System Upgrade

Leben CS600; Harbeth Plus 5s; PS Audio with Bridge II linked via Blue Heaven USB; Chord Clearway interconnects and speaker cables (not bi-wired).

Sounds good but "flat" and I find myself having to turn up the volume almost halfway to get any "presence".

What am I missing, if anything?

Than you.
The volume control set at the upper range of the dial is better than having it at the lower range. If that is the only problem you are having I doubt you need to change anything!
Thank you.

Sorry, but what I meant is that whichever way, volume or not, the sound is flat and lacks that dynamism and presence, esp. with opera/classic. Basis the reviews for each of the products, my expectations were higher. Perhaps I am rigged wrongly - thought of buying an Aurender W20 or N10 but it seems I may not get that much more out of it. Others have told me your Leben is the problem?

Thanks again.
Others might be correct. You might want to drive those Harbeths with more than the 32 watts that the Leben provide!
How old are the tubes in your amp? Are they New production or NOS? Tubes sound flat and when they are starting to wear out. they also can sound thin and frequency extremes can start to decay. 

One other thing to consider is the Harbeth's are not that efficient.
Thank you.


Since I only recently acquired all the above, is there nothing else I can do? Preamp? Cables? Aurender or other?

Sorry to say but I doubt anything will work but more power amplification to get those Harbeths to sing!
Folks above are right. It’s probably a power amp issue due to inefficient Harbeths.  I think Leben pairs well with moderately efficient speakers (93dB and north). 
Thank you. Suggested amp pairing with the Harbeths?
Preferably valve but i may still be short on power.

Budget? Integrated or separates?
Hi Mdmdwyer- Yes the amp is a bit on the low side for this setup, but there is ONE thing you should check first.  The DSD DAC has an internal volume control.  Make SURE that you have that at 100% otherwise it does sound a bit dull and muffled.  Hopefully that is all this is.  Good Listening!!
Thank you. It i s @ 100%.

Integrated or Separates. Just took a look at  the Luxman 509X. Preferred budget is $5-$8k.
Excellent comments by the others. I would add, though, that if you already haven't you should try all four settings of the impedance selector switch that is on the rear panel of your amp.

When I hear someone refer to lack of "presence" I envision an under-emphasis of significant parts of the mid-range. And assuming that the impedance curve of your speakers is the same as or similar to what is depicted in Stereophile's measurements of the Super HL5plus, the speaker's impedance in critical parts of the mid-range is vastly higher than in other parts of the spectrum, and is also vastly higher than its 6 ohm nominal impedance.  Which suggests, for example, that the 6 ohm setting of your amp may very well not be optimal even though it corresponds to the speaker's specified nominal impedance.

Good luck.  Regards,
-- Al
You got mud Harbeths are warmly voiced loudspeakers, PS Warm, Cables warm.

Have you considered a cleaner more efficient loudspeaker?

How big is your room? Musical preferences? Do you play loud or moderate.

A less colored more full range more efficient loudspeaker would maxamize the rest of your investment and you would gain on all fronts. 

Can you go with a floorstander?

What part of the country are you?

Dave and Troy
Audio Doctor NJ
The amp is not the problem. I have one and it is holographic with the right setup. I have also owned shl5’s, they can sound very nice but dont seem to take full advantage of the Leben. Cables and source though are the likely problem. What is your room like?
A 30 day old Leben 600 will likely go at very close to full price
as they are made to order often times. If you unload the HL5+
you will take a $2k hit. I would get on the Harbeth owners forum
and get an answer straight from god's mouth.
Not sure which PS Audio, but trying different filters, along with the volume control is a thought.

For kicks, do you have a local guitar center?  go pick up one of the inexpensive or a couple of the inexpensive crown pro amps.  See what a crap-ton of power does for them.  You likely won't be keeping the crowns, but GC has a liberal return policy.   Just for kicks, see what some serious cheap, but powerful class D does with them.  Probably hard to find an amp more different than your Leben (seriously) a quick and dirty way to find out if it's an amp/power issue.  

