Preamps


I'm not unhappy with the Jeff Rowland Corus preamp,  but I don't know what I don't know. I'm currently looking for a solid state preamp with HT bypass to compare to my Jeff Rowland Corus preamp. I would like suggestions below $15K new list price to listen to. I have a Jeff Rowland 625 S2 amplifier, Antipodes DS GT music server and Chord Dave DAC. 
ricred1
What do you feel strongly about the Corus?

Would be real nice to hear from your experience. Thank you

(I don’t like Rowland, for the record)
I've compared my JR 625 S2 amplifier to several other amplifiers in my system and I prefer the 625 S2. I haven't compared the Corus to any other preamp; therefore I don't know, what I don't know. Unless I compare the Corus to other similarly priced preamps, I simply don't know the strengths or weaknesses it has. For what it's worth, many people have told me the Corus is my weak link and now I'm curious to hear other preamps.

As far as you not liking Rowland...there are no absolutes in audio, only preferences. 
my experience with a 625/aeris/corus set up a few years ago was that in comparison to aeris direct the corus was softer and frankly boring. on the other hand the aeris was too hot. end result is i sold it all for better or worse. things change so it’s hard to compare a few years later but i now have a luxman c-900u plus m-900u and boring w current setup has never crossed my mind. but.. different speakers cables etc. i do i know enough to say that i’m pretty sure that the corus is not a special piece except perhaps with the optional upgraded 9k power supply. fwiw
OP: Do you want an active solid state preamp? Are you open to passive preamps?
Schiit Freya. https://www.schiit.com/products/freya

3 preamps in one S/S, Tube, Passive.
best mechanical volume control 128 position relay
remote control
5 inputs 2 outputs
xlr or se
low/zero gain so it uses most/all of the source signal, instead of shunting a lot of it to ground like most active pre's do, which gives lower noise.

Cheers George
Have you tried using the volume on the Dave and skipping the pre?  It's an amazing piece of equipment and should do well.
elevick,


When I first received the Dave I tried it straight into the amp and preferred music with the preamp inserted.
Since you likely are never gaining your input source voltages, it doesn’t really matter if the preamp is active or not. 
  
How are you unhappy if you stated you don’t know what you don’t know? Try not using the pre-amp and drive your amp directly with the Dave (keep music at max level and turn down the level on the Dave. Compare that with using a preamp. 
 
A preamp is never improving the sound quality, so unless you need amplification or a different output impedance, a preamp can only harm the sound. If you get a good enough preamp, then any harm is negligible. So, it’s main duties are simply volume control and source switching. 
 
I am unaware if the Dave takes care of intersample overs; if not, it’s best to lower the volume on it to -3dB. 
 
So again, try comparing using the Dave directly against using your preamp, unless there is some crazy issue with output impedance, a preamp added will never sound better (unless the volume control on the DAC/source is poorly done), so directly from the Dave should sound the best possible.
Ayre KX-R
a superb SS preamp from a now departed genius
... and a fanatical implementation of volume control

Definitely consider and audition the GamuT D3i. We used it last year at AXPONA and will again this year, along with their D200i mono amps. Incredible combined natural sound and resolution. It is available with a phono stage. PF and other reviews available online.
Note: the GamuT's USA distributor also distributes our product and is a personal friend. I have no commercial interest in/with the GamuT products.Good luck with your search.
When I first received the Dave I tried it straight into the amp and preferred music with the preamp inserted.

Yes, I can see that. But first you have to make sure you weren't "bit stripping" if the volume on the Dave was below 75% of full you could have been losing "bits" (lowering the resolution from 16bit to 14 to 12 ect the lower you go below 75%).
  
If it wasn't "bit stripping"  then yes going direct can sound absolutely stunning with unmatched transparency and dynamics with the good to best recordings, but then almost unlistenable with the bad recordings, it gives you everything warts and all and pulls no punches.

A preamp will be a a bit of an equalizer pulling back a little on the good/best recordings, and making the bad one a bit easier to listen to.
It all depends if your prepared to cull some of those bad recordings for the sake of hearing the good ones at their very best. 

Cheers George  
Thanks to everyone for responding. I will look into a couple of the recommendations. I actually need a preamp with HT bypass, so going direct isn't an option anymore.
Another nod for Ayre. I also recommend T+A P3000HV. 

There is a demo T+A on Agon, 

https://www.audiogon.com/listings/lis8hd59-t-a-elektroakustik-p3000hv-available-in-titanium-and-silv...

