|
Audio Asylum Thread Printer Get a view of an entire thread on one page |
For Sale Ads |
99.244.190.183
I'm having problems to find a quiet amp for my 105db speakers. I had tried few 2A3,45.46 and 300b amps and all have some noise floor (buzz) and some even mechanical transformer buzz. Auralic Vega to be used as a preamp.
Please recommend only if you have/had listen to that model.
Thanks for Help.
Follow Ups:
My Fi 421A is just about dead quiet on my horns. My DIY monoblocks are dead quiet (even with ear 1" from drivers. My 300Bs were dead quiet but I converted to AC on the 300B and now I have have a small amount of Hum but I can convert back if I need to (will use a Tentlabs filiament or just a decent CLC design). Lots of commercial designs have poorly designed power supplies and are noisy. I used to own a set of Wavelength 300B monoblocks and they were extremely quiet.
Korneff 45 Wavac Mastersound VIVA Art Audio all worked well on my horn systems.
So after I got my la scalas, it was basically like hooking my stereo up to a signal tracer and cranking the gain all the way... Hum, hiss, thermal noise, ticking sounds, insanity... The amp was fine with normal speakers but this is a true torture test. I found the following helps:
1. Try grounding the amp chassis directly to an earth ground
2. Try substituting all the small signal tubes, a mild heater to cathode short can be a huge problem
3. A marginal solid state rectifier diode can make a spike which makes intolerable
Buzz... Way worse than just him... Try to scope the output and make sure the hum is not actually buzz
4. Crappy DC filament supplies for output tubes can create lots of problems... If it's just a rectifier and a capacitor it is almost worse than running AC
5. Tube shields need to be intact and functional
6. On one system I put a 10k reaistor across the high impedance input and a 100k reaistor in series with preamp output... This served the dual function of vastly reducing preamp noise and also reduced hum pickup for the first stage of the amplifier
7. Grounding and layout are critical... Even a tiny amount of power supply ripple current in signal ground can create major hum problems.
Guitar amps are high gain and have high efficiency speakers... Lots of info online for reducing hum in guitar amps applies here too
You could consider non-tube amps. Sinful suggestion on this forum, but ...
I have Unos and have recently decided to move to SS for a number of reasons, but only if I can enjoy the music as much as with tubes. I've tested and rejected a number of candidates, but have recently bought an Accuphase Class A amplifier - Model A36. I'm still getting it settled in before doing a meaningful comparison with my (very quiet) 845-based mono amps.
Accuphase is certainly dead quiet, has better controlled bass than you're likely to find with tubes, has adjustable gain switch (4 positions from 16 to 28 dB - very welcome with high efficiency speakers) and SE and balanced inputs. Looks rather retro with its VU meters but immaculately built
SS amps tried and rejected:
Red Wine - maybe a good amp with some speakers but truly dreadful on horns
Sugden Class A - quite good but not quite there
Benchmark (raved over by a Trio owner) - dead quiet, sadly rather dull - one wants to turn volume down rather than up
Quad Platinum - a non-starter
Merrill and Devialet Digital - actually very good but sniffed at by most conservative-thinking audiophiles. Soon we'll all be using digital amps I believe - with mixed emotions. There's now a range of excellent modules that even the best-regarded companies are starting to use. It's a matter of finding one that mimics our favoured SET sound.
Lavardin and LDF are amps I'd really like to have tried but I've not managed to get my hands on either
I'll report back soon on the Accuphase. Encouragingly there are other Avantgarde owners here who choose Accuphase.
Peter
Thanks Peter, I was tempted to SS like First Watt J2 or the newer F7.
I also read a lot about Benchmark AHB2 but can't find it in Toronto and does not apply 30 days to try it in Canada.
I have 99 db/w speakers, so I don't have quite the issue with potential noise. I have heard the First Watt J2 on my system (borrowed from a friend for two weeks). These amps sounded very good, for solid state, but, the sound was still very much in the solid state camp--slightly artificial "edge" to the initial attack of notes, not quite as full sounding (harmonically rich) and smaller sounding soundstage. Still, I would have no problems living with that amp. Oh, by the way, it sounded dead quiet.
Operationally, the J2 was also easy to live with--no turn on or turn off noise (big deal with very high efficiency speakers). The only "issue," which is common to all solid state gear, is that it took more time from turn-on to sound good than would tube gear.
