View Full Version : Tried a Crown IC150 Today.


JHoman
12-28-2009, 06:15 PM
I bought several old pieces at an estate sell a month or so ago. One item was a Crown IC 150 pre-amp. Looked great, full Walnut cabinet. Opened it up today and cleaned pots. Everything looked great.

I brought it into my listening room and hooked it to one of my AD B200 amps that drive my Cornwall Ones. Sound was quite boomy, then I noticed the loudness button was on. I cut off the loudness, went back to closer to what I am used to.

Played several different selections through it. Noticed it seemed to color the music a little to the high / mid sides. Mids were very tinny sounding and it seemed to loose some of the base definition.

Turned the loudness back on. Base was then booming and not defined. Cut it back off and tried to get a sound that I liked using the tone controls. Never found the sweet spot I was looking for.

Took it back out of the system and hooked my Caver C-11 back up and noticed a huge difference in a great way. Maybe my amps and my cornwalls and my room just favor the carver.

I may keep the Crown to try in another set up, who knows, I wish it sounded as good as it looks.:scratch2:

AFP1
12-28-2009, 06:37 PM
I owned a crown IC150/DC150 and it was some of the most sturdy and coolest looking equipment I have ever owned. I wanted to like it so bad that I tried it with every speaker I owned, east coast and west coast, horns and domes, cones and planars. It was the worst sounding equipment I ever owned. I thought about modding it but gave up on the project when I realized that in stock form it sounded worse than a fisher rack system I pulled off the side of the road and gave to a neighbor kid. I sold it on craigslist and have never regretted it. Just my opinion, others opinions will vary I'm sure, but what you are hearing is exactly how they sound. Andrew.

bobrown14
12-29-2009, 07:33 AM
From my research on Crown pre-amps, I've found the IC150 is not one of Crown's best achievements. The next one up the chain I think is the PSL-2 and then SL-1 then the venerable SL-2, from the Straight Line series. SL-2 being the one to get if you can afford one.

You would probably need to refresh components in the IC150 to get something better sound wise. You could try tuning it up to spec and see if that helps. Service manual and schems are on the Crown website along with service instructions.

Check this link out for the manuals and info..

http://www.crownaudio.com/gen_htm/legacy/legaclin.htm

Cheers,

Bob

dr*audio
12-29-2009, 07:41 AM
The opamps that were used in the IC150 are responsible for the crappy sound you hear. You can upgrade the opamps and the sound will be completely open and uncolored. I used LM833N opamps when I did this upgrade for a friend. There are other good ones you can try, such as the OP2228. After the upgrade, I put the IC150 into the tape monitor loop of my system and matched the gain so the level was the same in both positions of the tape monitor switch. Switching the monitor switch in and out sent the signal through the IC150 or bypassed it. There was no change to the sound when the IC150 was switched in. I had done this test before the upgrade and when the IC150 was switched in the sound degradation was immediately apparent.

70salesguy
12-29-2009, 08:09 AM
The SL-2 and the PSL-2 are effectively the same preamp.

The SL-2 (Straight Line Two) was available in Silver or Black. The last model that Crown made was only available in Black, and was designated as the PSL-2.

The most noticeable difference, other than only being available in Black, is that one of the inputs is designated as "CD".

The same designation applies with the FM-3 and the PFM-3.

There is, however, a significant difference between the FM-2 and FM-3 (or PFM-3). The FM-2 is a FM only tuner, whereas the FM-3 (and PFM-3) is an AM and FM tuner.

Consistently, PSL-2 units and PFM-3 units bring the highest prices. However, if you want a Silver finish on the units, you will have to find a SL-2.


http://www.crownaudio.com/pdf/legacy/psl2.pdf


The IC-150 was replaced by the IC-150A. Although I am not familiar with the particulars, there were differences between the two of them.

JHoman
12-29-2009, 10:11 AM
The opamps that were used in the IC150 are responsible for the crappy sound you hear. You can upgrade the opamps and the sound will be completely open and uncolored. I used LM833N opamps when I did this upgrade for a friend. There are other good ones you can try, such as the OP2228. After the upgrade, I put the IC150 into the tape monitor loop of my system and matched the gain so the level was the same in both positions of the tape monitor switch. Switching the monitor switch in and out sent the signal through the IC150 or bypassed it. There was no change to the sound when the IC150 was switched in. I had done this test before the upgrade and when the IC150 was switched in the sound degradation was immediately apparent.

