Head-Fi.org › Forums › Equipment Forums › Dedicated Source Components › My New Project - McIntosh MC 2505 Solid State Power Amplifier
New Posts  All Forums:Forum Nav:

My New Project - McIntosh MC 2505 Solid State Power Amplifier

post #1 of 12
Thread Starter 

My dad had a pretty nice speaker set up with his record player that I used to enjoy (and dance to!) as a kid, but ever since about 15 years ago, it's been collecting dust.


I dusted off the amp and am trying to see if it will have any use in my new, computer-based, setup.  It's  vintage solid  state amp (McIntoch MC 2505) - I'm still a newbie when it comes to anything head/hi-fi so I've got to ask... Am I doing this right?!


My current setup is: Macbook Pro (ALAC through iTunes) --> uDAC (RCA outs, Red/White 1/4" Stereo output) --> into Stereo Input on the MC 2505.  


Basically, I wanted to use the uDAC as DAC only (S/PDIF) --> MC2505 does all the amping/volume control.

Unfortunately, I can't use the coaxial out on the uDAC as there's no coaxial into the MC2505 (For obvious reasons).  


So basically the uDAC is amping the USB signal from macbook..which is then getting amped again by the MC2505.  I've messed with the L/R gain settings some... but didn't need to raise it by much (they're driving the ATH-M50's... which are EASILY driven).


I've noticed that the sound is a bit warmer and "rounder", especially in the bottom end but nothing mind blowing.  Plugging straight into the uDAC's headphone out actually sounds clearer, but the treble is a bit more irritating; also, the it sounds a bit "flatter", if that makes any sense O_o


Any tips or criticisms?


my dad also has a Mc pre-amp, but I don't see the need for putting it into this setup, right?  Attached a picture for reference :]IMGP3640.JPG

post #2 of 12
Thread Starter 

I've got to add... maybe I'm doing something wrong, but this amp is really noisy!  I hear a lots of white noise during quiet parts of songs, during a classical guitar solo, etc.etc.  :/



post #3 of 12
Part of it could be that you're double-amping. Have you thought about getting a DAC without an amp?

Also, you might be getting a little noise off the 2505. It is a really nice piece of hardware, but the electrolytics in the power supply take a beating from the AC. You might want to think about replacing them.
post #4 of 12
Thread Starter 

thanks for your input :]  I was getting worried this would just end up floating down the threads without any responses :(


the uDAC can act as a standalone DAC with coaxial out (S/PDIF) but unfortunately the 2505 only has a RCA stereo input.  Would it works to get a coaxial splitter like this one? http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10236&cs_id=1023603&p_id=6261&seq=1&format=2


Or does that not work because it's a "digital" signal?  


As far are replacing the electrolytics... how much would that cost?  The whole reason for using vintage gear was the save money :] 

post #5 of 12

HEY!!!  I have my eye on those...my friend loves his and found a 2500 for me (no VU meters) but I need other things first.


So, you should hold onto that.


But, if you decide you don't want to...please let me know!


I have seen at least one "service" and website where they would refurbish all the parts that wear/age on those but it was definitely up there in the hundreds, run a Google search.


Again, that's a good one if you are going to go vintage...mmmmm.

post #6 of 12
Thread Starter 

haha I can sense your excitement jumping out from your post :P  I've been listening through it on & off all day and I'm appreciating the really "warm & full" sound I've been getting through it.  I A/B'ed it with the uDAC's headphone out and the uDAC, though great, definitely sounds colder and even a bit shrill in the highs (weird huh?).  


My dad will probably want to "keep it in the family", but who knows :]  It's so funny - I have to use low gain for L/R (Both set at around the 8:30 mark, with 6 being "off") since my M50's are driven so easily.  The meter's bounce around -20 to -10 db with the meter range set to -20! hahaha


For those of you skipping to this post, I'd ask if you can read the question I posed in post#4 as I'm still lost on the matter :/ 

post #7 of 12

Sorry, my friend who has that amp is in Canada on a trip right now so I can't just ask him if that adapter will work to connect your u-DAC to the McIntosh.

post #8 of 12

Your not double amping, your misunderstanding , the udac has rca outputs which are lineouts not amped a fixed lineout is around 2vrms the udac's volume pot allows you to control this so you get 0 - 2vrms, your only double amping if your using the udacs headphone jack which has a amp built in. I would advise you use the udacs rca out and set the volume pot to max and also set the pc's volume to max and control the volume with the Mcintosh amp thats the best sound your gonna get out the udac, if you don't like it then consider getting different usb dac.

Edited by JRG1990 - 4/5/11 at 6:02am
post #9 of 12
Thread Starter 

Thanks JRG!  I'm glad you came along :]  I was just assumed I was double amping because the volume pot on the uDAC was changing the volume.  Your explanation makes sense as the volume changes via the uDAC were pretty minimal.


Head-Fi is awesome.  I've read on some other McIntosh forums to take advantage of a pre-amp too.  My dad has a McIntosh preamp of the same set as the 2505, but why would I need it if I'm not switching through or combining a bunch of audio inputs???  Does it do anything to the sound other than equalize volume levels of various inputs?

post #10 of 12

I think the pre-amp is so you can connect to multiple devices at once, tape , cd , vinyl , tuner etc , you don't need it unless you want to do this, it will probley do nothing more than pass the audio signal straight though, if you don't need it don't use it the less in the signal path the better.

post #11 of 12

Big blue meters, comfortable music on the warm side of neutral, whats not to like?  The uDac is the weak link in your system, put it up first on the upgrade list, when funds allow, keep the uDac for when you are not at home with your amp.


1) You don't need the pre-amp until you use more than one source.  You can control the volume on the amp itself.

2) One day, you should consider getting your amp "looked at" as the capacitors are probably old enough to need looking at/replacing.

3) Consider looking for some speakers man...


McIntosh is great Americana vintage gear.  Of course they are still in business, and still making great gear.  There are several businesses that specialize in maintaining/restoring these amps.  Look at the McIntosh section of AudioKarma for some more information about your amp.  At the bottom of that page are 2 vendors that do great McIntosh work.

post #12 of 12
Thread Starter 

Brubeck sounds phenomenal through the McIntosh! Well, he sounds great regardless, but the extra "fullness" is something in itself :]


What DAC do you recommend?  Mind you, I just got out of grad school and am currently job-less so I can't afford anything too crazy :/  I'm applying for professional schooling soon, so money will be tight for some time.

New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Dedicated Source Components
Head-Fi.org › Forums › Equipment Forums › Dedicated Source Components › My New Project - McIntosh MC 2505 Solid State Power Amplifier