With speakers as efficient as Nano, and particularly with bass being taken care of by a built-in amp, my own preference would be for low-powered tube gear, whether SET or pushpull. I own both a parallel 2a3 SET amp (Audio Note Kageki) and a pushpull 349 amp (re-built Western Electric 133a); both sound good so I am not convinced of the inherent superiority of SET vs. pushpull. Both are quiet enough for my purposes. The Kageki is now being used by a friend who has a very large horn system (107 db efficient) in a fairly small room. I did not find noise to be an issue at all (he is very good at setup, so I am sure he found ways to keep noise down that I would have missed). I think it IS possible to utilize low-powered SET amps in your system; it just might take a little bit of work.
My brief investigations into First Watt (and recommendations from actual users) seem to suggest that you should be looking at the SIT models. Our AG speakers don't need 30 watts and why Push Pull? We tend to regards SE as preferable in tube amps, so presumably SE SS amps may be nicer sounding than PP SS amps.
Peter
Peter do you own a SIT from Nelson Pass?
I asked him and he recommend me J2.
Srajan from 6Moons say F7 for lower gain. I'll drove the amp with my Vega dac preamp.
So many versions/flavour.......kinda lost
Hi Aaron,
I use a First Watt F2J clone, and it is absolutely silent even with my ears a foot away from my speakers. This amp is known for its low noise floor. A requisite statement that I must make is that my speakers are Hornshoppes, which are around 95 dB efficient however.
The sound of the F2J has a lot in common with SET amps.
Cory
Not even seen a First Watt amp! There's only the distributor here in UK (no dealers) and, although I've spoken with him, I rather doubt he has any units for demo. The SIT's 8 watts is still far more than your 2A3 amp.
However it was probably in High Efficiency that I saw recommendations for SIT amps - maybe in this thread - http://db.audioasylum.com/mhtml/m.html?forum=hug&n=172875&highlight=cawson&search_url=%2Fcgi%2Fsearch.mpl%3Fauthor%3DDman%26forum%3DALL%26sortRank%3DNone. You may find more helpful into on that forum as they discuss both tube and SS gear.
Yes, the more you look into these things, the more confused one gets! Part of the fun, but possibly costly mistakes along the way!
Peter
aaron1608,
Get in touch with Jack Elliano (electra-fidelity) in Las Vegas. He makes excellent and quiet SET amps. I have a pair of his 50 tube mono blocks with silver output transformer secondaries that are VERY quiet on 106db horns.I am sure there are other amps that are fairly quiet that I have not heard but it will be a trial and error proposition. Noise is an accumulation of ALL the components in your system, not just the amplifiers.
I also had good results with Art Audio 300b amps,very good sound,fairly low noise. Each individual system will vary, and there is no reliable way to predict how much total noise your system will have. Good luck.
First thing you do is to turn on the amp without the preamp. Short the RCA in jacks on the amp and listen to the sound of just the amp and the speakers. Half the time a "noisy amp" is really a sensitive amp with an overblown / high gain / noisy preamp.
Any little tube rush or hum that you'd never heard on a typical system sounds like a jet engine and as soon as you notice it, it's all that you hear.
It's tough to say what will work for you. Often, I have to float the grounds which is more of a ground loop buzz. Or change tubes. That said, my Wavelength Geminis are as close to dead quiet as you can easily get. Another 300B amp worked great on a 95db speaker, but hummed like a banshee on my horns.
Still, to an extent, when you get into the 105db range in speakers, you will hear any buzz or hum if you try. A slight hum that you only hear with your head next to the speaker is likely the best that you'll get. Perfection will be elusive, IMO.
Just keep trying and returning candidates.
-Rod
"Just keep trying and returning candidates."
Unfortunate in Toronto,Canada dealers don't have in stock many SET's nor to let me listen in my system.
Hence my asking for A direction.
Have you tried first watt SIT?
No,not yet.I am still SET guy at my heart. :-)
Yeah, I know the problem.
Unfortunately, many of the better SETs are expensive and specs don't really help. And there are plenty of variables, a noisy tube or as Chip mentioned, a poor match with the preamp.
I was fighting some hum for months and finally replaced all my preamp tubes and then had to swap 6922s a few times to get the right mix. Beware that any recommendation might not work for you.
How does the system sound with your old amp or a SS amp? Is it quiet?
-Rod
I sold my japanese 2A3 and have no amp now. It was perfect with Coincident 95db but not anymore at 105db.
Post a Followup:
FAQ |
Post a Message! |
Forgot Password? |
|
||||||||||||||
|
This post is made possible by the generous support of people like you and our sponsors: