Need some Tube and Class A SS Suggestions


I recently purchased a pair of Spendor D7s and am just loving these speakers. I have them paired with a musical fidelity KW 500 integrated. The combo is super fast, tight, and dynamic. However, the Spendors can be a bit too revealing in the high frequencies given a harsh or bright recording. This has me headed down the rabbit hole of tube amplification and possibly Class A SS. If the lowest bass is not as tightly defined I'm ok with. It actually may be too tight and defined at the moment. Added warmth in the upper bass would be fine as well. And if I'm going to upgrade then maybe it's time for separates too!

Here are the power amps I'm considering:
  • Primaluna EVO 400
  • Pass Labs XA25
  • Line Magnetic 805IA
  • Schiit Aegir Monoblocks - the price is just too good.
And on to the preamps:
  • Rogue Audio RP-5 and RP-7
  • PS Audio BHK Preamp
Ideally I would find at least one of the two Pre/Power used. I can probably get about $2200 for the musical fidelity so budget would be about $6k or so assuming I can somehow get both items used.

I'm curious to hear if any thoughts on what I've picked out already and if there are other units worth looking.

Thanks!
shahram
I have TAD ME-1 speakers and a Vinnie Rossi LIO DHT preamp. I have a Coda Contiuum #8 amplifier on the way and I’m expecting a good result. I will report back.
I think Sugden would be a good match with your Spendor speakers.
Yes - I've heard that as well. Problem is finding a dealer around here that carries them...
I use Quicksilver tube gear with my Spendors and Harbeths and the combination is outstanding!
http://quicksilveraudio.com/
What Spendor speakers do you have? The classic line?
How many hours are on your D7's? I have a pair and they take quite a while to run in.  At 150 hrs you will notice the tweeter more relaxed and they keep improving so up to 500 hrs.  Well worth giving them time and the music sounds great along the way.  

I took a similar approach as you with my D7's as they are the most "hifi" sounding component in my system. Class A solid state amp coupled with tube linestage and tube phono stage.  The Pass XA25 will be a great match especially if you pair it with a tube linestage.  I use a XA30.8.  You will get the sweetness and open presentation of the tubes but with some bottom end grip that SS provides. I pair the XA30.8 with a VAC Ren MKV with NOS Mullard 6922's and I get everything that I need in terms detail, tube goodness, grip, texture, natural presentation, and balance evenly across the sonic spectrum.  With the amazing imaging, ability to convey tactile elements of music (they are really fast), and amazing bass down to 29hz, the D7's deliver a lot of value for the money in a fairly small package. I don't have experience with the preamps you're considering but I think you're on the right track assuming your musical priorities are similar to mine.

Enjoy!
The A-line stand mounted! I have owned other Spendors with Quicksilver and they always sounded good!
My D7s have probably 200 hours on them or so. Maybe a bit more. I actually have noticed the tweeter evening out a bit. These were a demo pair at a dealer and they were not sure how much it had run in before I bought them.

Anyway, class A amp and Tube Linestage is sounding more and more appealing to me. A bit of sweetness up top is all I really need. Thanks for the feedback.
Carver Raven 350’s (tube)
older McCormack rehabbed by steve.
used pass labs amp,

 too many ways to go.

 There’s a McCormack on flea bay in a gold revision for 2K
    There’s a Threshold stasis 300 also on flea bay.  
 Happy hunting.
so mnay good amps out there.

happy hunting!
First time poster here, but I've been following this forum for a while. I was compelled to comment here because my experience is eerily similar. I have the D7's with a Hegel H80. This combo is also fast, tight and sometimes too revealing. I'm also desiring some mid-bass warmth. I think with the H80 I haven't tapped into the full dynamic potential of the D7's.

Like you I'm also considering higher power tubes amps or SS class A (which I've never heard).  But, I'd like to stick with an integrated. I'm looking now at a Primaluna Dialogue HP or Vincent SV700 for my budget. 

Out of those you have listed, the Line Magnetic would be my top choice. But all of your options look like they'd be a great match. I don't have any direct experience with any of these so I'm looking forward to seeing where this thread goes and what you choose.
Why do guys say too revealing when what they mean is the top end and transients are hyped? Or is it grainy and edgy? Because the one thing it can't be is too revealing. I mean that is the whole entire goal, to reveal what is on the recording. Reveal. Yes. That is exactly what we want. Cannot possibly have too much of it. No. I do not think you are using this term correctly. Not at all. 

