horns in corners for a little deeper bass, but imaging and depth will suffer. You will also probably notice the soundstage coming at you, which you may not be accustomed to. I would stick with PP tube amps.
Hope this helps. |
| |
