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Harmon Kardon 330B receiver...


mike stehr

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  • 11 months later...

Okay, so I've had the old 330B for (10?) years...I bought it for a friend at a yard sale with a pair of little Junk Advent speakers. He listened to the unit for a year, when it started to sound really nasty. I got the unit back, and traced the problem to a fried diode/resistor. I replaced those, and the caps on that board. It sounded fine again on my Cornwalls.

 

I've always like the "Nocturne" style of the 330B, along with the wood case. So I picked up a Pioneer receiver to give to my friend to cover the Harmon Kardon.

 

It does sound rather good on my Cornwalls, but it has the usual quirks that any 40 year old receiver would have...noisy pots, a nice tone, but recessed and weedy, with a bloat-ish bass.

Being a cap-coupled output amplifier, (with no relay) the receivers have a slight squirk-ish thump on power-up, and on power-down one can hear the music empty out of the capacitors with a squirk at the end.

I've watched Youtube videos of the HK 330B, they all do the same thing on power-up, and power-down.

 

Mine was getting really bad...On power-up, you get a nice loud SQUIR-WHOOMP!!, with a loud WHOOMP on power-down. The old Elnas were 40 years old...it was time.

 

I went ahead and dumped 30 bucks on all new electrolytic caps for the receiver. It's easy to work on and it has served me well over the years.

 

Picked up Nichicon audio grade caps, shooting for the best ones the Mouser had in stock for the values needed. The main reservoir Elna cap (2200uF 63v) is about twice the size of the Nichicon Gold Tune that replaced it. I found a piece of strip-board to mount the Nichicon 2200uF 63v cap to. It's a snap-in, so I bent the tabs a bit. I used hot glue to affix the cap to the top of the board.

The best way to do it is find a small diameter clamp for the Nichicon cap, and mount it to the strip-board...but this works...the cap is stuck on there well...

 

 post-4542-0-54900000-1418192076_thumb.jp post-4542-0-91500000-1418190687_thumb.jp

 

The rest of the little 40 year old Elna roaches were systematically eradicated...

 

post-4542-0-05140000-1418190866_thumb.jp

 

Upon cleaning atop the pre-main driver board, I bumped one of those dirty little two-pronged variable resistors...and it disintegrates! Fortunately, I had a couple 100K trimpots laying about. Made sure to be REAL careful around the 3K VR's, because I don't have those...

 

I found schematics online for HK 330A, and 330B. (model B2) Mine is a B1 so the schematic numbers don't match, slight circuit differences, etc...I plugged through it I suppose.

 

Still need to clean and lube the pots, pick up a couple of the weird fuse lamps (8v at 0.30A) and put it back together.

 

I can say it does sound better than it did...not by leaps and bounds, but it does sound better. It makes these little pair of junk Advent test speakers sing.

 

post-4542-0-99780000-1418191971_thumb.jp post-4542-0-07500000-1418192226_thumb.jp post-4542-0-71340000-1418192334_thumb.jp post-4542-0-89820000-1418192394_thumb.jp

Edited by mike stehr
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Happen to have a parts list that you needed for this? 

 

I can show the parts list that I have from my Mouser invoice, but I dunno if that will help much.

 

There is more than one version of the HK 330B receiver...some were made in Japan, some were made in Taiwan. Mine is the Taiwan made series B1. I don't know if your unit will show it, but on the back bottom right hand corner there may/should be the series of B model indication.

 

There is a PDF service manual online for 330A and B models with the Addendum. I went and tried to use this service manual to come up with a parts list, but found out real fast that the schematic part # indications didn't match with my model of 330B receiver. Along with some slight circuit differences, and capacitor values.

 

So I went the old fashioned approach, and looked through the circuit, determining cap values, voltages, and amount needed. With the unit I have, the PC boards have the schematic #s etc...

 

After all that trouble, I went and found the correct service manual on the Hi-Fi vinyl website.

One has to register on the site to access the PDF file however.

 

This is the service manual that matches my unit. HK 330B receiver, Technical manual Addendum. "This addendum to be used with all 330B models with a suffix "A" after the serial number."

This manual is the most informative with regard to the model number of my 330B receiver.

 

If you can determine what model number (series) of HK 330B receiver you have, then I could type up a part list pretty easy. There was 46 electrolytic capacitors to replace in my unit.

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  • 4 years later...

The first thing to do is to replace/upgrade the small rectifier diodes to a std. bridge. Any small bridge will do such as GBJL or KBJ1510.

