[Cliff B.]

please...
After visiting RMAF this year with my wife, we heard a lot of great systems, but one really stood out. I think it was the room with Zesto tube monoblocks. We weren't looking for $19,000 amps so we didn't really pay much attention to the exact setup. In any case, my wife said yesterday that she REALLY wants tubes so she can hear that rich, glorious, holographic sound again.
We auditioned a Primaluna Dialog amp in our house a few years ago, but it just didn't work out so we returned it.
I'm seeking advice on getting into tubes but our situation can be a bit complicated and will likely change entirely in the coming months. (moving) So first off, what is the preferred route to achieve that rich midrange tube sound, with truly Holographic imaging while maintaining detail and resolution of the remainder of the audio band. Should I look for a tube preamp, or amp (integrated is ok too)?
I might be willing to give up some of the low end because I have some REL subs that could be integrated into the system. If a preamp could give us what we want, that would be preferable especially if it has Home theater pass thru.

We would likely experiment with different setups. One setup would have Kef LS50 speakers (85db) and an Odyssey Khartago amp (100w) occasionally substituting ACI Sapphire XL speakers (85.5 db), the other has Vienna Acoustics Beethoven Concert Grand speakers (91 db) and an EAD Powermaster 2000 amp. For the first system, I would be willing to replace the amp with a tube amp if I can't get what we want with a preamp only. A preamp would work best for the second system due to it being part of a 5.2 channel Home theater setup. But, if a preamp alone can't deliver the sound we want and we have to go with an amp, then it would only be used in the non HT system. But I might rotate the VA speakers into that system occasionally, just for fun. For clarification, initially I would prefer to start with only one component (amp or preamp) and I would rotate it occasionally between systems.
As for price range, well, I would like to keep things in the $3000 range + or - a bit, used if possible so I can get more for the $$. Also, I wouldn't mind having something modded to achieve tube nirvana.
I realize that this covers a lot of ground, so perhaps start by discussing the qualities of tube preamp vs amp.
Thanks for your help,
Cliff

[sonicboom]

IMO it's unlikely that you'll achieve the big tube sound that you're after just by the use a tube preamp ahead of an SS amp. I'm sure others will disagree, but this has been my experience thus far. In your price range for used tube amps, you could try the Quicksilver V4 mono's and the earlier (series 1) VTL MB-185's. I haven't heard these two in quite some time, but they do fit your description of what you're after to a fairly good extent.

[Cliff B.]

IMO it's unlikely that you'll achieve the big tube sound that you're after just by the use a tube preamp ahead of an SS amp. I'm sure others will disagree, but this has been my experience thus far. In your price range for used tube amps, you could try the Quicksilver V4 mono's and the earlier (series 1) VTL MB-185's. I haven't heard these two in quite some time, but they do fit your description of what you're after to a fairly good extent.

Interesting that you mention the V4's, I heard them recently but didn't give them a good eval because I wasn't thinking about buying tubes at the time. I'll have to revisit them.

[undertow]

Well a few things reading your post... First your talking about all very low efficiency speakers @ 85 db. Most of the "Glorious lush tube" sound comes from much lower power amps using anything from 5 watts to 50 watts. In your case you would be pushing it to get into that envelope with such low efficiency speakers in my experience, and opinion.

Many people like Audio Research amps with the KT120 tube's simply due to the heightened dynamics with pretty good power output to work with their lower efficiency Dynaudio, Wilson Audio etc... dynamic drive speakers normally netting anywhere between 82 and 87 db sensitivity. But they are not really "Tubby" or romantic sounding amps. Unless you step up to more efficient speakers in general from my view you will be battling your way up trying to get the effortless "romantic midrange" which in general will require using the lower power amps that would produce it for you. Even the DHT amps like 211, 845, 300B etc...

So that being said any tube amps that might have the drive you need are probably on the lower end of the spectrum for the money something like a 80 to 100 watt per channel Rogue audio would match well to 85 db speakers. Will it be romantic or tube lush? Maybe, maybe not using most of the available KT88 or equivalent tubes.