All things considered, is replacing the OPamps all I need to do? I am far from a tech, but I am ok with a soldering iron. Is it simply un-solder, replace, re-solder, or do I need to send it to a tech to have this done? If so, is it really worth it?

thanks

Jeff

dr*audio
12-29-2009, 12:16 PM
Yes, all that is needed is replace the opamps. Some are in sockets and you can just plug in a new one. Others must be desoldered and a new on soldered in. I recommend installing sockets for those. Yes, it's worth doing. It makes the preamp sound like a wire with gain.

von.ah
12-29-2009, 03:48 PM
That is an interesting development... Thanks for the revelation, dr*audio! A lot of people are off now to find the unwanted IC150s... :D

dshoaf
12-29-2009, 05:59 PM
I had one back in the 70s along with the D150 power amp, and an SX-724 tape deck. Wonderful setup, actually, but the thing I hated the most was the ganged, dual volume control that had not friction setup. You had to 'grab' both gangs to keep them tracking together.

I also remember Crown issuing service bulletins on the replacement of tantalum caps due to DC voltage leakage. Any restoration would be a good time to confirm that yours has had such work done.

Cheers,

David

Brian
12-29-2009, 07:58 PM
One of the 3 worst preamps I ever experienced, even when new. For years I've espoused gutting them and using the hardware to build a good preamp in. Crown used some really fine hardware including the case, controls, switches, transformer, jackset, etc. Doc's suggestion is far less radical. As his suggestion is a direct substitution of the opamps, maybe the Crown can be salvagable and possibly be to the SS crowd what a Dyna PAS3x is to the tubeies.

Robie
12-29-2009, 09:01 PM
My college roommate for a year and a half had one and to my ears it was always too hard and brittle sounding. We had it paired to a Crown D-150 and DC-300A. While it was remarkably "crisp" sounding, it was very hard to listen to over lengthy periods. No offense to intended to anyone who has one or likes that kind of ultra clear/clean presentation.

Funny, after listening to that IC-150 for a while, I think I almost expected that type of sound from a preamp. Then when I bought my own McIntosh C-28 preamp and we substituted it for the Crown, we all thought the C-28 sounded a bit muddy.

dr*audio
12-29-2009, 09:12 PM
Now that I am home I checked my notes. I also just realized this was an SL-2 that I worked on, not a IC150. But I am sure the opamps and tantalum caps in the IC150 are responsible for the crappy sound, just as they were in the SL-2. Besides the opamps, I changed C121, C221, C233, C133 from 4.7uF tantalum caps to 4.7uF electrolytic caps, and upgraded C11 and C9 in the power supply from 330uF caps to 2200uF caps, bypassed with .1uF polyester film, and C12 and C13 from 4.7uF to 100uF, bypassed with .1uF polyester film.

cronie
01-19-2010, 05:56 PM
My college roommate for a year and a half had one and to my ears it was always too hard and brittle sounding. We had it paired to a Crown D-150 and DC-300A. While it was remarkably "crisp" sounding, it was very hard to listen to over lengthy periods. No offense to intended to anyone who has one or likes that kind of ultra clear/clean presentation.

Funny, after listening to that IC-150 for a while, I think I almost expected that type of sound from a preamp. Then when I bought my own McIntosh C-28 preamp and we substituted it for the Crown, we all thought the C-28 sounded a bit muddy.

Although I agree with every thing you say, a strange thing happens when you team the crown ic 150 + d150a or DC300a with Bose 901 series II All that brittleness and harshness is transformed into a beautiful transparency and clearness that seems to be so hard to find these days.That too crisp crown sound is mellowed by the bose tweeterless design to create a sound that is hard to beat in my opinion. The crown gear seems to fix what the bose lack. AS far as the ic150, the bass boost is way too much-corrected on the ic150a. Ive always dreamt of the day to have a system where I could turn the volume control up and hear straight thru to the music with no blanket over the speaker effect. This setup does this for me. almost every system sounds slightly muffled to me. Thoughts?

whoaru99
01-19-2010, 06:07 PM
Thoughts?