The single main capacitor (AC-coupled) can be replaced with 15 or 18mF/63V that have the same size as original at low cost.

Do not use the same values as the original 2200uF/63V, this is especially so with the 1000uF/35V output capacitors that should be

replaced with 8700uF/35V at the same size as original. (AC-coupled amps where regarded as inferior as they could not muster the

20mF output capacitors that is required for full bandwith, 20-20kHz.) This is no longer the case. All this is important to observe

especially so if you are going to run the receiver at high volume (full output).

Edited by Howard_johnstone
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10 minutes ago, Howard_johnstone said:

The first thing to do is to replace/upgrade the small rectifier diodes to a std. bridge. Any small bridge will do such as GBJL or KBJ1510.

The single main capacitor (AC-coupled) can be replaced with 15 or 18mF/63V that have the same size as original at low cost.

Do not use the same values as the original 2200uF/63V, this is especially so with the 1000uF/35V output capacitors that should be

replaced with 8700uF/35V at the same size as original. (AC-coupled amps where regarded as inferior as they could not muster the

20mF output capacitors that is required for full bandwith, 20-20kHz.) This is no longer the case. All this is important to observe

especially so if you are going to run the receiver at high volume (full output).

This thread was last used 5 years ago.

 

Welcome to the forum, there are a lot of active threads that I'm sure your contributions would be appreciated.

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On 12/9/2014 at 10:22 PM, mike stehr said:

Okay, so I've had the old 330B for (10?) years...I bought it for a friend at a yard sale with a pair of little Junk Advent speakers. He listened to the unit for a year, when it started to sound really nasty. I got the unit back, and traced the problem to a fried diode/resistor. I replaced those, and the caps on that board. It sounded fine again on my Cornwalls.

 

I've always like the "Nocturne" style of the 330B, along with the wood case. So I picked up a Pioneer receiver to give to my friend to cover the Harmon Kardon.

 

It does sound rather good on my Cornwalls, but it has the usual quirks that any 40 year old receiver would have...noisy pots, a nice tone, but recessed and weedy, with a bloat-ish bass.

Being a cap-coupled output amplifier, (with no relay) the receivers have a slight squirk-ish thump on power-up, and on power-down one can hear the music empty out of the capacitors with a squirk at the end.

I've watched Youtube videos of the HK 330B, they all do the same thing on power-up, and power-down.

 

Mine was getting really bad...On power-up, you get a nice loud SQUIR-WHOOMP!!, with a loud WHOOMP on power-down. The old Elnas were 40 years old...it was time.

 

I went ahead and dumped 30 bucks on all new electrolytic caps for the receiver. It's easy to work on and it has served me well over the years.

 

Picked up Nichicon audio grade caps, shooting for the best ones the Mouser had in stock for the values needed. The main reservoir Elna cap (2200uF 63v) is about twice the size of the Nichicon Gold Tune that replaced it. I found a piece of strip-board to mount the Nichicon 2200uF 63v cap to. It's a snap-in, so I bent the tabs a bit. I used hot glue to affix the cap to the top of the board.

The best way to do it is find a small diameter clamp for the Nichicon cap, and mount it to the strip-board...but this works...the cap is stuck on there well...

 

 post-4542-0-54900000-1418192076_thumb.jp post-4542-0-91500000-1418190687_thumb.jp

 

The rest of the little 40 year old Elna roaches were systematically eradicated...

 

post-4542-0-05140000-1418190866_thumb.jp

 

Upon cleaning atop the pre-main driver board, I bumped one of those dirty little two-pronged variable resistors...and it disintegrates! Fortunately, I had a couple 100K trimpots laying about. Made sure to be REAL careful around the 3K VR's, because I don't have those...

 

I found schematics online for HK 330A, and 330B. (model B2) Mine is a B1 so the schematic numbers don't match, slight circuit differences, etc...I plugged through it I suppose.

 

Still need to clean and lube the pots, pick up a couple of the weird fuse lamps (8v at 0.30A) and put it back together.

 

I can say it does sound better than it did...not by leaps and bounds, but it does sound better. It makes these little pair of junk Advent test speakers sing.

 

post-4542-0-99780000-1418191971_thumb.jp post-4542-0-07500000-1418192226_thumb.jp post-4542-0-71340000-1418192334_thumb.jp post-4542-0-89820000-1418192394_thumb.jp

And what of the turn on noise? Has it gone?

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  • 1 year later...

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