From the specs,
These speakers need a welding machine type of amplifier that very hardly can be found among tube amps or even class A SS amps don't ya think? |
Hi Mondie. It's Christmas and some food for thought! The KR Enterprise amplifiers were developed by the late Dr Kron in the Czech Republic. His tube designs are perhaps the most unique in the industry and sound very special indeed. Certainly worth some investigation if you plan to use tubed amplification. I believe there is a pair presently in the Gon classifieds. The individual has a well written caption accompanying his add. You may want to check it out. Personally... I wouldn't use an autoformer either as it does indeed have some sonic liabilties . I am not that well versed with the current crop of solid state stuff. The only solid scrape amplifier that I ever really cottoned to was the 25 watt/ch Bedini 25/25[it's a real honey] and perhaps the original 25watt Mark Levinson M2 monos.I used both of these pure class A amplifiers to drive stacked Quad 57's in their day. I still have my Bedini to this very day and listen to it periodically for comparison purposes. I will probably keep it another 20 years as well. Regardless of the tube or solid scrape choices, the lower powered examples of each have traditionally outperformed their higher powered bretheren in my experience. Looking at the high sensitivity of your speaker choice,you may want to investigate looking into David Bernings designs as well. Audiogon member Twl uses a custom version of Berning's brilliant OTL design that is very very unique . Tom is a very accomodating individual with many years experience in the audio arts per sey.He uses a speaker design with a similar sensitivity rating as yours. Enjoy the Holiday! cheers David |
Hi all,
Thanks for the interesting discussion.
My speakers are Equinox Jupiters, link here;
http://www.equinoxaudio.com.au/products/speakers/jupiter.php
Eccletique, l have decided not to go down the autoformer road. Decware's amps look like a possibility, going SS is also. Never heard of KR aplifiers, will do dome more googling!
Merry Christmas all.
Cheers Simon |
Loudandclear. On the contrary...there is no such thing as too much power regardless of the speakers sensitivety. To begin with.... I am sure muralmans recommendation of the h20 was not even power related. While I have never heard the h20 amp, given the fact that Mondies speaker's impedence load can dip down anywhere near 2 ohms,I would think Muralmans recommendation is a certainly sound one[pun intended]! Hell...a 2ohm impedence load is getting dangerously close to a dead short for crissakes. Seems like Mondie would like to marry his speakers to a tube amp. Unfortunately... there are very few push/pull tube amps that can remain stable driving a 2 ohm load [let alone a set amp] without oscillating itself into china syndrome. Mondie... The only set amp that I am aware of that may be able to handle your speaker is the KR amplifiers. There are a few push/pull ones as well. Just be sure they have no less than 4 ohm impedence taps off the transformers and preferrably a 2 ohm tap. The original quicksilver 60 watt monos,the ones that employed the 8417 output tube[not the kt88] were champs at driving loads below 4 ohms. They were very musical even in stock form; and with a little updating with modern caps and resistors they should be a real treat. The older vac pa90 mono's are another great amplifier that would easily be up to the task. These el34 based amps can be used in pure triode or ultralinear at the flick of a switch. They also have a 2 ohm tap from the transformer and massive power supplies that are fully regulated. I am sure there are a few others out there as well. Best of luck in your search and have a very Merry Christmas! |
Loudandclear, Mondie's speakers dip down to 2 ohms. That is not SET territory. The question here has centered around that disparity. I just believe there are better ways than going with autoformers. |
muralman,
While I share your enthusiasm for the H20 amp, It would not be my recommendation it for some one with 96db speakers looking for a SET 300B based amp.
250wpc would be a bit much here. |
Hey Mondie. Just curious about the speaker you are trying to drive? |
The H2O, reviewed here, is stable to at least 1 ohm, 76 db. I know. That is what my speakers are rated. The stereo version of the H2O sells for $2500. |
Reubent,
Thanks for the Decware suggestion. l have spent the last couple of hours searching for info on them. They are very highly regaraded and can handle the 2 ohm load. Look like a great option and with a return policy too got to be worth considering.
Cheers |
Simon,
For a nice, natural sounding solid-state amp, you might want to consider the Channel-Islands VMB-1. I own a pair of these relatively inexpensive solid-state mono-blocks and they are very good, even spectacular considering the $999 list price. And they come with a generous return policy.
There are some comments about them on the AudioCircle web forums.
I really like them. They are 40 watts/channel, small and generate almost no heat. They are a similar design to a GainCard or GainClone amplifier. These are sometimes also referred to as "chip amps".
I have currently replaced a series of tube amps with the CIAudio VMB-1s and don't miss a thing......
Enjoy,
TIC |
Thanks for all the great repsonses.
While not what l wanted to hear it seems there are other options l can look into. l will check out the Decaware and impedance matching autoformers. l am matching upto a Supratek Cabernet so maybe a solid state amp may be OK. l am sure there are nice, natural sounding ones out there, l just havent heard them yet :)
Anyhow, enjoy your Xmas break all.
Cheers Simon |
Don't be red Gregadd,
You could use it as a preamp or 300B power amp 2W/ch onto 8Ohms.
To 2Ohms probably not even half-watt. |
I own 2 amps that can easily handle the load:
Dynaco ST-80 (1996 by Panor)-great EL34 amp that is switchable triode or ultralinear and has 2 ohm taps.
Grommes G101A Monoblocks-amazing 30 year old amps that handle down to 1.4 ohms with no sweat using 6GT5 tubes. This amp is fast, tight and clean.
I'm not giving mine up but, I can help you find some of your own if you need.................. |
DUH? My face is red. Isn't the 300B a preamp?
gregadd |
Sdatch is right, with the Speltz autoformer you could make the impedance load appear to be anything from 2 to about 20 OHMS and several selections in between each with a different sonic flavor. Try them they are fun. |
If you really wish to keep your speakers, you may want to consider an impedance matching device, like Paul Speltz's ZERO autoformers (http://www.zeroimpedance.com). I have been evaluating them in my system for about 2 months, and have been pleased with the results. Mind you I purchased them not as a long term solution to keep my speakers, but more or less so I could continue listen to music at a high level of resolution while I attempt to find an 8 Ohm speaker that is complimentary to the rest of my system. Also, the ZERO autoformers seem to be system dependent - in other words YMMV. |
The Decware Zen/Select amps love a 2 ohm load. I have a friend that purposely builds a series of speakers with 2 ohm impedance specifically to be used with the Decware amps.
If you can live with about 1.5-2 watts/channel, it might be a good choice. Of course, you could buy/try/resale a used one and lose nearly nothing since they are inexpensive to start with and hold their value pretty well.
BTW, I don't own a Decware amp, but I have a few friends that do. They love them and I've heard their systems. They can be very good in an appropriate system.
Enjoy,
TIC |
Twl's answer is right on target.
. |
Not a suitable combination.
Efficiency match is ok, but the impedance match is poor. Look for an 8 ohm speaker for this amp.
If you want to keep the speakers, then you need an amp capable of low impedance loads, which is not any SET amp, nor most tube amps in general.
There are some tube amps that can do it, like a Wolcott, but under 2 ohms is generally SS territory. |
