Just bought a receiver, any suggestions for upgrading?

nspindel

I'm really psyched to have just purchased this on eBay:

http://www.ebay.com/itm/281595610770?_trksid=p2060778.m2749.l2649&ssPageName=STRK:MEBIDX:IT

The Harman Kardon HK 990 Vxi (not to be confused with HK's current model that uses the number 990) was the first piece of "real" hi-fi equipment that I ever bought myself, back in college in 1989. At the time, this receiver cost just under $2000, and was ranked in one of the magazines as one of the top 5 receivers ever made. I bought it just before I bought my CRS+'s, and the HK and the SDA's paired amazingly well. The amp has a high current mode, which the SDA's just loved.

Just before I joined this forum, the receiver started having a lot of static, especially when I changed the volume. It was 16 years old at that point, 2-channel audio seemed to be dead, and I was too stupid to realize that my receiver could probably be running again perfectly with one can of DeOxit! So I thought I had to either pay to get it repaired, or put what I thought would be a lot of money towards newer gear. I went with the throw it away option, and have regretted that mistake ever since I learned what a common problem this is and how easy it is to fix.

So I've been keeping an eye out for this model for a while over on the Bay, and have lost an auction or two in the past. I finally snatched one up at a good price, can't wait for it to arrive!

My wife and I are getting ready to put our house on the market next month, and things are still very up in the air in terms of where we're living next, and there's a large possibility that I'll be moving around a few times before we're settled in anywhere. Until the dust settles and my wife and I figure out the future, we may just be living in short-term apartments. My days of having a dedicated 2-channel room with loads of gear are drawing to an end, and a lot of my stuff is going into storage. I want to assemble a much smaller setup that can be moved around a lot more easier than what I currently have. I'm thinking my old HK receiver would be perfectly suited! Power amp, pre-amp, phono stage, and headphone amp all in one box. Add my turntable and Squeezebox, and I'm in business. That plus a few crates of records and a hard drive full of hi-rez audio files will definitely keep me happy, while me big rig sits boxed up in a climate controlled storage unit.

However...................

Having learned what I have over the years here, without even receiving the HK from the seller yet, I'm already thinking about upgrades. Particularly the caps, obviously. The piece is about 25 years old at this point, certainly I need to have a look at new caps. But there's likely to be hundreds of caps on a very tight circuit board, not nearly as conducive to DIY as a Polk crossover. I'm wondering how an amp overhaul works? Do all old caps need to be replaced? Or can only select important ones be replaced? What are the right types of caps to use in an amp? I've always used Sonicaps when doing crossovers, but how about in this application?

Any help/advice is appreciated!!!

tonyb

Not an expert, but it is a 2 channel receiver and shouldn't have hundreds of caps, resistors maybe, but not caps. I would replace them all, whats the point of replacing a few only to have one go south 2 months down the road ? Plus it would be more cost effective to do it once and done, have everything brought up to spec, clean and dusted and scrubbed behind the ears. After that's done, she may out last you.

nspindel

I can tell you that I saw the repair manual for a lower powered model in this line, and there are tons of caps.

ambiophonics

I would replace the power supply filter caps and probably the rest of the electrolytic caps as they do fail with age.

Here's the cap list from the service manual - electrolytics are indicated. I would suggest opening the amp up to figure out size and orientation. The manual is free over at hifiengine.

tonyb

Wow, that sure is a lot of caps....I stand corrected. Agreed though, power supply caps and electrolytic's should be priority.

nspindel

Thanks for the advice. I'll probably need some help identifying what's what!

Ambiophonics, you have a service manual for a 990 Vxi?

ambiophonics

nspindel wrote: »

Thanks for the advice. I'll probably need some help identifying what's what!

Ambiophonics, you have a service manual for a 990 Vxi?

http://www.hifiengine.com/manual_library/harman-kardon/hk990vxi.shtml

You may need to sign up for a free account to download the manuals. The site is a great resource.

nspindel

Awesome, I was looking on that site, but I didn't see it because they have it listed as an Audio Video Receiver.

If you notice in the service manual, the caps you listed are only the ones on the main circuit board. There are additional caps on the tone control pc board, the equalizer pc board, the control pc board, the led pc board, the function pc board, the av pc board, the tuner, etc.

ambiophonics

I didn't realize that, I just scrolled down to the parts list that included the filter caps. It'll be a good deal of work to replace every electrolytic cap in that receiver, maybe start with the filter caps and go from there?

nspindel

Not sure. That's what I'm asking

nspindel

I'll probably just bring it into a repair shop near me and get it overhauled. The more I'm thinking about this, the more I'm losing my nerve.

nspindel

Also, looks like I exaggerated the price it used to sell for. It retailed for around $1100 according to what I'm reading.

nspindel

Arrived today, in excellent shape. Better than my old one, and the eBay seller was a stereo repair shop, the guy had already cleaned all the contacts. He didn't replace the caps, so I might still think about those...

Sounds great as well. Not nearly my Krell, but I wouldn't expect it to be. Excited to be reunited with the amp I had when I was 20!

voltz

sounds great Neil, what are you pairing it with? I'm glad you enjoying it.

nspindel

With my 4.1TL's. Same stereo I had at 25 years ago!