I'm gonna guess from the word "too" that what you're trying to say is something is exaggerated. But what? Attack? Transients? Top end? 

Whatever it is, if you want to have any chance of success you need to figure it out. 
@millercarbon is correct here.  The D7's aren't too revealing and that's a fairly nonsensical term I agree since it is an attribute we desire.  In my experience over the past 2 years with these speakers is that the tweeters need some run in to shed some initial grain and edge.  I first heard the D7's at a show and was hugely impressed.  I knew that Spendor didn't bring any D7's to shows with less than 500 hrs on them so I wasn't alarmed by the run in period needed.  They really have one of the most amazing tweeters I've heard...which I'm sure led Stereophile to write this  in its review: 
I noticed especially fine treble dispersion and extension, as well as freedom from any harshness. The treble had a crystalline clarity that put the Spendor D7 among the finest speakers I have heard at any price.
The tweeter clarity is at a level that most speakers don't possess.  They also have a fabulous midrange and bass extension while imaging at a level that I normally associate with nice stand-mounted monitors. In my system I truly enjoy the music that is conveyed through pairing the speakers with Class A SS amplification and a tubed pre that can operate in a fully balanced circuit from input to output. 
Post removed 
Regarding the EVO 400 possibility, while I couldn't find measurements on it many PrimaLuna power amps have particularly high output impedances, even for tube amps. If that is the case with the EVO 400, given the speaker's rising impedance in the upper treble region (see Figure 1 of Stereophile's measurements here) the result of that pairing may be an over-emphasis of the upper treble region, which sounds like the opposite of what you are looking for.

Regarding the XA25, which I own, I second the comment by three_easy_payments. And especially his suggestion of pairing it with a tube line stage. The XA25 is very transparent, and pairing it with a very transparent solid state line stage may be too much of a good thing, given what you are trying to accomplish.

Good luck. Regards,
-- Al

Other than the XA25 mentioned above, I recommend you check out the Musical Fidelity Nu-Vista 600. I listened to it recently with Spendor D9s, a very pleasing result. I imagine it would sound just as good with the D7s if not better
I would pair a Prima Luna tube amp with a Prima Luna tube preamp.  System synergy is key. 
@millercarbon
Maybe I am using the term revealing incorrectly. Maybe it's sibiliance in the high frequencies? I don't know, whatever it is it is uncomfortable to my ears at medium or high volume on certain tracks. A good example is the lead guitar on Wilco's Hate it Here. I don't ever remember this song as being bright. But don't get me wrong, this speaker is amazing in literally every other way.

@branches 
Interesting that we are in the same boat here! I'm curious to hear what you end up doing. I'm debating whether I should go all Tube or not. If for the only reason being that it sound fun. Haha.

@almarg 
You know what's funny I ready the same review and didn't quite put two and two together. I could trade in my amp to upscale audio and test out a Primaluna for a while to see if it works. In another thread on the steve hoffman forums about the Spendor D7 someone did comment that they heard the D7 with Primaluna gear at a dealer, which is the reason they bought the D7. So who knows.

Hard, bright, etched, edgy, strident, harsh, take your pick.

Put on a recording of massed violins in a symphony orchestra playing in a higher register fortissimo; if you don't want to listen or want to turn the volume down after 5 seconds, you know you've got a problem, however you care to label it.  As far as I'm concerned, this is the ultimate test for tweeters.

Other amps: tubes: look at some of the higher output integrateds from Raven.

Or class A SS: Sugden, Belles, or the standard fall-back, Pass.

High frequency distortion is ubiquitous and has many sources. If it was easy to fix everybody could do it. Some things in audio are mysterious and irritating.   
The only time I get infrequent high frequency distortion/edge/glare revealed by my D7's is with a digital stream in my system.  It never appears with vinyl. I use an Auralic Vega G1 and I suspect I'd need to move higher up in the market to get something digitally with a more organic presentation.  The thing is that I have zero interest in putting money into a digital front end.  Sure, it sounds pretty dang good but I use it mainly to explore new music and find new ideas for purchase on vinyl...or as background music while I'm working around the house.

