McIntosh C70 arrived today

[Ger707]

Originally Posted by miatadan

My stuff arrived including the C70
Christmas early for me now

Congratulations! Looking forward to a review

[miatadan]

Originally Posted by Ger707

Congratulations! Looking forward to a review

I have been using the combo C70 + MC312 for a while now

Since I am using Acoustat Spectra 22's now, I can have review as for 6 month's used same model of speakers with the C2300 + MC302.

With the C70 volume levels are higher as there is no input trim adjustment (
C2300 had input gain @ + 3db for input of dac I was using ) I do like that the tone controls are at 20Hz and 20,000Hz and leave bass @ +2db since I am running full range electrostatics. Really like having actually knobs for control's compared to most stuff being menu settings on the C2300.

So far for me volume level is set at high way mark, or if playing music louder 2 leds more. Acoustats are 83 db at 1 watt, 1 meter.

Compared to C2300 + MC302, sound is smoother and more dynamics. Meter's on MC312 show average of 3 watt's to 30 watt's.

A lot more headroom now, if I do what I consider torture test playing Phil Collin's " I Don't Care Anymore " at 110db volume levels - meters show between 300 watts & 600 watts with power guard flashing. The MC302 would just shut down altogether and than have too wait 10 minutes to re-power amplifier. Even at extreme volumes heatsinks just gets warm not hot compared to the MC302. Higher headroom rating and double filter caps definitely improved the performance.

Long term goal is to switch the Acoustat Spectra 22's for Martin Logan CLX Art or Quad ESL 2812.

Dan

[cmusic]

Hi everyone
I purchased a C70 this morning from JWJW and have a question about integrating it with a Denon AVR. I know the C70 doesn’t have HT bypass but was wondering how to achieve unity gain.
Thank you in advance for your time.

[W9TR]

Do you have a power amplifier with meters or a sound pressure level meter?

[cmusic]

I have a MC 452 and an dB app in my iPhone.

[W9TR]

Perfect!

Find a line level source you can plug directly into your 452. Something like a DAC or CD player.

Find a 1 kHz sine test tone you can play through your source. Most music services have at least one test disc you can play.

Disconnect your speakers from the amp.

Play the test tone and record the meter reading on the amp.

Connect your C70 to the amp, your DAC or CD player to your C70 and adjust the C70 volume until you get the same reading as you obtained with the source connected directly to the amp.

Done! You have set the C70 to unity gain.

You will not harm your 452 by disconnecting the speakers.

Then you can run the room optimization program in your pre/pro. You don’t have to be exact here as the room optimization program will accommodate any minor differences in gain.

I think the C70 uses LED’s to indicate volume so you’ll need to find the closest spot where an LED just turns on and use that so that you can reliably repeat the correct volume setting.

Make sense?

Tom

[Levitator]

Great advice Tom!

[damacman]

The problem is ... And it's a fairly good one ... Is forgetting to reduce the volume setting on the preamp when using it with a standard two ch source. I did that with a C100 for a short while and unity was something like 70 or 80 on the volume setting. After a few oopses, I replaced it with a C200, which has HT PassThru.

So just use extra caution.

[cmusic]

Great
That is great advice!!
I will run through the steps soon now that I have my Lumin streamer connected directly to the MC452.
I listen to music 4-5 days out the week but only 1 movie a week if that so I gave up on the HT bypass requirement.

Thank you again for sharing the knowledge.
Carlos

[W9TR]

On my C 2300 unity gain is 70 on the front panel display. So good point - be careful!