I talked to a tech up north who used to work for Soundstream. He said the same thing. I'm replacing the FED with a higher rating that the tech recommended and also upgrading the output transistors as they're a combo of two different types. I guess mine was build as they were transitioning to new parts. Hopefully this will fix it. Since its so old I also replaced the caps.
What were the replacement parts he recommended?
I don't know of any rectifiers that can handle more than 16 amps in the to-220 package.
I've seen the TIP142T and TIP147T in some of the amps. They have a slightly (depending on the datasheet you reference) higher current rating.
If that's what he recommended, make sure that you get the ones in the TO-220 case. The TIP142, TIP147, TIP142TU and the TIP147TU are in a TO-3P case.
I don't know of any rectifiers that can handle more than 16 amps in the to-220 package.
I've seen the TIP142T and TIP147T in some of the amps. They have a slightly (depending on the datasheet you reference) higher current rating.
If that's what he recommended, make sure that you get the ones in the TO-220 case. The TIP142, TIP147, TIP142TU and the TIP147TU are in a TO-3P case.
The MC-245 uses TIP142 and 147 in the TO-218 case. They can be replaced with the later case style TO-220 T versions. Same device, smaller footprint package, used in Rubicon series amps A couple years back.
I know of NO replacement for the FED diode because of its "special polarity consideration", and its rather difficult to find BUT there is a fella on E-bay by the name of Jaime that sells SoundStream parts (all original) He worked for SoundStream for 10 years. Look for JandRelectronics on E-bay. The FED16BT is special the diodes do not form either common cathode or anode configuration like all the other standard packages do. Check the diode directions on it case package < its special > LINKY: http://cgi.ebay.com/ws/eBayISAPI.dl...Sell_LogicX&refwidgettype=cross_promot_widget
He also can repair the unit to original specs, along with sell you all the correct parts to complete the job yourself. He might even be able to dig up a print somewhere, since Soundstream seems to have lost them over the years.
He is a one stop shop for ALL Vintage SoundStream parts
Hope this help, and good luck
I know of NO replacement for the FED diode because of its "special polarity consideration", and its rather difficult to find BUT there is a fella on E-bay by the name of Jaime that sells SoundStream parts (all original) He worked for SoundStream for 10 years. Look for JandRelectronics on E-bay. The FED16BT is special the diodes do not form either common cathode or anode configuration like all the other standard packages do. Check the diode directions on it case package < its special > LINKY: http://cgi.ebay.com/ws/eBayISAPI.dl...Sell_LogicX&refwidgettype=cross_promot_widget
He also can repair the unit to original specs, along with sell you all the correct parts to complete the job yourself. He might even be able to dig up a print somewhere, since Soundstream seems to have lost them over the years.
He is a one stop shop for ALL Vintage SoundStream parts
Hope this help, and good luck
The FEP16BTD has the same configuration as the original soundstream parts. It has the same specs so it wouldn't be an upgrade.
I didn't know that SS ever used TO-218 parts. Coustic switched from the TIP142/147 to the MJH110xx series transistors. I think they used the MJH11017and MJH11018. They were a direct replacement for the coustic amps. I don't know if they could be used in the SS amps.
http://www.onsemi.com/pub/Collateral/MJH11017-D.PDF
J&R electronics is definitely a good place to get SS parts. I've recieved top-notch service every time I've ordered from him.
I didn't know that SS ever used TO-218 parts. Coustic switched from the TIP142/147 to the MJH110xx series transistors. I think they used the MJH11017and MJH11018. They were a direct replacement for the coustic amps. I don't know if they could be used in the SS amps.
http://www.onsemi.com/pub/Collateral/MJH11017-D.PDF
J&R electronics is definitely a good place to get SS parts. I've recieved top-notch service every time I've ordered from him.
Evening guy's, sorry had to work on a few computers. So I was away for a bit.
SoundStream used three different configuration dual diodes. The FEP, the FEN, and the FED.