I would first try a tube preamp with solid state amp as stated due to the efficiency of your speakers. My suggestion is not going with something like BAT or Audio Research, but more of a used Conrad Johnson or Cary Audio type design with good NOS tubes that consistently prove to be a more "Tubby" sounding in the preamp world. Also, EAR, or Audio Note designs, maybe VTL, Manley or similar would keep you a bit more in the fuller lush sounding tubes for preamps, but many can sound as solid state as solid state preamps do so tube rolling some different types of tubes unfortunately is a whole other game you sometimes end up in.

[undertow]

I assume below are the amps your referring too? So basically like I stated above you could probably do pretty well with any of your speakers running a pair of Rogue Audio mono blocks well below 3000.00 bucks used, but again getting the right KT88 or KT120 tube in them is another story. I can say most of the KT120's I tested can be a bit sharper for sure, but with your 85 db speakers might be a great balance. [And note these Zestos you heard are very powerful tube amps at 150 watts per side]... Your speakers would possibly struggle with anything below 80 or 50 watts... 100 watts is probably a good bet. But that means more tubes, more heat, and more cost unless you up the efficiency of your speakers to something in the 97 db plus range, and it opens a whole new world of good options.

Rocky Mountain Audio Fest 2015 • Hot Product





Zesto Audio’s attractive range of tube electronics continues to expand, taking a serious step up in both ambition and quality with the new EROS 300 monoblocks. The class-A amps run six KT88s a side and deliver 150 watts from an auto-biased circuit with zero global feedback. Input can be balanced or single ended. The sound with big-band music was impressively dynamic and rhythmically tight, clear, lucid and articulate, with a natural warmth and rich tonal palette. Priced at $19,900/pair, these Zesto amps offer an interesting alternative to the rash of KT120/KT150 amps hitting the market.

[FullRangeMan]

Welcome Cliff.
By what you said you want the SE magic.
You would look for low power Single Ended amps, not a Push Pull amps.
To pair low power amps is need hi sensitivity 8 ohms speakers.

I would suggest a Alnico fullrange driver as Nirvana Classic10Alnico:
http://www.commonsenseaudio.com/an10classicalnicospecs.jpg
or Super10CF for more efficiency in a big BassReflex box:
http://www.commonsenseaudio.com/an10classicspecs.jpg

About the amp you would not go wrong w/Decware ZenTriodeEL84 (2W Stereo, 6W in mono) or Decware Rachel EL34(6W Stereo, 12W in mono).
If you live in a cold area tube are great and lasts more.

[SteveFord]

Another question is how loud do you listen to music?
I have low efficiency speakers (Magnepan) and occasionally crank it up a bit and the rooms are fairly good sized.
EvaAnna Manley said I'd want 250 watt monoblocks so that's what I went with (but from VTL, not Manley).

You really need both a tube preamp and tube amps to get the sound you heard. 
Look into Audio Research, deHavilland, Conrad-Johnson and the latest AVA products for preamps; all of them should do the trick but they're all different flavors, too. 

[ketcham]

I would believe you can source many tube amps used and find what you are looking for in budget.   That said, maybe PS Audio dealers can offer a reasonable discount on gear.  If so, look at: http://www.psaudio.com/products/bhk-signature-amplifier/  This has good reviews at the RMAF this year.  This would solve the issue of your speakers being inefficient and difficult to drive by your typical tube amp.

[Cliff B.]