I would be curious among this group whether they notice the strident tone only with digital as well.     
@millercarbon
Maybe I am using the term revealing incorrectly. Maybe it's sibiliance in the high frequencies? I don't know, whatever it is it is uncomfortable to my ears at medium or high volume on certain tracks. A good example is the lead guitar on Wilco's Hate it Here. I don't ever remember this song as being bright. But don't get me wrong, this speaker is amazing in literally every other way.

Okay. So is it uncomfortable because its too loud? Or because it is harsh or grating? twoleftears is right about the massed strings. Violins produce a sound comprised of lots of little bursts produced as the bow is drawn across the strings. There's several strings on the violin and a whole bunch more on the bow and so then when you get a whole section of them playing together a lot of components can't keep the details straight and they all congeal together and that can be painful. When if they are kept straight its impressively moving. One might even say exhilarating. 

Doesn't have to be massed strings. Could be soaring electric guitar, cymbals, anything loud and complex. The key is being able to keep all the many strands playing together separate.  

Then when you get a better handle on what it is, are you even sure its the speakers? Often times people blame (or credit) the speakers just because it seems so obvious, when it turns out to be the speakers are just putting out the signal that came in.
Well I upgraded from some older Monitor Audio Silver S10s, which are warmer and more forgiving to poorer recordings. I played them back to back on the same recordings and the MA is just not as bright in the treble. Midrange is more recessed and pushed back. Bass is warmer but not quite as impactful. I still have both speakers here so I can switch back and forth.

I'm going to give the Spendors more time to break in and see how it goes.
The only time I get infrequent high frequency distortion/edge/glare revealed by my D7's is with a digital stream in my system. It never appears with vinyl. I use an Auralic Vega G1 and I suspect I'd need to move higher up in the market to get something digitally with a more organic presentation. The thing is that I have zero interest in putting money into a digital front end. Sure, it sounds pretty dang good but I use it mainly to explore new music and find new ideas for purchase on vinyl...or as background music while I'm working around the house.

I would be curious among this group whether they notice the strident tone only with digital as well.

I've got a PS Audio Directstream with the Bridge II streamer. I am not hearing digital as being the problem. The same recordings on Vinyl have the same results for me.
I am in the same boat here. 
I have upgraded my system. Currently have a Linn Majik DSM (w/ amp and volume turned off) that feeds a Pass Labs XP-20 preamp and a 250 watt Bryston 4BSST-2 power amp. I have new demo Spendor D9s. Playing vinyl sounds awesome but certain digital recordings can have too much steel edge and grain. The middle and the bass are superb though.
Did some reading and it might be that the Bryston is a poor match with the Spendors. I was going to replace it and then Covid-19 hit. This is a remote location on a small island. So I have postponed replacing the amp with a warmer SS or tube base amp. 
But then it hit me: the sound is changing! Very, very noticeable: the highs are softer and more detailed with less reaching for the volume than I did when I first installed the Spendors. I have also been playing with the Linn Space Optimization system. Getting a better result with time and experimenting with the created Linn profile.

So, I am glad I did not rush out and get a new amp. I am in no rush to do so now. I will keep playing the Spendors and listening to their changing sound. I will then get a new amp as a test. No rush though. Who knows how this will work out?

Bottom line: I was somewhat on the fence with component & speaker break in periods? But these Spendors are opening up like a fine wine in a decanter...
I am in the same boat here.
I have upgraded my system. Currently have a Linn Majik DSM (w/ amp and volume turned off) that feeds a Pass Labs XP-20 preamp and a 250 watt Bryston 4BSST-2 power amp. I have new demo Spendor D9s. Playing vinyl sounds awesome but certain digital recordings can have too much steel edge and grain. The middle and the bass are superb though.
Did some reading and it might be that the Bryston is a poor match with the Spendors. I was going to replace it and then Covid-19 hit. This is a remote location on a small island. So I have postponed replacing the amp with a warmer SS or tube base amp.
But then it hit me: the sound is changing! Very, very noticeable: the highs are softer and more detailed with less reaching for the volume than I did when I first installed the Spendors. I have also been playing with the Linn Space Optimization system. Getting a better result with time and experimenting with the created Linn profile.

So, I am glad I did not rush out and get a new amp. I am in no rush to do so now. I will keep playing the Spendors and listening to their changing sound. I will then get a new amp as a test. No rush though. Who knows how this will work out?