If they still sound flat... think room, or frankly maybe they just aren't the speaker for you. 

(I'm not claiming the crowns will sound good... but it should/will address if a radically different amp changes the sound)
P.S. to my previous post:  Unless the manual or the manufacturer or dealer specifically indicates that it would be ok, I would not change the setting of the impedance switch on the rear of the amp while it is powered up.

-- Al
Sounds good but "flat"...

Coincidental word game, but Leben website proudly claims...

"FLAT and wide frequency response"

How old is that model? They also say it is "capable for future digital audio format such as SACD/HDCD."
More power will make a huge difference, IMO.  I use a 300 watt amp with the SHL5+.  Flat it is not.  
A hofer you have totally different gear. 

This gentlman has two really viable choices change the speakers or change the amp which then might necessitate other changes.

A pair of Focal  Sopras or Persona 3F are both more efficient have deeper bass and greater dynamics and the Personas would sound fantastic with the rest of his gear they are 92db efficient.

The Leben gear is excellent moving to more exciting speakers will perk up that system.  A 7db gain in efficiency is huge and his leben would be coasting not to mention the brighter sound of the Paradigms would complement his warm sounding components.

Peachtree Nova 300 will make them shine0

What tubes do you use with the  Leben CS600? Its first iterations used EL-34 or 6L6 tubes with a selector switch between eiher type.
Have you tried EL-34 tubes? Though, indeed, 32W is not a perfect match for Harbeths, with EL-34 tubes you would get a warmer and mellower sound.
Thank you All for your help. 

Re. Impedance it has always been running at 6. 

The Leben is the first iteration and I have not switched between the two options.

The Room is about 6 meters by 6 meters.

The PS Audio is the Directstream.

Listen moderately loud.

It seems like my only options are to change the amp or the speakers. I will also try the other modifs. Suggested and see what that brings.

Thanks again to All. 
I agree I have totally different gear. Nonetheless, the most obvious problem that any of us can diagnose on the internet is that his amp is underpowered for his speakers. You need a solid 80 watts for the SHL5+, 150 for larger rooms. As someone else suggested upthread, this can be easily tested without much cost or effort (order a 30 day trial or borrow an amp).

I suppose room placement is another easy and free thing to investigate, but whatever the case, the amp is underpowered. Speculating about warm voicings and such seems to me like medical diagnosis by text message.
Its the efficiency , MORE power . 
No its not just power if  you follow that for these speakers you should be able to get

86db  1w 1m
89db  2w 
92db  4w
95db  8w
98db  16w
101db 32w 

You might start to soft clip but unless you are not able to get a decent volume level the issue is not power.

When you have to raise the volume to hear detail and get any drive you have a lack of resolution.

This is not to say these are not all excellent components tbey are all voiced on the richer side of things.

Borrow a set of Nordost cables,  between the dac and a set of  Nordost speaker cables and then see how the system sounds. 

Dave and Troy
Audio Doctor NJ
I'm gonna go with 

a) manufacturer recommendation
b) peak transient power used in this video with the M40.1s as possible indication of power needs.

rather than kilobuck cables.  YMMV.
Very helpful, thank you. Will be test running with an Amp. At min. 150W, but more likely 300W. Possibly change some cables.
Ahofer, we have ATC SCM 19MK II an 85db efficient loudspeaker, we play them very well with an Naim Uniti Atom a 40 watt amplifer. The Naim is punchy and warm so it adds life to the ATC which tend to sound clean and the Naim’s amplifier stage creates a punchy sound with the ATC. So we have seen first hand that a low powered amplifier can drive and derive excellent sound from an inefficient set of loudspeakers.

We have no issues getting them to sound good and play loud enough in a decent sized room 18 by 14 with a 10 foot ceiling.

This gentleman allready has expensive cables, dac, and amplifier.

The issue is what we call mud: warm speakers, warm digital, warm cabling, this all creates a sound which isn’t involving and requires you to raise the volume to hear details.

