Analog Domain EQs

Anyone have any recommendations regarding equalizers that fully operate in the analog domain? I'm looking to do some room correction, but I don't want a digital component in my tubed-component chain. Ideally, the unit would have single ended inputs (as my system doesn't have XLR connections and I would prefer not to use RCA-XLR converters).
Audio Control makes good stuff at reasonable cost. In particular, their "Richter Scale" equalizer/analyser covers the range below 150 Hz, (which is probably where you need it) and includes a crossover should you wish to biamp, or subwoof.
the Rives PARC is the best I have heard in the analog domain. however, it's limited just by that fact (not digital.) For room correction with EQ and crossover thrown in, for about the same $, check out the DEQX. Yes, it's digital, but doesn't sound like it. Do you have a CD player? Then you already have digital going on so don't worry about the 'tubed-component chain'. the DEQX can take digital in and offers digital out if desired.

I can't figure out what type of upsampling/oversampling the DEQX performs....Ed, do you know?
hi Lefty-

I forget offhand -it's on their site I think. I know it can take digital in in various rates, and I believe it does A->D (for analog source inputs) @ at least 24/96, maybe higher. It's software upgradable so pretty future proof (as much as any digital piece can be.).

will let you know how it works out when mine comes in (soon).

Looking forward to your comments, Ed. I couldnt find any information on the DAC/ADC, except that its 24 bit - no word on upsampling. Where did you purchase yours?
ah, the DEQX is 24/196. Interesting...looking forward to your comments on the device. Are you connecting between your preamp and amp, or between your source(s) and preamp?
Will be between source and amps - it has the option of a built-in volume control/preamp, which I'll be getting with mine. So, ultimately it functions as 3 or 4 separate pieces in one: preamp, crossover, speaker EQ, room EQ, ( and upsampler) and can also convert single ended to differential balanced (in or out) if need be.

will post more when it arrives and I have time to configure it.

I asked this earlier--is it okay to use an equalizer designed for professional use (studio, live performance) in a home audio system? I got one affirmative answer in my earlier thread.

As for digital EQs, I'm concerned about what they will do to my SACDs since the sampling rates on these machines are considerably lower (on the models I've seen) than SACD sampling rates.


Your analysis is the same as mine: I don't want a digital EQ in my signal chain if there is hi-res source material playing. That leaves analog EQs as the only choices. Not many options, outside of Rives' solution and studio EQs. I'd be sure that you can define the frequencies, the Q, and the amount of attenuation (or gain) that you want to provide. Many of the studio EQs have few predefined freq bands, and limited ability to control Q outside of "narrow" and "wide" settings". If you find something of interest, please post - i'm quite interested.
You will not be able to find high quality non-XLR pro EQs. If you have flexibility on that requirement, then you should consider the Manley Massive Passive, the Millennia NSEQ-2 or the GML models. These are all very high quality units and can be quite useful for some purposes, but they cannot do what the sophisticated programmable digital EQs can do to alleviate room problems.
" I don't want a digital EQ in my signal chain if there is hi-res source material playing. "

IMNSHO, Get over it. It's a farce to think that you can hear the difference resampling would make. Don't obsess over minutae like this (typical audiophilia...we are all guilty at times of it)... just listen and then judge. Blind if possible. Who's to say the analog domain EQ's sound better? They undoubtedly have colorations of their own.

As an FYI, Pro EQ's are designed usually for different signal levels than consumer gear, I believe.

Leftitself: gain is usually not recommended. most EQ users live by the credo 'cut only'. Don't try to fill in dips...

Digital Parametric with Q to 1/10 octave or better is the only way to go, IMHO. Treat the room as best you can first.