Need some Tube and Class A SS Suggestions

Just got my Supratek Cabernet today, is playing now with the Belles SA30 class A power amp.
Sounds delicious.

@shahram 

I ended up with an Exposure 3010s2d for my Spendor D7's. 

Despite the modest price it is a substantial upgrade over a Hegel H80. I hear a powerful bass for the first time from these speakers, can pinpoint instruments in space more clearly and tone is improved. Really the improvements are across the board. When listening to Whale & Wasp, I hear a resonance from the violin that I've never experienced from reproduced music. Of course there is better gear out there, but hearing this was quite beautiful, and fuel to pursue this hobby. 

Upstream I'm using a MHDT Orchid which uses a tube buffer. I do like having a tube somewhere in the chain for these speakers. I recommend the 6922/ECC83 adapter mentioned in other threads for this DAC.

Swapping speaker cables DNM -> Raven, adding Gaia III's and changing rooms have all been beneficial. I've had these Spendors for three years now, and continue to appreciate them with every tube, component, or cable change. 

Class A ?  Pass Labs without a doubt.  Nothing will come close unless you go to ridiculously sized (and priced) amps like Boulder or Dagostino.

@shahram   

Balanced outputs are not a major consideration. More of a nice to have.

When considering a new component, it's nice when the design elements help give you the most flexibility in the future and get the most from your other existing gear - it just reduces the risk of wishing you had considered your criteria more thoroughly before buying.

For instance when I bought my Pass XA30.8 (fully balanced circuit) I did so with full consideration that my existing preamp used a transformer- coupled Class A1 balanced triode design.  It's just one of those things where if the price isn't any higher and you like the sound at least as much as your other choices it help cinch the deal because you're getting more design synergy for your buck.  At least that's the way I look at it.

One of the amps I'm considering doesn't have a balanced input, which is the Pass Labs XA25.

@atmasphere 

Balanced outputs are not a major consideration. More of a nice to have.

@s

Two of those preamp have balanced outputs. Are you planning an amplifier with a balanced input?

And another Preamp enters the ring. The Linear Tube Audio microZOTL Preamplifier. The preamps I am seriously now considering are:

• Rogue Audio RP-7
• Backert Labs Rhumba 1.3
• Linear Tube Audio microZOTL

All these preamps have a few things in the common. They look attractive and kind of mid century modern. They are not gigantic. And they are partially or fully tube based. One of the main reasons I don't want to consider brands like BAT and Audio Research is I just don't like how they look. BAT especially.

@georgehifi 

I take your point there. Someone on another message board mentioned how they heard D7s with a Primaluna Dialogue HP at a dealer. They ended up buying the D7 as a result! So i think one thing that will trump what *might* be an issue with measurements is just listening. Hopefully I can figure out a way to do that.

See how the Prima Luna’s output transformer has less instability ringing (peaking) from 10khz up when it is loaded down more and more.(green trace)
Prima Luna
https://www.stereophile.com/images/1214PLDPIfig01.jpg

But the D7’s impedance goes higher and higher from 7khz so the peaking will get worse and worse on the Prima Luna.
It would be far better for the D7’s impedance to go down instead of up, to keep the ringing peak down.
Spendor D7
https://www.stereophile.com/images/0415-SD7fig1.jpg

Cheers George

@1markr 

The sheer number of permutations there are for a pre and power amp combo is staggering. At least you've taken some uncertainty out of one of the combos i'm leaning toward. Thanks for chiming in!

@shahram 

If you are thinking of matching up the Rhumba with a Pass XA25, let me attest that the combination is fantastic! I have the 1.2 with an XA25, and love it!!

@shahram   The Pass is better from top to bottom compared to the Cary.  There is simply more weight, texture, and saturation across the entire frequency range.  There's a blacker background and hence more dynamic range.  Plus the soundstage is much bigger and the imaging is better defined.

The Backert Labs Rhumba 1.3 has joined the conversation for the preamp. I e-mailed the company and got a prompt reply, so good start there.

Very sexy looking too!
https://backertlabs.com/rhumba-1-3-preamp/

@kren0006

You are right about the break in. It is happening slowly for sure, but I am hearing the difference as time goes by.

I have been looking at ARC as well. The ARC LS28 preamp is definitely interesting, but a bit pricy at around $4800 on the used market. 

@three_easy_payements

Thanks for the feedback.

How do you like the midrange and treble of the D7s with the Pass Labs vs. the Cary tube amp?

My volume knob rarely goes past 10am with this amp with a digital source. Vinyl can push it to around 11am.

I own D7’s and for last year have driven with Audio Research DSI200 SS integrated amp. 200w into 8 ohms. Sounds pretty magical to me. You can find the ARC used usually around $2.5k


Note that they D7’s take a few hundred hours to break in, but when they do they are amazing. It’s that LPZ tweeter that sets the D line apart from the lower Spendor lines. Just fantastic. 
I like it so much I have the D1’s in my secondary system and the older (non-LPZ) SA1’s in my third system. No comparison D1>>>SA1 to my ears. 

@shahram

What tube amp did you use previously?

I had a Cary CAD120S MKii, rated 60w in triode and 120w in ultralinear. Even in UL mode it didn’t come close to driving the D7’s like the XA30.8 can.

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?

When listening to a digital source (streaming in my case) I never turn it up past 10-11 oclock on the dial. That pushes the level up to 95dB or so listening 9 feet away. And the preamp I’m using only provides 10dB of gain. When listening to vinyl I rarely go above 12 oclock.

I’d say most of my listening is around 80-85dB and I’m somewhere between 9-11 oclock usually depending on source.

@photomax

Ah yes - D9s. I knew that!

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.

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...

@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.

@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?

@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. 

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

I just ordered a Pass Labs XA30.8 to go with my Spendor D9s. Will be selling my Bryston 4BSST-2 amp...

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!

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

@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.

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.

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.

@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.

The Rogue Audio RP-5 preamp (or better yet RP-7) and Stereo100 amplifier are a stunningly magical combination.  

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.

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...

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.

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.)

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"

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!

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. 

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 :(

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.

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 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!

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...

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.

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.

@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.

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.     

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.