Preamp Gain issues with high efficiency speakers

You could check with Al F. at "mapletreeaudio.com", He hand makes absolutely transparent high quality switching and routing solutions, much better than the Chinese gear. He might be able to build attenuators into a a speaker router or a signal router, depending on whether you want to work from the source end or speaker end. Reasonable pricing for handmade custom gear.

I’m doing this from memory...but. The Hattor has the same Vc but you can add Op amps and have 0, 3 or 6 dB gain and the Hattor has a tube buffer option. Add that all up and about 4k if I remember correctly.

Anyway, I cheat JK. I only use my mains 100Hz on up. The subs get the rest. And the electronic crossover has attenuators.I can run mains with VC turned all the way up and adjust sub levels from there.

The Khozmo has 0 to 63 steps. Running the speakers at about 80 dB mid 20s on the Hattor. Blasting at 110 dB is 48 to 52. This can vary greatly by recording. The Pass doesn’t give up easily. I have Crites Type B speakers partially horn loaded)..  100dB efficiency(Cornwall clones)So that’s my mid fi layman’s explanation

@daledeee1 I also have an XA25 and have been looking at the Khozmo or Hattor, they seem to be the exact same with different branding for different markets. 

My source DAC is 2v output.

you have no bass issues?

Which speakers?

Thanks!

I bought hi eff speakers, 100 db.  

Digital volume on the Bluesound was terrible.

My old preamp didn't work

I have a Khozmo with Pass XA25.  It takes 1.25V to get full output on my amp.  Input sensitivity is 50k ohms.

I have no issues.  Khozmo can even accommodate different input sensitivities on your amp.  I gave all my specs to Arek and everything matches.  You can spend more for potentiometers but the Khozmo IS pretty transparent. I paid for upgraded resistors and I think it was still <$600.

I had a similar problem with ZU Omen Defs with a sper High gain amp (STA200). I placed a Schitt passive pre amp between my main pre and power amp and adjusted accordingly. Worked like a charm

https://www.schiit.com/products/sys

You could get something like a Pass B1 preamp, that's what I did on my high sensitivity system. A Pass B1 with Mundorf caps and TKD potentiometer sounds fantastic and is unity gain. Sounds much better at reasonable levels than my previous high gain preamp.

Speakers seem way too efficient for your set up.  Or get a tube power amp with just a few watts of power that will get along with your speakers. Cj has these types of amps.

Keep things simple 

This high efficiency setup seems a mismatch to the power amp. It seems like a low power SET would be everything the Zus would need and that your C-Js are better suited to a less efficient speaker.

I am a Luminous fan, and have much respect for Tim Stinson, the head honcho there. Properly matched with your amp and speakers, the Axiom Walker mod units are ime, the most transparent of them all. My best, MrD.

I can’t recommend the Hattor Audio preamp enough. It is the upscale version of the Khozmo preamps built by Arek Callas.

@vair68robert I considered this was an issue I was experiencing with the SYS. It made no sense that the completely passive pre still had little control of the Low gain range. 

I ordered a Schiit Kara and it works perfectly.

In passive mode, I am really able to dial in the full range of gain/volume from very very quiet to very loud. Even in 1x gain mode, I have good enough control over the gain range.

When I engage the 12db gain mode, it's still good enough to use. 

Unfortunately, it just doesn't sound as good as my CJ Pre-amp. Not that I expected it would. It is transparent and quiet, but it lack the warmth and musicality of the CJ. 

I am going to play around with other Passive Preamps, looking at the Khozmo and Luminous Audio Axion. 

Thank you everyone for your help!

As others have noted, you have too much system gain particularly with your speakers.  I have Devores, 93db claimed efficiency and a Zesto Bia 120, 60 watts per ch, 23db of gain and ended up going with a passive, resistor ladder setup so the pre is basically a volume control and source selector. 

It's possible that converting your amp to a 11X, i.e. triode and EL34s may be the ideal combination of less power and better quality sound.  I have an ARC CLassic 30 I use as back up to the Zesto.  Its input sesitivity is even higher than your CJ but less rated output and it matches up nicely in my system of passive pre and Devores.   Good luck!

Are you using the RCA outputs to run a sub or two?  I have a Bel Canto E1X pre/DAC that I use for as a Roon streamer and phono pre.  It also has sub outs where you can control the low pass start point. You can also add a main speaker high pass frequency.  I am using this to control the Torii and Vandersteen 1c and Vandersteen subs.  This arrangement allowed me to get around the need for RCA outputs on the Torii.

@karl_desch I currently have the SE34I.6 Zen Triode Integrated with all mods but considering upgrading to the Sarah. My issue with the Sarah is the dual volume controls and lack out outputs. 

I will let you know when the time comes, hopefully not too long. 

The Decware should match great with your speakers. I just picked up a used Torii MK IV and I'm having lots of fun. I am now looking for efficient speakers like the Zu. Please let us know how you like it. Are you still breaking in the Soul VI? Are you going to go for the new Sarah 300b?