Undertow, yes, those are the objects of my wife's lust. I understand your point about efficiency. Thanks to the others for their replies also. We listen to mostly acoustic instrument music plus classical, jazz and classic rock. We don't play at extremely loud levels. This will likely end up in a small to medium sized room like a large guest bedroom, but not master bedroom sized. Since I'm in the early stages of exploring this topic, all of the suggestions so far are quite valid. Those full range drivers are interesting.
keep the ideas coming...
Cliff

I assume below are the amps your referring too? So basically like I stated above you could probably do pretty well with any of your speakers running a pair of Rogue Audio mono blocks well below 3000.00 bucks used, but again getting the right KT88 or KT120 tube in them is another story. I can say most of the KT120's I tested can be a bit sharper for sure, but with your 85 db speakers might be a great balance. [And note these Zestos you heard are very powerful tube amps at 150 watts per side]... Your speakers would possibly struggle with anything below 80 or 50 watts... 100 watts is probably a good bet. But that means more tubes, more heat, and more cost unless you up the efficiency of your speakers to something in the 97 db plus range, and it opens a whole new world of good options.

Rocky Mountain Audio Fest 2015 • Hot Product





Zesto Audio’s attractive range of tube electronics continues to expand, taking a serious step up in both ambition and quality with the new EROS 300 monoblocks. The class-A amps run six KT88s a side and deliver 150 watts from an auto-biased circuit with zero global feedback. Input can be balanced or single ended. The sound with big-band music was impressively dynamic and rhythmically tight, clear, lucid and articulate, with a natural warmth and rich tonal palette. Priced at $19,900/pair, these Zesto amps offer an interesting alternative to the rash of KT120/KT150 amps hitting the market.

[JackD]

Cliff

I understand that you can't tell this at a show where they are running the A/C at full capacity, but amps like the Zesto will raise the room temp in a room the size you are talking about 10 degrees in a short time.  To keep that room bearable in warmer months you would have to drop the temperature to the rest of the house a significant amounts.  In my 15 x 19 x 10 dedicated room my mono's with a combined (4) KT-88's are almost unbearable in the warmer months and generally only get used from December to March.  The Odyssey Kismet takes their place in warm weather months.  If that is not an issue then with those speakers in the mix you will need to look at higher power options.

[sunnydaze]

I would seriously consider more sensitve speakers.   That makes your amp universe much much wider.   It also means you won't need to spend as much on an amp.   Hi quality hi output tube power is expensive!

Personally I won't own an insensitive speaker below say 89db.  I just refuse to be limited to a SS arc welder, or a really expensive high power tube amp.  Just too many really good low and med power tube amps out there,  which is where my sonic preferences lie.   And I believe this path,  sensitive spkrs + low / med power tubes,  gives the best chance of obtaining your stated preferred sonic flavor,  for the least coin.    Additionally, if you are willing to buy used and some lesser known fringe names you can get incredible sound on the cheap.   

Thats what I did and I scored two really good (but unknown) SET amps and a great Will Vincent Baldwin organ amp rebuild,  all between $800 - $1200.  Over my 20 yrs in this hobby I have owned many pricier name brand amps,  but these are some of my favorites.

(If interested,  details are on my system page)

[JackD]

Cliff

If you are looking for a tube amp to use in the room you described with the KEF's or ACI's you could get away with one of the higher powered Line Magnetic integrated amps or if you want even more power the Rogue Cronos Magnum. If you go in that direction I would move the Khartago to the other room in place of the EAD. Then you could use a Candela with HT bypass.

[rpf]

Cliff

I understand that you can't tell this at a show where they are running the A/C at full capacity, but amps like the Zesto will raise the room temp in a room the size you are talking about 10 degrees in a short time.  To keep that room bearable in warmer months you would have to drop the temperature to the rest of the house a significant amounts.  In my 15 x 19 x 10 dedicated room my mono's with a combined (4) KT-88's are almost unbearable in the warmer months and generally only get used from December to March.  The Odyssey Kismet takes their place in warm weather months.  If that is not an issue then with those speakers in the mix you will need to look at higher power options.

IME this is an exaggeration. I've run various single and mono-block tube amps in rooms that size (with lower, 7 1/2 to 8 foot ceilings) and have experienced only an increase of a couple of (maybe a few) degrees in temperature. I've never had a problem running them in summer, which is the only time I've even noticed the heat they put out. This could, of course, vary depending on where you live. (This was in lower NY. I'm now in FL and have no problems here either but have a much larger room.)

