Pioneer Spec-2 - Unstable Bias

Just got he HE129-NDs today, EW are these the same layout as the US relays you used int he pic? And if so does it matter which direction it is mounted . I dont see any markings on these i got today .
 
The two inner pins should be the coil, and the outer pins are the contacts. You can confirm this with an ohmmeter. Measuring between the two inner pins should read about 2Kohms, and between the two outer pins should be an open circuit.
 
Big bump but I just wanted to update part numbers for the relay. It seems the HE3351A2400 relay is being phased out, Mouser no longer carries them and Digikey only has 79 left. Thankfully there is a newer replacement with plenty of stock at both places, part numbers are 934-HE3621A2400 for Mouser and HE210-ND for Digikey. Only differences are the coil is 2150 ohms instead of 2K (non-issue) and it's physically smaller by 5 mm in length and 2 mm thinner, but it has the same height and the same pin-out.
 
I know this thread is 5 years old but EchoWars helped me through the year's with several projects. I know he's been gone from this site for several year's but the information he shared lives on.

 
There's a lot of possible causes, but I'm speaking about 'no' measurable bias current, or current that fluctuates from a normal value to something lower, and back again (or not).

The root of the problem is Pioneer's protection design, which is effective but horribly complex. The Spec-2 contains no less than eight (8!) relays, performing various functions ranging from a soft-start, to switching in an alternate set of resistors to change the current limiting curve when the amp is switched from 8 ohm to 4 ohm operation.

The relay I am speaking about at the moment interrupts the flow through the current mirror in the bias section of the main amp. The protection circuit of the amp does not allow bias current to flow until the last moment of operation. I'm not particularly crazy about the design, but it is what it is, and if you bypass the relay, you'll get nasty thumps as the protection circuit relinquishes control on power up.

What I have been finding with increasing frequency is that, once the protection has finished its power-up sequence, bias is unsteady, low, or non-existent. This will result in various levels of distortion in the affected channel - ranging from gritty highs and unbelievably flabby bass (think 'nearly unlistenable') to near total loss of signal.

The culprit is RL1 (as designated on the individual amp schematic and the foil pattern), or RL5 'a' and 'b', as designated on the large fold-out schematic. There is one on each driver board, and you can quickly see on the schematic that this relay is designed to interrupt the bias current. The stock Pioneer relay is, frankly, crap, and is likely the cause of a lot of crappy sounding Spec 2 amps.

Here is what the part looks like (circled in yellow):
So what is the most up-to-date replacement available for this relay, mouser PN# is you can. thanks. And installing pinout?
I am talking about RL1. can someone help with the right replacement and a markup of installing it as the pinout is going to be different for the replacement. and should RL2 be replaced also or is that ok?

D9 is this a good replacement? Mouser #: 934-HE3351A2400 and if so, is the installation like the picture of the other part in the beginning of this post.
 

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So what is the most up-to-date replacement available for this relay, mouser PN# is you can. thanks. And installing pinout?
I am talking about RL1. can someone help with the right replacement and a markup of installing it as the pinout is going to be different for the replacement. and should RL2 be replaced also or is that ok?

D9 is this a good replacement? Mouser #: 934-HE3351A2400 and if so, is the installation like the picture of the other part in the beginning of this post.
Sadly, Glenn (EchoWars) has been MIA for about six and a half years now.
 
Is that your pic that you posted? Does/did it work? It's a SPST relay. Two NO contacts, two pins for the coil. Not much to do wrong there.
 
Is that your pic that you posted? Does/did it work? It's a SPST relay. Two NO contacts, two pins for the coil. Not much to do wrong there.
No that's not my picture. That's a picture from earlier at the beginning of this post with a different part. I'm asking what is the new part number? And is the part I attached a link to the right one well that one work? And if so is that the same pin out as in the picture from earlier in the post many years ago with the other part?

And I don't even know if that's the issue. it's just what i'm going to try first period i just need to know what the right part to get RL1 is and the new wiring for that part.
 
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You are going to have to look at the datasheets and make the determination. Every part (relay or what have you) has a datasheet.
 
You are going to have to look at the datasheets and make the determination. Every part (relay or what have you) has a datasheet.
So all the pioneer help guys are gone now? I'm on the form because I need help.

And I don't even know if that's the problem with the left channel. So I don't want to compound my issue with putting it in the wrong part.
 
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I just found two of these "US Relays part #SD1A24D" on eBay and went ahead and ordered them. I was just wondering if somebody could have crossed referenced something up to date but that's OK.
 
I just found two of these "US Relays part #SD1A24D" on eBay and went ahead and ordered them. I was just wondering if somebody could have crossed referenced something up to date but that's OK.
The part referenced by Matt above still exists. Why didn’t you buy that one?
Random parts on eBay is never a good idea.

I’ve used it many times. Pinout is in the service manual, and you have the picture showing the correct installation.

 
Thank you for the new link I just bought two of those. So I have two of the other ones he recommended coming also that's fine. But I will use the ones from digikey as that's the ones he shows in the picture of how he installed them. So I'll have that right installation.
Thank you for the link. And FYI I didn't buy random parts on eBay I bought the other ones he referenced that were the same part just a different manufacturer.

I'm just not a fan of digikey. They charge $7.00 to ship those two parts that should cost $1.50. I usually don't do business with companies that take advantage of people like that Mauser shipping rates are way better.
 
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Last time I checked, postage isn't free. Packing materials and boxes/envelopes aren't free. The labor to pay some one to pull a part, pack it, someone else to QC it, and put it in a box and send it isn't free. Probably won't come in at a buck and a half anywhere outside of the third world.
 
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