Bottom line: I was somewhat on the fence with component & speaker break in periods? But these Spendors are opening up like a fine wine in a decanter...
Hey Photomax. Looks like fellow Spendor owners are following each other around on the internet :). I’m on the same Steve Hoffman thread as well!
Lol!

I spent a lot of time investigating speakers before I purchased my Spendors. Then came buyers remorse and doubts. But with each passing week I am liking them more and more...
I spent a lot of time investigating speakers before I purchased my Spendors. Then came buyers remorse and doubts. But with each passing week I am liking them more and more...
Yes the wine analogy is really on point. But I also wonder how much is the speaker breaking vs. the brain being broken in. I think it's a combo of both.
I would pair a Prima Luna tube amp with a Prima Luna tube preamp.  System synergy is key.
I wish I could, but my rack just doesn't have space for two 8 inch tall devices. And my apartment is very limited so a taller rack won't work either. One of either the preamp or poweramp needs to be like less 6.5 inches tall :(
Other than the XA25 mentioned above, I recommend you check out the Musical Fidelity Nu-Vista 600. I listened to it recently with Spendor D9s, a very pleasing result. I imagine it would sound just as good with the D7s if not better
Interesting suggestion. My Musical Fidelity has similar tubes in the preamp as does the the Nu-Vista 600. I wonder how similar they sound. 
A friend of mine had the Spendor D7s and was having the same experience as you.  He found the solution to be a Luxman tube integrated.  He later swapped the Spendors for Harbeths but that was also due to a problematic room.  Good luck as this problem must be solved!
I know a person who drive D9 with Line Magnetic 805 SET amp with satisfaction.

https://forums.stevehoffman.tv/threads/spendor-d7-speakers.717289/page-12#post-23429895

His nickname is "Freesole"
Violins always sound a bit screechy to me. I much prefer the cello. So maybe I’ve never heard a properly set up system.

How sensitive are the D7 to off axis adjustments? Can you tweak your toe in until they’ve settled a little more?
One of the handy features with Primaluna (that I never thought I would use) is the switch on the fly ultralinear/triode remote. I’ve used it with both Dynaudio and Zu speakers for recording specific flavor adjustments or just if I’m in a mood. The Spendor D7/D9 are on my short list of must audition. I bought a Primaluna with that in mind for someday. (A plan that is now on temporary hold.)

A friend of mine had the Spendor D7s and was having the same experience as you. He found the solution to be a Luxman tube integrated. He later swapped the Spendors for Harbeths but that was also due to a problematic room. Good luck as this problem must be solved!
Thanks for the info. Luxman stuff is really nice, but very pricy! If the right used item comes up I will pounce.
I know a person who drive D9 with Line Magnetic 805 SET amp with satisfaction.

https://forums.stevehoffman.tv/threads/spendor-d7-speakers.717289/page-12#post-23429895

His nickname is "Freesole"
Thanks. I've corresponded with him in that same thread. Unfortunately those Line Magnetic amps are like 10 inches tall and won't fit anywhere in my rack...
Violins always sound a bit screechy to me. I much prefer the cello. So maybe I’ve never heard a properly set up system.

How sensitive are the D7 to off axis adjustments? Can you tweak your toe in until they’ve settled a little more?
One of the handy features with Primaluna (that I never thought I would use) is the switch on the fly ultralinear/triode remote. I’ve used it with both Dynaudio and Zu speakers for recording specific flavor adjustments or just if I’m in a mood. The Spendor D7/D9 are on my short list of must audition. I bought a Primaluna with that in mind for someday. (A plan that is now on temporary hold.)
The Triode switch on the Primaluna amps is one of the primary reasons for looking at Primaluna. Just to switch up the flavor a bit if a recording is too harsh.