The corollary is sizzle systems: bright speakers, bright amp, bright source, bright cabling = fatiguing sound, over sibillent sound.

He needs to rebalance the system by adding in products which add more detail or sparkle to the sound.

Our suggestion is to borrow two cables from the Cable Company, a set of interconnects and a set of speaker cables, willing to bet dollars to donuts without changing anything else just changing the cabling will bring the system back into some sense of balance.

We are not saying that more power won’t be a good thing, more power is never a bad thing, howerver, we have seen many 85-87db loudspeakers sound fantastic with a low powered amplifier and still get to both a decent volume level and get great sound until you run out of steam and the amplifier distorts.

When you have to turn up the volume to hear detail means details are being lost, we have systems that sound fantastic at lower volume levels, we look for high resolution loudspeakers such as KEF, or Paradigm, or Focal, or others, that preserve all the details in the music and then match those cleaner speakers with warmer electronics.

It is all about system synergy.

The Leben is a terrific amplifier if this gentleman moved into a more efficient loudspeaker he would be in win win scenario.

His loudspeakers are not efficient, and they don’t go that low in terms of bass, for the same real estate as a stand mount he could move into a floor stander with both greater efficiency and more deep bass.

Harbeth is one of those love hate brands, we are personally not fans way too colored, and although they have stunning cabinetry, for the price of $7k plus a set of stands there are tons of great floorstanding loudspeakers that will offer more overall sound for the dollar.

Harbeth does have a very musical sound and can be very engaging, which is their draw, so this gentleman has a few choices;

1: Change amplifier: now he has to find an amplifier which will work well with his other choices and this amplifier may not have the midrange magic and soundstaging that a good tube amplifer has.

2: Change loudspeakers: audition a set of more efficient 90-92+ efficient loudspeakers that work well with a 32 watt tube amplifier, here again you have the possibility of gaining both greater efficiency you may also gain a loudspeaker which has greater dynamic range, more bass and may have a more lifelike sound.

3: Change cabling to a brighter sounding set of cables which will help rebalance the sound by adding more detail and clarity, brighter sounding cabling is AQ, Nordost. Netural Wireworld, Wamer Cardas, Transparent, MIT, Kubala, Shunyata. He has warm sounding cables, he need to try brighter more detailed one hence the AQ or Nordost recommendation.

We have heard systems with plenty of power that played loud and still had no detail, if you obsure information playing louder doesn’t fix that problem.

If you are going to demo amplifiers you don’t need necessarily 300 watts you need an amplifier which will drive those speakers well and provide the sound quality you are looking for. Please test our suggestion by borrowing some cables and then seeing if you get the detail back before changing the amplifier. If the cabling does the trick you are good to go. Then if you still want more then you should try a different amplifier but also consider if the Harbeths are really the best speakers for your application.

Good luck OP.

Dave and Troy
Audio Doctor NJ

Let me reiterate, the Leben amp and these speakers mate well and I have heard this exact combination sound exceptional.

a few things you might try:

Do you have great headphones? Listen through the headphone port on the Leben to ensure the sound quality is terrific. Report back to the group because this would isolate your issues between the amp and the speakers if it sounds great. If it doesnt sound great, the problem is server, network or dac to amp for the issues. If using roon, check your settings and try disabling sample rate conversion and/or dsp. Are you using a good ethernet cable?

If nothing then try setting your Leben on the 8 ohm setting.

A wildcard to check is your power. What kind of conditioner are you plugged into? Maybe plug the components directly into the wall or even a different outlet. You may be being starved for ac.

Another wildcard. How are you plugged into the Harbeths? On those speakers, there are two posts on each speaker for the positive/negative for low frequencies and the same for high frequencies. Are you using quality jumpers between the respective lf/hf pos/neg terminals? Is it tight? Are you certain you have the positive and negative properly wired in phase? Something else that may work is to plug the negative cable for each speaker to the low frequency negative and plug the positive cable into the high frequency positive.