The FEP is common cathode, the FEN is common anode, the FED is anode , cathode, cathode.
Yeah Jaime is the best You gotta love the guy. He is the fastest, and nicest supplier I ever had.
I agree you can use more modern outputs like you linked to, But TIP142's and 147's are plentiful everywhere. The T version is used only in the Rubicon series though it could be used in the MC series as well. Jaime has the T series, just not listed on E-bay.
I just repaired two MC-140's last week and TIP 142' and 147's were under the card, so I replaced them with the same.
hope this helps
my pic of the FED dual diode would not upload so sorry guys, I guess its too big
SoundStream used three different configuration dual diodes. The FEP, the FEN, and the FED.
The FEP is common cathode, the FEN is common anode, the FED is anode , cathode, cathode.
Yeah Jaime is the best
You gotta love the guy. He is the fastest, and nicest supplier I ever had.I agree you can use more modern outputs like you linked to, But TIP142's and 147's are plentiful everywhere. The T version is used only in the Rubicon series though it could be used in the MC series as well. Jaime has the T series, just not listed on E-bay.
I just repaired two MC-140's last week and TIP 142' and 147's were under the card, so I replaced them with the same.
hope this helps
my pic of the FED dual diode would not upload so sorry guys, I guess its too big
Thanks for all the great posts! Yup all the parts are coming from Jaime. I'm replacing all the output transistors going from 101 to 102 and 106 to 107. The amp had a couple 107s in it so it was mismatched. I'm the original owner so it came this way from the factory. Jaime said they switched to the 102/107 combo later.
I don't know the part # of the dual diodes. I'll upload that when I get them.
I did find a burned resistor in one of the channel's high pass filter network. It didn't destroy the resistor just changed its resistance by about 1 Ohm. Everything else look visually ok. The only strange thing is I cannot get continuity between common ground and the neg pad for the 2200uF cap that is closest to the sub speaker connections. Before with the blown diode there was continuity between the +/- of that caps pads.
As long as I'm deep into this board are there any mods that would improve the sound of this amp? I'd love to figure out how to put tube minatures in somewhere to get a nice tubey sound.
I don't know the part # of the dual diodes. I'll upload that when I get them.
I did find a burned resistor in one of the channel's high pass filter network. It didn't destroy the resistor just changed its resistance by about 1 Ohm. Everything else look visually ok. The only strange thing is I cannot get continuity between common ground and the neg pad for the 2200uF cap that is closest to the sub speaker connections. Before with the blown diode there was continuity between the +/- of that caps pads.
As long as I'm deep into this board are there any mods that would improve the sound of this amp? I'd love to figure out how to put tube minatures in somewhere to get a nice tubey sound.
My memory of those MC series amps is that they left little room for upgrades. Perhaps you might change out the input op-amps with AD or BB op-amps. I just did this today for a PG amp and it really changed the way the amp sound <for the better>
With the age of your amp I would possibly exchange all the outputs and see if you get a lower DC offset at the output, and don't be afraid to replace the power capacitors on the 12 volt side and the main rail for each channel.
There just isn't much else you might do, unless you find some more leaky or defective components.
The TIP 102 & 107 upgrade wont give you anything but the fact your using the highest grade of that series of transistor, But this couldn't hurt.
How many output pairs per channel ?
With the age of your amp I would possibly exchange all the outputs and see if you get a lower DC offset at the output, and don't be afraid to replace the power capacitors on the 12 volt side and the main rail for each channel.
There just isn't much else you might do, unless you find some more leaky or defective components.
The TIP 102 & 107 upgrade wont give you anything but the fact your using the highest grade of that series of transistor, But this couldn't hurt.
How many output pairs per channel ?
Parts came in yesterday: FED16s where the slightly higher rated ones he was talking about.