I'm leaning heavily toward an EVO 400 Power amp or the older Dialogue Premium HP and pairing that with a tube or hybrid preamp.
The Rogue Audio RP-5 preamp (or better yet RP-7) and Stereo100 amplifier are a stunningly magical combination.  
@avanti1960 

Howdy. Yes the RP-5 and RP-7 are on the shortlist for sure. I've heard good things about the Stereo100, but I think I going to avoid Rogue Audio for the power amp. Reading that I will likely need to change the tubes more frequently. Autobias of the Primaluna really is enticing to try different tubes as well.
Plinius class A should be on your short list.
Be careful buying used class A amps,they do run hot and heat is a killer with electronics.
I would pair a Prima Luna tube amp with a Prima Luna tube preamp.  System synergy is key.
I wish I could, but my rack just doesn't have space for two 8 inch tall devices. And my apartment is very limited so a taller rack won't work either. One of either the preamp or poweramp needs to be like less 6.5 inches tall :(
Just so you know, system synergy isn't the key. If you take a dull sounding amp and couple it with a bright sounding preamp, the result won't be neutral. Each piece in the system should stand on its own merits! You get far better sound this way and doesn't cost any more.
@atmasphere

Yes I agree with that. That's pretty much how I've been building my system slowly over time.

And the D7s are sounding better and better as the days go by with my musical fidelity integrated. This is allowing me to be rather patient with what I do next.
shahram OP

for tube amps, given the speaker’s rising impedance in the upper treble region the result of that pairing may be an over-emphasis of the upper treble region, which sounds like the opposite of what you are looking for.
What Almarg said here with many tube amps and the Primaluna could well happen, and be a bit forward/etched in the highs.

I suggest with D7’s 90db and this kind of impedance and -phase angle,
https://www.stereophile.com/images/0415-SD7fig1.jpg
go the XA25 or the XA30.8 and if they are too expensive a Class-A Schiit Aegir https://www.schiit.com/products/aegir
It will give a good 40watts of power into the bass with this loading and have that Class-A sweetness in the highs even though it’s just 20w Class-A into 8ohms.

Cheers George
Hi @georgehifi 

Thanks for the suggestion here. The impedence of that stereophile graph really doesn't rise until 10khz. A 10khz tone is VERY high pitched. Not much music above 10Khz so that impedence graph doesn't really bother me.

Definitely considering a Primaluna or Rogue Audio preamp with a class A SS power amp. I think if I went class A SS the pass labs XA25 would be my top choice. But part of me really wants to hear what this speaker can do with a Tube power amp...the dilemma continues!
I just ordered a Pass Labs XA30.8 to go with my Spendor D9s. Will be selling my Bryston 4BSST-2 amp...
shahram OP


https://www.stereophile.com/images/1214PLDPIfig01.jpg
Here is a behavior graph of the Prima Luna’s output transformer, as you can see it goes into stability ringing from 10khz up and the harmonics of that can effect even further down the line.
This combined with the high impedance of the speakers in the same area can be put to question.
Because the higher the impedance of the speakers, and if you look the output transformer ringing is worse at high impedance put the two together and you have something nasty going on.

Cheers George
@shahram   

But part of me really wants to hear what this speaker can do with a Tube power amp...the dilemma continues!

You likely won't come close to getting the low-end grip (both weight and speed) of SS with a tube amp and you will almost definitely get more noise.  I moved from a tube amp to SS with my D7's and knew the second I turned on my Pass XA30.8 that I had made a transformational improvement even moving to amp with half the watts as my prior tube amp. 
@three_easy_payments

Yes, i realize that low end grip might be compromised some with a tube amp. But I've read that newer tube amps from Primaluna and Rogue do not sound like the tube amps of yore...maybe I can find a dealer nearby that will let me borrow an amp for a fee to test it out.

What tube amp did you use previously? 

When you are listening at what you consider a loud volume, how far do you push the volume knob? Or where do you never go past on the dial?



@photomax

Congrats on the new amp! Is it brand new or used? Please share some thoughts on the pairing with the D7 once you've run them in.
I have D9s. I think they have about 275 hours on them now? They definitely sound smoother and more enjoyable. 
The XA30.8 is a new demo with almost no playing time. I am told it will take about five days of being on before settling in...
I bought a Belles SA-30 class A power amp to pair with my Graham Audio LS 5/9, they sound beautiful together, hopefully I can change my pre amp to a Supratek this year.
The Belles has only 30w in Class A, but it sounds very powerful, the snap of a drum comes inn very suddenly and stops suddenly too, it seams like I am listening to live music on many more albums now, also the tone is very nice, clear but with meat on the bone so to speak, can only get better with a better pre, by the way, don’t know if it is class A, but I can listen on much lower volume an still hear deep into the recordings, also when upping the volume the sound does not change, it just gets louder, just a wonderful  amp.