And this is hot off the press for you to consider, 

https://www.stereophile.com/content/emm-labs-dv2-da-processor

Should you choose to look into a Tube pre, ARC Ref6 should be on your list. I believe it will be a killer pre for your 625 S2 amp. 
@georgehifi said: ...going direct can sound absolutely stunning with unmatched transparency and dynamics with the good to best recordings, but then almost unlistenable with the bad recordings,
---
Precisely my experience with a wonderful passive I auditioned that was much cleaner than the DAC volume control.  There were just too many recording where I really didn't want the band in the room because the mastering sucked.  A real conundrum.  Can I handle the truth? I'm back to that loosy-goosy search for a "sweet sounding" linestage.


It's my understanding that ARC preamps have issues when using a subwoofer and I have a JL Audio F112 v2 sub.
I think step #1 is to identify what you think the weaknesses of the Rowland are, and /or what you want further improved.
Honestly with out that its a crap shoot/
G

There were just too many recording where I really didn’t want the band in the room because the mastering sucked.

It shouldn’t be too hard to set the system up so when good recordings are played it goes source direct to poweramp, and you use the sources volume control.
But when bad recordings are played the source goes through an active preamp using it volume control that de-focuses them and makes them more listenable.

What’s needed is a source/preamp switcher to the poweramp/s.

Source direct outputs have to be disconnected from the amp inputs, and re-directed to the preamp inputs, and the preamp outputs then connected to the amps inputs. All done powered up with just one flick of a switch without any clicks, pops or bangs.

Cheers George
@itsjustme Very good advice.  Not figuring that out probably accounts for a majority of the constant component switching audiophiles undertake.  Having said that, it's something hard to do without experience.
Virtually all tube preamps are ‘not’ designed to drive a main and secondary amp(subwoofer). ARC addresses this on their website. I have a friend that has looked far and wide for for a duo amp driving tube pre and i believe vtl turned up as satisfactory but at a price. of course
itsjustme,

"I think step #1 is to identify what you think the weaknesses of the Rowland are, and /or what you want further improved.
Honestly with out that its a crap shoot/"

I submit many people on Audiogon, not all, make comments about components that they haven't actually listened to or heard in a familiar system. Part of my journey is knowledge based. It isn't about a perceived weakness in the Corus, but how does the Jeff Rowland Corus preamp compare to similarly priced preamps in the context of my system. I hear a lot of people say Rowland preamps aren't good. I recently went through a similar journey with my speakers and DAC. After listening to several speakers and DACs I'm completely satisfied with my speakers and DAC. I would be a fool to just sell my Corus without listening to other preamps. I will have the Esoteric C-02X preamp on Wednesday and I plan on listening to the Emm Labs preamp. For better or worse I'll be sure to post my findings. 
Another Ayre KX-R recommendation.  They are more than your target price, but you can sometimes find them on audiogon for sale.
Ricred1:  I know something about the corus and 625 amp as I owned them and should have kept them.  If I had just ponied up and bought the uber power supply I think I’d be miles ahead of trading and selling to TRY to find something better. I would beg borrow or steal to get to try that power supply in my home. I bet jeff would help if you call him directly. It’s absolutely worth the effort imho. you’d then have something very special.
4425,

I appreciate your concern. Unless I come into a lot of money I'm definitely not replacing my JR 625 S2. The verdict is still out on the Corus and it really depends on what I hear relative to the cost of changing preamps. I may hear some preamps that are different, but not worth changing from the Corus.
ricred1, 4425,

I just contacted Audio Research about your statement that the ARC preamps having issues with subwoofers, and they said there would be no problem.
Where did you get that info?

ozzy
ozzy
I just contacted Audio Research about your statement that the ARC preamps having issues with subwoofers
ricred1 OP
I can understand "they" may have, as AR pre’s being tube are output capacitor coupled, are used to seeing tube poweramps of up to 100kohm input, and many subs have a very low input impedance 10kohm
  
You need a big output coupling cap if you want to get down flat to 20hz with 10kohm input, and they may not be big enough.


And I just looked your sub is 10kohm input!!


Cheers George
ozzy,

AR told me that their preamps have two inputs so it should have no problem driving an amplifier and subwoofer, but based on the low input impedance of the subwoofer many say it isn't optimal from a technical standpoint. The guy I talked to at AR agreed that it may not be optimal. 
georgehifi, ricred1,

Thanks for the information. But since the subs are self powered I don't see how the preamp output impedance can affect the sub. Also, the JL subs have a mic/calibration system, that would seem to me it would compensate for any possible low bass rolloff. Now, if having the sub connected affected the performance of the main amps then I would be concerned.

ozzy
But since the subs are self powered I don't see how the preamp output impedance can affect the sub.


