Karl vd Berg
Super Member
Thank you, Anti_Skate!
Just notice that the left channel in the unit here was fuzzy, too
Just notice that the left channel in the unit here was fuzzy, too
Sound Impressions of Restoration/Upgrade
Before I started the Kenwood C1 restoration/upgrade, I listened for a couple of days to it paired to the M1 or a restored harman/kardon hk770 or a Marantz 170DC. The listening sessions used CD and LP recordings that I'm very familiar with (some examples): Steely Dan/Aja; Miles Davis/Kind of Blue; Dire Straits/Love Over Gold; Beatles/Abbey Road; Fournier/Bach Solo Cello Suites; Duke Ellington Orchestra/Digital Duke; Karajan, 1962 Beethoven Symphony cycle. I even took a few notes of these initial listening impressions since I didn't want to rely on just my sonic memory since it would be a couple of months before I could get to the C1 restoration (a Marantz 2235B was currently on the bench). The C1 as received was only fair sounding; with the phono stage noticeably poorer than the line stage. The bass was overly full(bloated), mid-range and treble range were recessed, further back in the sound-stage, the treble had a brash, overly sibilant quality.
The restoration/upgrade of the C1 significantly improved the sound of the preamplifier. It now sounds quite similar to a restored Hafler DH-110 now: overall, very clear and neutral, with a deep and "tight" sounding bass range. The treble range is very natural sounding with lots of detail (e.g., the different cymbal sounds are easily discerned) and the reproduction of the middle frequencies/vocals is now very realistic; singers sound "live" in the living room (the little vocal "ticks" and 'hiccups" are easily heard, and "mumbled" lyrics are easier to be understood, e.g., Morrison in L.A. Woman. Previously, Unican Eric used a tube preamp (http://www.audiokarma.org/forums/showthread.php?t=580444) with the M1 since it was so much better than the stock C1, he has since told me that is no longer the case: the restored/upgraded C1 is more than capable of excellent sound.
Restored/upgraded Kenwood set sitting pretty
Old parts removed from C1
Leestereo I would trust if I did not do the work myself. I do not know if he takes these in but best I recall he does. Send him a PM and see. Welcome to AK haukie !Hi i am new here , i live in milwaukee wi.(franklin) and would like to know if you could recommend someone i could trust to upgrade my kenwood c1-Thanks
Hi,Yes, no ceramics in my amps is
Richard
Thank you, rjsalviThe short answer is, yes, since this is an audio forum. There are a couple/few "classes" of ceramic caps and NP0/C0G are the most stable (materials used in their construction afford this). They make great op-amp bypass caps!
That link to the Japanese restorer amp8 is awesome. I could look at that for hours ! Thanks for that. Bookmarked...Thank you, rjsalvi Is that a Pioneer SPEC board ?
I saw Leestereo replacing a few ceramic caps for NP0/C0G ones at first page - here - and I thought that it could be done for every ceramic cap. But saw other restorations (Japanese amp8 restorer does it often) where those green Mylar caps were also replaced by other type of film capacitor, like in the pic below (sorry for that).
I had to do the same with the previous Nippon Chemicon's KMF at PSU, turning the volume up high and there was no bass and weak sound. Now it's different, the sound is much more present, full, nicer. I think that may be room for further improvement, with C0G multi layer ceramic caps, soft recovery rectifiers and a couple of fresh Panasonic FC caps in the PSU...... Still does not sound right, still have to turn the volume control up to high. It was this way before the restore as well.. Hold that thought.
Are you speaking of ceramics ?? (" Caps feeding the opamps (C45, C46) are now fresh Nichicon's PW").
My numbers are different because it is a C2 not a C1. I have some stacked caps...Just FYI.