-Karl

Good Luck with CJ 

I use a passive Gold Point preamp with my SS amp , 

in reading that the CJ volume control is to loud at 1 with 25 db preamp gain and  the Schitt allows you to go up to 7-8 with no gain it got me thinking .  

The 24 position control on the GP passive ( good reading on the web site ) increases volume by different db levels for the first 7 positions then at a steady 2 db's after that ,  using a tube phono preamp I play music from the 12 to 14 positions . So it's a [possibility that the Schitt does the same . If you look into a passive preamp look for one that from the beginning increases volume by 1/2 or 1 db , just a thought .

@vair68robert I was considering this, but I only have the stock Premier 11, not the 11a. I am unclear whether they can convert the 11 to the 11XS. I have asked CJ and will let you know. 

@atmasphere thank you for your reply. This was the same conclusion I came to as well. 

While I can listen perfectly with my system as it is, the only issue is the lack of usable volume control at the low end. Other than that, it sounds incredible. 

I have been on the Decware list for roughly 2 years and am about 50 from the top...so hopefully not too long. That was always the long term solution for these speakers. I am considering spending a bit more on the Decware amp to something higher in the line to be my end game tube amp. 

I also have a FW J2 on the way which will take care of my solid state needs I believe. I like to swap out tubes for SS every few months. 

Thank you for your help!

Read page 4 of the CJ manual ,  contact CJ and see if they can or WILL 

convert your 11-A 70 watt amp to the 11-XS 30 watt version .

@mstrshikadance As you've probably surmised by now, the problem isn't the preamps. Its a combination of way too much gain in the power amps and a typical digital source (your DAC) having way too much output.

Your amp reaches full power with less than 1 Volt. Your DAC makes 2 Volts... So you have to knock the signal level down quite a lot.

Normally with speakers as easy to drive as yours, the amp would have less power and certainly less gain. Your cj isn't all that powerful and the power would do OK on that speaker, but IMO/IME cj imbued the amp with too much gain. The gain is useful on less efficient speakers.

So in a nutshell its a mismatch.

The nice thing about speakers that are easy to drive is they tend to also be more dynamic as there is less thermal compression. This makes the presentation more lively and interesting. So if it were me, since all digital products put out 2 Volts single-ended, I would replace the amps with something with less gain and possibly less power. Less gain for sure. Otherwise you'll have to use attenuators and as you already noted, they impose their own sonic 'fingerprint'.

I tend to stay away from any preamplifiers using an ALPs pot. The attenuator is the heart and soul of a good preamp and can make a huge impact on the end result.

It would be absurd IMO to change the speakers, preamp, amp now.

When you tame the volume, your Preamp’s volume control can be used/set to it’s ’normally best’ most linear position rather than it’s minimum starting point. That is a benefit!

These units can be used ’up front’ to select up to 4 sources and control each volume into your preamp,

OR, between the Preamp and Amp

ALPS Remote Volume Control

https://www.aliexpress.us/item/3256804138895759.html?src=google&amp;aff_fcid=935f07f9b1c748348354370ac9bc6f3b-1703254601863-06284-UneMJZVf&amp;aff_fsk=UneMJZVf&amp;aff_platform=aaf&amp;sk=UneMJZVf&amp;aff_trace_key=935f07f9b1c748348354370ac9bc6f3b-1703254601863-06284-UneMJZVf&amp;terminal_id=9e131df15aa34acea8ffefb4ac5e99e0&amp;afSmartRedirect=y&amp;gatewayAdapt=glo2usa

My beloved Chase Remote Line Controller can be used similarly. None of my Audiophile Friends can EVER (over many years of blind tests) hear any difference whether it is in or out of signal path. It just does it’s thing to your advantage!

NOTE: MUST have the remote for the Chase unit, no controls on the unit.

The Chase has the added benefit of Automatically/Progressively implementing Fletcher Munson ’loudness’ (low volume bass boost), which would definitely be an advantage for you.

Default volume and higher: FM not in line

lower than default, FM begins, slight and more bit by bit as you lower the volume.

.................................................

Try the Chase, keep it, or I will buy it from you, never hurts to have a spare for me or a friend.

If you use it for a while, then solve it by other means, then if you want, I'll buy it then.

btw, I am using one Chase unit in my Office System simply for remote power of the system, then the Luxman Integrated (it's power switch left depressed) for everything else, including it's input selection; phono MM or MC; remote volume and mute.

Thank you all for the input. I guess all the niggles are what make this hobby so fun (and the music) ... endless tinkering, and trying new things. 

To be clear, with my current set up , I am completely happy with the sound...just find it difficult to cope with the fact that I am running my pre in the bottom 10th of it's range most of the time. I guess in the end it doesn't really matter. 

That being said, I have a couple pieces of gear on the way .... 😂

I can tell you other top linear tube audio , with top Lundahl transformer preamp 

call Mike at Audio Archon great preamp and several settings for gain actually 3 with a dip switch ,get the 6 sn7  tube , but also has 2 other tube  choices 4 tube total 

you tube has a-great review  breakdown and is superior to the CJ pre in several areas.

