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What do you think about a CJ PV9A with a Mcintosh MC225

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DenverJW

New Member
Hi Everyone, I was wondering if anyone can help me determine if a Conrad Johnson PV9A preamp would be a good match for my Mcintosh MC225? I am new at all this and could use some help. I am worried about matching the components and don't have enough knowledge or experience to make the decision alone. The one thing I keep reading is that there may be a gain issue?? I want to make sure that I have good control of the volume range with sensitive and non-sensitive speakers. I want the flexibility to try many different types, from Magnepans to Harbeth, Klipsch, ZU, and others. Please help I need to pull the trigger soon. Here are the specs of the CJ:

Gain: Phono stage 47dB High level 31dB Output: Maximum 20V Rated at 2.5V Phase:
Line stage inverts phase of all inputs.
Phono overload: in excess of 200 mv at 1KHz Response: bandpass 2Hz to more than 100 KHz RIAA equalization to +/- .25dB (20Hz-20KHz) Hum and noise(20Hz-20KHz): phono inputs: 77dB below 10mv input Line level: 86dB below 2.5V output Distortion: THD less than .25% IM less than .25% Ouput impedance: less than 200 ohms
 
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I will be using a Turntable and a DAC from a Mac Mini running Roon and tidal mostly. CDs occasionally. I read that the gain may be too much for a digital source?
 
Congrats on cool system. I can speak to CJ PV 7 with Mc solid states - MC2100, 2205 and 2255. There seems to be somewhat of consensus for tubes on input and SS on output. Some of those speakers seem would need more output Best to match the amp with speakers.

In my system the CJ added warmth, depth and large soundstage. I used Sony ES 9000 for CD, Sonos Connect then Bluesound Node 2 for digital through Music Fidelity DAC. No issue for me on gain.

You can try different tubes of course. I had RCAs, Mullards and Telefunken. My preference was the TF's for slightly more detail. Best advice is to try it out and see what you prefer.
 
don't forget, CJ pre's of that type invert phase in the chain. You will need to reverse positive/negative connections to your speakers.
 
Thank you, I'm excited to put it together. Just trying to decide if this is a good pre to try? I'm hoping to plug it in and have a decent match without too much noise or a volume pot that is too weak or sensitive. I also know it's important to match the Ohms with the 10X rule. But I did the math and it's way within spec, almost looks like too much.

200 output Ohms (from the Pre) X 10 = 2,000 and the Mcintosh MC225 says Input impedance: 250,000 ohms. What the heck? It's not even close, is this a potential match? Or a colossal mismatch?
 
My McIntosh MC-275 Commemorative Edition tube amp is currently awaiting (my) repair (blown electrolytics and resistors, when I get to it). So, I re-installed my two McIntosh MC-30's in that system which also uses a CJ PV-8 pre-amp. Sounds magical! Speakers are Spica TC-50's mounted on Sound Anchor stands. I would imagine your MC-225 should mate well with the PV-9
 
Not a CJ but I use a Audio Research SP8 into my MC40 monoblocks, sounds awesome.
If the preamp gives you to much gain they sell inline attenuators that plug into your RCA cables. I don't need them.

BillWojo
 
BillWojo said:
Not a CJ but I use a Audio Research SP8 into my MC40 monoblocks, sounds awesome.
If the preamp gives you to much gain they sell inline attenuators that plug into your RCA cables. I don't need them.

BillWojo
Click to expand...

The MC225 has built-in gain controls, so it can be adjusted if needed for best S/N.
 
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