The AR preamp with output coupling cap, has to drive not only your main amp input impedance, but also the 10kohm of your subs amp even though there are 2 outputs, and this could be the problem, the output cap in the AR  "may" not be big enough as explained in my last post, and cause a premature rolloff of the low frequencies, so the sub may not go down low enough.

Cheers George 
ARC has a fact sheet on their website expressing concern about the tube preamps driving a main amp plus sub. it’s in black and white unless they pulled it. it killed a ref 6 deal for me.,
just looked at arc site. article called the thorny issue of impedance. it’s located in a ‘tips’ section.

georgehifi, ricred1,4425,

It was very hard to find on the AR website but this is the link. Odd though that the AR rep didn’t know this...
This also kills my plans for using a tube preamp.
http://www.audioresearch.com/ContentsFiles/The%20Thorny%20Math%20of%20Impedance(0).pdf
i’m told that vtl tube pres can handle the situation. i fixed it by buying an awesome tube amp to be used w a great SS preamp. IMHO this more than gets you to full tube sound. the tube amp is the last thing the speaker sees. and what a choice of great SS preamps out there. what a great hobby!
Georgehifi is wrong about the Schiit Freya...it has five inputs and THREE OUTPUTS...2 single ended and one balanced. What a stunningly horrible misstatement, rendering me horrified and utterly saddened, reduced to a mere shell of a man...*sniff*...

Georgehifi is wrong about the Schiit Freya...it has five inputs and THREE OUTPUTS...2 single ended and one balanced. What a stunningly horrible misstatement, rendering me horrified and utterly saddened, reduced to a mere shell of a man...*sniff*...
https://i.stack.imgur.com/4RK6O.jpg

Shattered!!!
So, before I do anything with equipment I decided to invest in improving my room. I currently have GIK Acoustics, but decided to contact Vicoustic Resources. I already paid them to provide recommendations based on the information I sent to them. I will go through my local dealer to purchase the recommended room treatment and have it installed.
ozzy... luxman c900u but would have been happy w ML 523. Amp ARC 75se. great match but then i bought the lux m900u amp. have both but going to have to give up Ref 75se. what a great amp. a plethora of riches
Is Ayre out of business? Every time I try to call, NO-ONE answers the phone! Its all voice mail!

ozzy
I don’t think Ayre is out of business,  I exchanged a few emails with Gary about a week ago and they just updated their instagram today.  Try posting on their Facebook page.  
@georgehifi Freya is a great piece of equipment but a horrible tube amp. I have a collection of best 6SN7 ever made. Noiseless in my other preamps. Same tubes in Freya make noise. Same with microphonics. The thing somehow picks up all vibration in the room and directly transfers it to tubes. Great JFET buffer. I use it between sources and studio monitors, but as  tube preamp, it's worthless.

@ricred1 Long time ago I quite caring about HT bypass on preamps with a little box from Luxma, the AS4 RCA selector between preamp/processor and the AMP. About 100 bucks shipped from Japan. About as transparent as components can be. Probably quieter than a relay in a preamp. Now, you do have to get up and press a button. Save yourself some money, buy a Don Sachs preamp for $3K with all the options and have him install a large second coupling cap for subwoofer. I have both his preamp and a LS28 from ARC and both are about as good as it gets.

wolf_garcia do you agree with this you have one???
"@georgehifi Freya is a great piece of equipment but a horrible tube amp. I have a collection of best 6SN7 ever made. Noiseless in my other preamps. Same tubes in Freya make noise. Same with microphonics. The thing somehow picks up all vibration in the room and directly transfers it to tubes. Great JFET buffer. I use it between sources and studio monitors, but as tube preamp, it’s worthless."

Cheers George
"Is Ayre out of business? Every time I try to call, NO-ONE answers the phone! Its all voice mail!

ozzy"

They moved and had somewhat of a nightmare dealing with the phone company and getting their calls forwarded to the new location.
Hope this helps.
Nonsense. I also have a large collection of 6SN7GTBs and they're dead quiet in my Freya, and the thing is as quiet as any SS preamp I've owned over the decades...or quieter. I guess I got lucky! I have a Loki EQ in the path and it's usually off, but a good test for noise is to crank the highs in the Loki and put my ear right at the tweeter horn on one of the Heresy IIIs...no tube noise at all, and really a very quiet, virtually noiseless preamp. I'll note the obvious that microphonic tubes are THE TUBES, not the amp, and to claim a preamp itself is responsible for tube noise issues from microphonics is strange indeed. I toss noisy tubes in the bin, so to speak.