Need a line stage preamp


My Acurus LS11 line stage preamp (early 90’s vintage) seems on its way out.  Or I think so.  I’m noticing that the right channel doesn’t seem as “peppy” as the left channel.  I’ve deduced this through various tests and I’m left with my diagnosis.

that being said, I like this little preamp, and I could send it somewhere to be fixed. On the other hand, I could also buy a new or used preamp, but the “law” has laid down the law and she’s nixing anymore serious spending. 
FYI, I use the preamp to run an ARC Classic 60 amp.

My budget is only $500, so unless I can find an equivalent pre I’ll be forced fix it. The question is who does good electronic testing and repair or can anyone suggest an equivalent component?
last_lemming
If you don't require the balance control or the tape loop your LS11 provides, you may want to consider the following very law-abiding model, costing $450 new:

http://www.divertech.com/asllineone.html

Spec-wise it appears to be a fine match for your Classic 60 amp.  And you could have some fun rolling its single 12AU7 tube.

Some years ago I temporarily used its predecessor model, the Line One, in my main system while my main preamp was down.  It sounded remarkably good, even with its stock tube, which I attribute mainly to the simplicity of its circuitry.

Good luck.  Regards,
-- Al
 
Not a lot I know of personally for $500 that are worthy of your amp, as it’s too bad you can’t stretch a little more as you have a nice amp. If I was looking for something in your budget I’d research the Schiit Saga+, if it is compatible with your Classic 60. I would be surprised if the little Schiit doesn’t easily keep up with your Acurus. Years ago I worked at store that sold Acurus along with Aragon and the Acurus was pretty good for the money, but that being said if you can find the big brother, Aragon Aurum w/Ingot power supply that would be a big step up and just checking online on another similar site there’s one out there for sale close to your budget.
Maybe a used ARC LS3. I also have a Saga, but you probably want something with some gain.
Me personally,at your budget,I would only purchase used. You'd get more bang for your buck.
Right now the Schiit Freya S looks interesting.  
Keep in mind that the input impedance of the Freya S is only 10K, which is too low to be optimal with many tube-based source components.

Also, as Coach pointed out the two versions of the Saga do not provide any gain, while also having a 10K input impedance.  Your LS11, btw, provides 18.8 db of gain, so with either version of the Saga you would be operating the volume control at far higher settings, while possibly even running out of range on the control especially if you have a phono-based source.

The Antique Sound Lab line stage I linked to, btw, provides gain of about 22 db, just a bit higher than the gain of your LS11, while having an input impedance of 100K.

Regards,
-- Al

Al,

the output impedance (single ended) is 75 ohms and the input impedance on my amp is 100k. 
I thought the ratio had to be min 1:10?
@last_lemming

Note that I was referring to the 10K **input impedance** of the Schiit models that were mentioned, and the possible incompatibility that might cause with the output impedances of **source components** (especially tube-based source components), not with your amp.

Regards,
-- Al

I’m a bit confused and maybe just dont understand, can you explain what the 10k input impedance is all about? How it affects things. I would not be using the Freya in passive mode but active.

my source components are a Parasound JC3+ phono (100 ohm output)  pre and an Oppo player.
When it comes to line-level analog interconnections between source components and preamps issues relating to impedance compatibility are no different than when it comes to analog interconnections between preamps and power amps.

To assure impedance compatibility, in both cases the input impedance of the component receiving the signal should be at least 10 times as much as the output impedance of the component providing the signal, at the frequency within the audible range for which that output impedance is highest. In the case of many and probably most tube-based source components as well as many tube-based preamps output impedances are highest in the deep bass region, specifically at 20 Hz. And the output impedance at deep bass frequencies such as that can be much higher than the specified output impedance, which is usually based on a mid-range frequency such as 1 kHz.

Not meeting that criterion doesn’t necessarily mean that there will be a problem; it depends on how the impedances vary as a function of frequency. But meeting that criterion assures that there won’t be an impedance compatibility problem.

Many tube-based source components and tube-based preamps have specified output impedances that are reasonably low, but that can rise to thousands of ohms at 20 Hz. That kind of output impedance would result in significant rolloff and undesirable phase shifts in the deep bass region when driving 10K, regardless of whether the 10K is the input impedance of a preamp (driven by a tube-based source component) or the input impedance of a power amp (driven by a tube-based preamp).

Finally, as far as I can tell from the specs the input impedance of the Freya S is 10K regardless of whether it is used in active or passive mode.

Regards,
-- Al

Edit: I see you’ve added an indication of the source components you are using to your post just above. I would not expect those particular components to have a problem driving 10K.
Yeah if you can stretch a little to $800 this looks like a good candidate. I just recently was introduced to Mapletree Audio so I’m considering one myself...

http://www.mapletreeaudio.com/#Preamplifiers
I got one of these and like it alot: http://tubes4hifi.com/SP10.htm
Hits your price point, does a nice job...supposedly the circuit is modeled on the C-J preamps of yore.  This can be ordered from China on Ali-Express too, but Ray provides a warranty and US based support.

BTW, I got mine without the remote option...didn't love the way the remote worked.  The thing is dead quiet and uses 4 Chinese 12AX7s that I have tried to replace with "better" tubes, but the ones supplied consistently outperform any other I've tried...so I am just enjoying it as it is.