Do you have any other cables to try. While the Harbeth SHL5’s arent the best speaker in the Harbeth line, there is a synergy with Harbeth and Leben. While the spl of this combo may fail to check your boxes, it should be a combo with some magic that it doesnt sound like you are hearing. Best wishes and good luck.

The issue is what we call mud: warm speakers, warm digital, warm cabling, this all creates a sound which isn’t involving and requires you to raise the volume to hear details.

The corollary is sizzle systems: bright speakers, bright amp, bright source, bright cabling = fatiguing sound, over sibillent sound.

He needs to rebalance the system by adding in products which add more detail or sparkle to the sound.
I don't think we have a consensus definition of "mud" (or "magic" for that matter).  As I've said before, I think cables and amps are incredibly expensive tone controls and shouldn't be used as such.  But we just differ on that approach.

I have an off topic but related question I'll pose separately.


Something else occurred to me and its probably an obvious thing that you have already checked but you may be experiencing one speaker out of phase.

Please double check to ensure you have your speaker cables wired correctly on the back of the Leben. If you are looking at the amp from the rear, unlike many amplifiers where the speaker taps are "mirror" image, the Leben alternates. So, from looking at it from L to R you will have the right channel positive tap, then the right channel negative tap, then the left channel positive tap and then the left channel negative tap.

You have probably already checked it but its worth a try. Best wishes.
Ahofer cables and amps are incredible tone controls, so is adding spices to foods, adding more or unusual ingredients to a well known dish to alter the flavor to taste.

Came up with the Coffe Drinkers School of Audiology many years ago.

Take a great high end coffe bean, crystal clear filtered water, and a good coffee machine now make and serve your coffee.

Coffee drinker One: Total neuturalilty camp: Pure, hot coffee no milk, no sugar = the detail guy wants to hear everything no coloration great recordings sound great, bad recordings sound horrible.

Other end of the spectrum: Coffee Drinker Two:  The sweet Coffee guy or the polar opposite of Coffee drinker One:

Take 1/4 cup of cream, six table spoons of sugar, yes the high end coffee is still there you just can’t taste it, the flavor is predominantly rich, mellow, sweet, but very little coffee flavor, a new creation. This listener craves the ability to never have to have any listener fatique everything and every recording sounds good, this kind of listener likes a rich tube amplifier, warm loudspeakers, lot of vinyl, the system sound lovely but doesn’t sound like real music.

Middle Ground Coffee Drinker Three: Standard cup with the bite removed: the slightly toned down version of neutral. This listener strives for a system that sounds real but the top end is a bit warmer. The Coffee analog is a touch of milk or cream with a bit of sugar. This listener craves a realistic listening experience with a just a bit of euponic coloration. Cymbols crash, high hats have bit but not too much.

Now you have three points on the curve, hyper detailed on one extreme, on the other side hyper warm on the other end, and the more middle ground, neutral with a bit of softening. Of course there are more points on the scale but these are given to illustrate a point of reference. 

Audio is like cooking we start with a great set of speakers as the speaker determines the kind of amplifier and the power required, we demo many in our floor: Kef, Paradigm, ATC, Quad, Golden Ear, etc, then we demo different electronics, first we start with solid state inegrateds, then separates, then tubes or possibly hybrid systems with a tube preamp with a solid state power amplifier,  then we demo different digital front ends.

So yes tube amplifiers sound different then solid state, some solid state amplifiers are bright, some are warm, some cables are bright, some neutral some are warm, same with digitial.

A good system requires carefull matching and balancing all of the parts, which is why for this gentleman we said start with a simple switch to brighter cleaner sounding interconnects, which are easy to ship and demo.

Dave and Troy
Audio Doctor NJ

Thank you All for being so helpful and responsive and offering up various solutions. It is going to take me a while to check everything but once i do, i will report back.
OP please try to borrow a few sets of interconnects and some speaker cables and just change those first and see what you think.

Another question are you using stock power cables and do you have a power conditioner. Power cables make a very large difference in the sound of a system.