Unfortunately when you get a component on one end of the audio spectrum… like really efficient or inefficient… a really low power amp… etc. Then you end up committed to carefully swapping out supporting equipment. Then the next move is really hard to make… if it is to switch things out, then you are locked into the strategy.

Band-aides degrade sound… components not really built for your speakers degrade the sound. Your preamp and amp are world class stuff… but not ideal for your speakers.

OP, I would carefully think about the long-term. Would you like to be using these really high efficiency speakers or others like it in 20 years? If so, swap out your amp and maybe preamp to feed your speakers. If not, consider swapping the speaker for mainstream. Otherwise you can end up in a situation where just everything has to get swapped out.

While, it will depend on you. I would cut my losses and swap your speakers for those that sound right to you and are mainstream. But if the speakers are your cup of tea, then swap out your electronics. Lots of research will be required… otherwise you could easily choose an amp that suits your speakers but not the preamp… and maybe not the DAC… then you have a real mess.

This is a battle you just aren't going to win with your current gear.. The bandaids mentioned above will help but it doesn't sound like that's a route you want to go. 

I went down this road with la scalas, kt88 push pull amp, and Doge preamp. Tons of gain in the Doge. I tried everything and in the end it really comes down to the right equipment for the speakers. 

Knowing what I know now I would have went low power with low gain or no gain preamp. 

A solid SET amp with a high quality preamp that's low gain should get you there. Sayes or Radu amps/preamps have been fantastic in my systems. 

Good luck on the journey, and congrats on the new little one! 

i've also found that in-line attenuators (in my case, rothwells) had a subtle but noticeable affect on the sound, esp. at the high end. that said, i'd also be inclined to try a different passive pre. luminous audio, for example, will match your pre to the speaker efficiency, amp input impedance/sensitivity and source output voltage. i dunno what their return policy is, but they're pretty regular guys and make a good product. 

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5 way binding posts

I absolutely adore these speakers for a variety of reasons. 

1. I think they're beautiful. 

2. Midrage is flawless.

3. dynamics are unmatched

4. good bass heft

5. easy to drive (despite my ongoing gain issues)

I've been thinking of trying a set of Soul 6's for another room. how do you like the sound? 

It is a mystery why so much audiophile gear has too much gain, but often it does. Some of the newer gear has gain-ranging switches, for example the outstanding Benchmark AHB2 amp and many of the Class-D amps made with new Hypex and Purifi modules. But if you want the c-j sound, that won't help you. And if c-j still features only single-ended outputs, an adapter would be necessary to run a c-j preamp to one of those modern amps.

My source is a Pi2AES 2.0 running Ropiee over I2S to a Denafrips Pontus 2 DAC connected via rca to the preamp. 

As far as I'm aware, the Denafrips has no volume management and outputs 2.2v.

this is a pretty common DAC. 

I can't imagine I connected anything incorrectly when I swapped in the Schiit SYS, I just had one cable from dad to SYS, then one to the amp. 

I will try again and post results. I will also try and swap out the power amp and see what happens. 

All help has been greatly appreciated!

this has 5 way posts, independent L and R

Yes, I am thinking the voltage output of your source is  unusually high.

Happily, you have remote volume, AND remote balance for that Preamp, a desirable feature in any case, refine any volume control you add 

Niles Speaker Selector boxes are high quality

this one looks like standard component width

Something doesn’t add up. The input sensitivity of the Premier 11 is 950mV, which is high, but not as high as some CJ amps. Some are on the order of 500-600mV. I can see where 25 db of gain and 100 db speakers would pose a problem. But the Sys should have been much better in this regard.

For comparison, my system.

Amp input sensitivity = 1.5v

Speaker sensitivity = 104 db

Preamp = 0 db of gain (Hattor Audio passive).

I am able to run comfortably at 80% of the volume control of the Hattor most of the time. I can reach 90% when listening at very loud levels. Ideally, you’d want to be at the upper end of most preamps which is the least attenuation. In your situation with the Schiit passive pre I would think you should be at 80% or more of max volume.

I’m not saying you don’t know what you are talking about, but it seems strange that a passive pre doesn’t gel in your system. On paper it’s a perfect match.

PS

Another thought. What is the output of your source? Standard 2v digital output or something higher?

Are you able to return the Souls and acquire a suitable speaker ... something low in impedance, a bit less sensitive ...

There is a demo set of  SF Olympica Nova III.  Asking $6,000. Now that's Christmas!!

25 db of gain is way too much. If you don’t like using in line attenuators the only other option is a preamp with a lot less gain. BTW, CJ preamps are known for having preamps with high gain.

Thanks for the response, Viridian.

Would you surmise that this will be the case regardless of what pre I use?

Feels odd running my Cj Preamp at 1 out of 100, 99% of the time.