Yes, Dick should avoid a gross mismatch for sure. Should he hunt for a 10-16 ohm speaker for the review? No, not so much.
I will read the other reviews to see the speakers that were used. |
It's always about the amp/speaker synergy...always. That is why, for example, the Inspire amp may not sound as good on a particular set of speakers. All about the synergy. Dennis uses good trannys on his Inspire amps as an FYI.
I love this thread as I read the whole thing last night! My speakers are 90db efficient and 8 ohm. They to not dip below 6 ohms and are pretty easy to drive. I have tried several 7 - 12 watt SET amps and find I get enough volume....with the right music. The type of music played is a factor we need to add to the amp/speaker synergy equation.
If one listens to jazz, small ensembles etc, then I found 8 watts was plenty with my moderately efficient speakers. This type of music is not as demanding on a system. Now play some music that is dynamically challenging, then the lack of watts and lack of headroom is readily apparent.
So in addition to the room size and prefered volume level, one needs to take into account what type of music is played most of the time.
Rebbi, I think you made a wonderful choice with your AN kit and view your blog almost daily. Someday I will build a nice SET amp and actually looked at yours pretty seriously. I wish AN offered the same essential amp with no electrolytics and no circuit boards as a kit. It would most likely require a larger chassis to fit the ASC or GE oil caps etc...
Are any of you aware of a SET kit that uses all point to point wiring and no electrolytic caps? I would also like to try transformer coupling or direct coupling in this SET amp.Not sure such a beast exists in KIT form? |
Interesting spec on the Coincident EL34 amp. I think Al is spot on with his answer as to why. It is cost related and gives the builder an opportunity to make the best quality output tranny within a smaller range of ideal operation.
A typical SET amp has an output impedance of some 3 ohms (no feedback) with many under that. Speaker matching is especially critical with this amp. I think Dick O. got it right in his review warning folks to be careful and clearly showing the sonic results of mating this amp with a "typical" speaker. Not sure it is his responsibilty to hunt for a particular speaker for the review? Maybe it is? |
Yes, my statement also said they were high quality trannys made to play within their limited range of greatness. My goodness an amp priced this well, point to point wired, and that is beautiful to look at, has to save $$ somewhere. |
Any opinions on direct coupled 300b SET amps? Any owners here that can comment on not using a transformer or capacitor to couple? |
Ya, I am looking at it.... |
I listened to the top Supratek DHT, two box, tube regulated preamp last week. It has a switch allowing the owner to switch between transformer coupled and capacitor coupled. I prefered the capacitor coupled option as the highs were less grainy, more extend with improved smoothness. It this design the transformer option limited the top end.
This got me to thinking more about direct coupled as the best option. It is an interesting design. |
Forgot to mention I bid up to $1250 on that direct coupled set of 300b amps. I just did not want to go higher without hearing them! |
Not arguing which sounds better as they both have tradeoffs I have heard in various preamp designs from Coincident, Supratek and others. I just wonder if direct coupled is the best option for sound quality. The scematic looks pretty simple really on the EP 300b DRD amp. May be worth building a set of these?
Jet, the voltage on a 300b DRD amp is 700VDC! |
Jet, I am going to build a set of 300b amps or heavily modify an exsisting outstanding specimen. Just doing my research now and learning all I can before I decide on the direction. I came close to building the AN Monoblock amps with the two 300bs in paralell. I am not sure I want them transformer coupled however. I would also like the ability to switch from one to two 300b output tubes depending on the type of music being played.
The Manley Neo Classic amps fit the bill and I bet with the right mods/upgrades they could be wonderful. Not sure however, as they are built with circuit boards which I don't as much as point to point wiring. |
Jetrexpro, read up on the Manley Neoclassic amps. They have such a switch and custom tranny. Interesting.
Charles, well my speakers never dip below 6 ohms and are about 92db efficient. I also sit nearfield. The key is I don't listen to music at high volume ever. No louder than 85 DB continues on a day I am off the leash.
My current tube amps put out some 20-25 watts in triode mode and I never push them hard at all.
Like to have two amps on hand. My powerful SS amps and a tube amp to put into rotation. |
Joining the DHT SET amp world next week with a unique 845 amplifier designed by Larry Moore of UltraFi. His Monaco 845 design. The 845 tube is not pushed to its max and thus the amp put outs 10 watts, not the typical 20-28 watts per channel. DHT 45 tube drives the DHT 845. The amp is massive weighting in at just over 80 pounds or so.
Five separate power supplies! Yes, I said 5! I'll report back next week on the sound & synergy. |
Correction. 6sn7 feeding 46 feeding 845. The power tranny weights 35 pounds by itself! The design brings the very best qualities out of these 845 tubes by running them at their sweet spot tonally. |
My current speakers are rated 90-92db and do not drop below 6 ohms. My prior Coincident Total Victory III speakers were 12 ohm and 95db effecient. Ok, all that is on paper, but my newer speakers seem easier to drive than the prior Coincident speakers.
Remember, I do not listen to loud music. Most of the time I am under 80db on average. My speakers sound great at moderate volumes. I also sit less than 8 feet from the front plane of the speakers with the speakers pointed right at my ears...substantial toe-in.
I will let you know how the combo works out. My expectations are high as the amp is said to play much louder than its rated power.
I currently use a PP tube amp in triode mode putting out about 20-25 watts per channel and I have never come close to using all that power. My main amps are 300 watt SS monoblocks. I will trade between them and one tube amp. So this new SET amp will go up against my highly modified pair of PP tube amps for second position. I like to have both my reference SS amps and a good tube amp. I just love the sound of tubes sometimes. This is especially true for female vocal and jazz. |
We listen at the same volumes it seems. Yeah, C weighted.
Charles, due your amps hum/buzz at all through your speakers? If so, how loud is it? Hear it 2 feet away only? |
I read those also and was intrigued. I should have it by next Friday. |