The other question is are you working with a dealer and if so what was your dealers response to all of this?

Dave and Troy
Audio Doctor NJ

With that super tweeter, the HL5 is the least warmly voiced of the Harbeth range.  Don't be rushed into a speaker change you don't need.

It may be the amp, and your room may have something to do with it as well.

Two left ears ever listen to a Murata supertweeter?

If a speaker needs a super tweeter it is not going to be voiced on the lively side now is it?
Everyone take a moment, the OP needs to troubleshoot his system.

 There are too many people using his exact amp/speaker combo reporting exceptional sound.
Who are the too many people using his exact amp speaker combo?
The reason I bought this amp and speakers was for the one mentioned just now by ghasley. Problem is, when I wired it up with my current setup I ran into the “flat” problem and wondered if I missed something. When playing Prokofiev’s Romeo and Juliet Decca recording it is stunningly absent. That said I intend to try some of the suggestions above and will report back. Thank you. 
@mdmdwyer, Prokofiev’s "Romeo and Juliet" is of course a work having exceptionally wide dynamic range. And although I don’t have a recording of it on Decca, given that it is on that label I would suspect it has been well engineered, meaning without large amounts of dynamic compression. **If** the "flatness" occurs mainly on recordings like that one which have particularly wide dynamic ranges it would seem to suggest that lack of power may indeed be the root cause of the problem.

BTW, I have the Leinsdorf/LA Philharmonic recording of Prokofiev’s "Romeo and Juliet" that was done by Sheffield Lab, on their direct-to-disc LP and also on CD. Some time ago, out of curiosity, I examined the signal waveforms that are on the CD using a professional audio editing program, and determined that it has a dynamic range (the difference in volume between the loudest notes and the softest notes) of about 55 db, which is simply incredible.

Good luck. Regards,
-- Al


Jeff Day for one. Many more use the amp with other speakers, floorstanding or bookshelf/standmount, high sensitivity or medium sensitivity. The Leben is exceptional. While I also like Harbeth alot, the SHL5 isnt going to play 120db BUT, it should sound three dimensional, layered, etc. The best I’ve heard the SHL5 sound was connected to Leben. Also @donvito you can google Leben and Harbeth and there are many variations on the theme.

I am certain there is a mismatch, a misconnect, a malfunction or a software/digital issue. For once on this site, it isnt the equipment unless there is a need for a repair.
No problems with the headphones test - quite the contrary. 

Runs better at 8 impedance vs. 6.

Using power cables provided with original units and a cheap 6 way Westinghouse adapter. 

Ethernet cable is a Supra Cat 8 from Sweden.

Looking into demoing a few amps and cables.

And yes, I am using Roon to run Qobuz.

Did you have the opportunity to double check your speaker cable connections to the Leben as I described in the post above? Triple check that your positive and negative speaker cables correspond to the non-traditional Leben alternating layout. What about the connections to the Harbeths as I described earlier? Since the headphone output uses the same amp output circuitry as the speaker taps and it sounded nice, then I believe your problem may be from the back of your Leben to the speakers.

Additionally, unplug your Leben from the Westinghouse adapter NOW and plug it directly into a wall outlet and listen for changes. You may be current limited through the adapter. Keep after it, you purchased great gear and great sound awaits.
Thanks so much. Speaker cable connections are correct, same with the Harbeths. Leben plugged direct into the wall.

Also changed the selector switches, cathode down and plate voltage up. 

We certainly have improvement. 

Thanks again. 
But the moment you challenge it - Choirs, organ music...dial halfway and it is struggling. I think, per earlier posts, power/drive is lacking. 

Whoa. When you changed the selector switches, were they incorrectly set for the specific tube type installed? The switches should be set for the specific output tube only. Did you buy your Leben new?

Take the Leben with you to your Harbeth dealer and drop it into their system and see what you hear. Its also a good practice to be able to compare against other amp offerings the dealer may have so you can get a proper match to your desired speakers. Obviously something isnt meshing, how unfortunate. Best of luck on getting what you are after.