Yes, amps like the Zesto that are running a total of 12 power tubes will raise the temperature in a room much more significantly but there are many amps - rated from 60-100 wpc - that use only 4 power tubes that will drive your speakers, though I would stick with the higher end of that scale (say 75-100 wpc). Quicksilver Mono 90s or Mono 100s, Rogue Atlas, Stereo 90 or Stereo 100, McIntosh MC275 (various iterations), etc.

IME a tube pre-amp alone won't get you the full three dimensionality and harmonic accuracy of a tube amp.

[Escott1377]

Have you considered bi amping?  For me, bi amping gave me the perfect blend of tube "magic" while maintaining a tight low end.

I have a pair of Prima Luna's for my mids / tweeters and I had not heard them until they arrived at my house.

IMO, they provided a better tube sound than Cary or Manley that I previously owned.

This would allow you to maintain your SS amp and put the money into a quality tube amp.

Good luck!

[Cliff B.]

Have you considered bi amping?  For me, bi amping gave me the perfect blend of tube "magic" while maintaining a tight low end.

I have a pair of Prima Luna's for my mids / tweeters and I had not heard them until they arrived at my house.

IMO, they provided a better tube sound than Cary or Manley that I previously owned.

This would allow you to maintain your SS amp and put the money into a quality tube amp.

Good luck!

Actually, I was thinking generally along this line. I would power my two way speakers (these can't be bi-amped) with the tube amp and let my REL sub handle the low frequencies. This assumes that I'm using a preamp with either a sub out or pre-out. Or I could use an output directly off the DAC for the SUB. I had originally just planned to use the high level input on the REL, but that would mean taking the "tube" signal off the tube amp. If the tube amp doesn't give great low end resolution then that might not be a good way to go, hence the need for a preamp or DAC with sub or extra pre out. Doing as I described would also need the ability to set a crossover in the DAC. The Oppo 105 will handle these issues for now.

[undertow]

I would not run a sub off the DAC directly unless it has a built in volume control, and your controlling the entire system master volume off that DAC with no other preamp in the system. Plus it is unlikely you will have a DAC with Dual preamp outs to run both your sub, and main left right channel amp unless you use a Y-splitter which I highly recommend AGAINST. Basically you will have to keep getting up or using a remote controlled sub to try and match the volume coming out of your sub with the preamp every time. Many tube preamps have dual stereo outputs, that's all you need to run your main amp whether it is tube or not in the end, and a subwoofer all off the same volume control via preamp.

[Escott1377]

I recommend using a Y from your pre on each channel, then feeding your right tube / right sub and left tube / left sub.

This way you can set your output level on your sub and keep is consistent.

I have found that less is more with dual subs in my set up.

You mention multiple subs in your OP.

[Cliff B.]

Here is a technical question. Can I run two sets of speaker wires, from two different amps, to one set of speakers. Only one amp would be turned on at a time. For example, I might have a solid state amp hooked up to the speakers for HT duty, then when done watching a move I might want to listen to two channel music with a tube amp so I turn off the solid state amp and turn on the tube amp. Is there a problem doing this without using a switchbox, just have both amps wired direct to the speakers?

[Bill Baker]

Here is a technical question. Can I run two sets of speaker wires, from two different amps, to one set of speakers. Only one amp would be turned on at a time. For example, I might have a solid state amp hooked up to the speakers for HT duty, then when done watching a move I might want to listen to two channel music with a tube amp so I turn off the solid state amp and turn on the tube amp. Is there a problem doing this without using a switchbox, just have both amps wired direct to the speakers?

The short answer is NO. You cannot have two amplifiers hooked up to one pair of speakers at the same time. You would have to have some type of switching devise or change speaker cables when you want to use one amp or the other.

[FullRangeMan]

Do he is refer to bi-amp?
Amp 1 on at woofer.
Amp 2 on the tweeter.