Yeah...if you like it, enjoy it. :thmbsp:

Robie
01-19-2010, 07:15 PM
Yeah...if you like it, enjoy it. :thmbsp:

Again, just my opinion and if you're happy with it, all the better. That's the thing; we all hear differently and have different tastes. I did have a D-150 for years (bought new in '75) and my friend still has it.

If the IC-150 has any electrolytics you may want to replace them given the age of the unit. The upgrades mentioned by dr*audio above sound interesting to me but if you're happy with it as it now is, just enjoy it. :thmbsp:

From what I've read, the Series 2 are the best of the 901s.

KentTeffeteller
01-19-2010, 08:56 PM
I own one which is at a transmitter site. I use it with a DC 300A power amp. Stock I didn't like it's sonics. I upgraded every op amp in it and recapped it. It now sounds excellent and very neutral. Try it! It's an easy preamp to tweak and the build quality is Crown Tough. Those switches and pots are top quality and deserve those improvements. Replace those tantalums and get out the soldering iron. You'll be rewarded many times over. :tresbon:

bharper
01-19-2010, 08:59 PM
I have a silver sl-2, and its performance is not what you would want to even hit a dog in the butt with.... very limited bandwidth and resolution. mine is relegated to being a gain device in the sub channel. perhaps dr audios suggestions would help, built well, nice pots and everything, but the performance absolutely stinks....

daveyh
01-22-2010, 09:14 PM
Now that I am home I checked my notes. I also just realized this was an SL-2 that I worked on, not a IC150. But I am sure the opamps and tantalum caps in the IC150 are responsible for the crappy sound, just as they were in the SL-2. Besides the opamps, I changed C121, C221, C233, C133 from 4.7uF tantalum caps to 4.7uF electrolytic caps, and upgraded C11 and C9 in the power supply from 330uF caps to 2200uF caps, bypassed with .1uF polyester film, and C12 and C13 from 4.7uF to 100uF, bypassed with .1uF polyester film.

I what to recap my IC150A and the service bulletin says to replace (4) MFD 4.7 20v tantalum caps on the phono board and (4) 1 MFD 30V tantalum on the logic board. And always replace C21, C22 and C24 which are also 4.7 MFD 20v.

My question is what would be a good replacement for these caps. Any electrolytic cap? Anyone have a source or part number I could look up??

Nakdoc
01-22-2010, 10:11 PM
Use non-polarized electrolytics, 4.7 uF 50Volt.
The IC 150 was much worse than the Dyna PAT-4. I can honestly say it is the worst preamp I've ever heard. I cannot imagine living with one even with a total upgrade, just because it looks like an IC150 forever.

daveyh
01-23-2010, 06:41 AM
Use non-polarized electrolytics, 4.7 uF 50Volt.
The IC 150 was much worse than the Dyna PAT-4. I can honestly say it is the worst preamp I've ever heard. I cannot imagine living with one even with a total upgrade, just because it looks like an IC150 forever.

Thanks for the reply. I am doing this as a favor for someone who gave me some other older audio equipment that was in the need of repair. So with that being said . . . are you saying to replace ALL the the caps I mentioned above with non-polarized electrolytics, 4.7 uF 50Volt? Even the 1 MFD's?

kimbosoups
04-08-2010, 12:06 AM
I used one for a couple of days, and it sound like a glass cutter. IMHO, they are just hopeless to make them sound good. Yes, they are make in the USA, but, don,t waste your time on them.

Brian
04-08-2010, 07:30 AM
When they were new they were about as bad sounding as you could get. If you are into rock only and love speakers like the JBL L-100 then maybe it will be okay for your tastes. I've always said the hardware is vert good and the unit is a candidate for gutting and building a good preamp into.

W9TR
04-08-2010, 07:42 AM
I owned one of these for years. The advice to upgrade the op amps and recap is solid. I think it had something horrible for op amps, a 709 varient or some such. Mechanically it is very well built. The stepped attenuator volume control is nice, though it gets noisy quickly. I like the panorama control that allows you to reduce the separation - great for headphones.