I thoroughly cleaned the board and carefully put in the parts. Brought it up slowly with a variac because I read it doesn't have a regulated ps and the caps are new. Works!! No fuses blew and the one channel I tried played fine.
I replaced all the caps at the beginning hoping that was it. I couldn't find Nichicon in the 1000uF 50V radial package. All I could get was Xircon which I know is crap. I did get a pair of TCI ones in the order but I don't know if these are any better. What does that pair of caps control? Should I try to get better caps or try to squeeze larger ones in there? Or no sonic benefit?
It has a 2 pairs of 102/107 per channel. So 8 pairs total.
I asked about changing the opamps but the tech said I might get into timing issues. There's 4 opamps on the underside of the board. Are those the ones you're talking about? T223TIPs.
There's 6 MTP25N06 RB2 on the power supply.
I'd love to do something. I'm impressed on the components they used. All high quality.
There's still something funky with the one hi-pass filter where I found a burned resistor but I use the head decks controls for that anyway.
I thoroughly cleaned the board and carefully put in the parts. Brought it up slowly with a variac because I read it doesn't have a regulated ps and the caps are new. Works!! No fuses blew and the one channel I tried played fine.
I replaced all the caps at the beginning hoping that was it. I couldn't find Nichicon in the 1000uF 50V radial package. All I could get was Xircon which I know is crap. I did get a pair of TCI ones in the order but I don't know if these are any better. What does that pair of caps control? Should I try to get better caps or try to squeeze larger ones in there? Or no sonic benefit?
It has a 2 pairs of 102/107 per channel. So 8 pairs total.
I asked about changing the opamps but the tech said I might get into timing issues. There's 4 opamps on the underside of the board. Are those the ones you're talking about? T223TIPs.
There's 6 MTP25N06 RB2 on the power supply.
I'd love to do something. I'm impressed on the components they used. All high quality.
There's still something funky with the one hi-pass filter where I found a burned resistor but I use the head decks controls for that anyway.
I did find out that the 1000uF 50V do supply the 4 channels. I can either get a audio grade cap in 1000uF 50V which is the same size as the 2200uF 50V or I could just put in the 2200uF 50V.
Would any of this make any sonic difference?
The amp is sounding rather thin and brittle. It could be the new Sony head unit which I don't care for... CDX 5715R
I know better ps caps in home audio result in a quieter less distortion presentation. Don't know if its overkill here.
Would any of this make any sonic difference?
The amp is sounding rather thin and brittle. It could be the new Sony head unit which I don't care for... CDX 5715R
I know better ps caps in home audio result in a quieter less distortion presentation. Don't know if its overkill here.
With the age of your amp I would upgrade the power supply caps just for principal that they don't last forever, and any extra energy storage would be only helpful, and the extra filtering is just a plus also.
As for op-amps the numbers you posted look like date codes not ID numbers look again to see all the printing on the the little 8 pin square blocks, Please?
I think they used TLO62 or72 or82 op-amps <all the same family just different grades> There all lots of better op-amps then those, as for timing issues, well I don't understand the reference with regard to audio but maybe I'm missing something
As for op-amps the numbers you posted look like date codes not ID numbers look again to see all the printing on the the little 8 pin square blocks, Please?
I think they used TLO62 or72 or82 op-amps <all the same family just different grades> There all lots of better op-amps then those, as for timing issues, well I don't understand the reference with regard to audio but maybe I'm missing something
Jaime has those dual transistors <the 3067> those are the diff input to the amp channel. Ampslab has them also, but higher cost. TLO72CP is the op-amp number, Easy to find and a better grade part would be TLO82.
If after replacing the outputs you still have a larger than expected DC offset at the output, then try and replace the 3067 dual transistor. They get damaged by being overdriven, and cause DC offset on the output to be higher than normal.
If after replacing the outputs you still have a larger than expected DC offset at the output, then try and replace the 3067 dual transistor. They get damaged by being overdriven, and cause DC offset on the output to be higher than normal.
OK. I measured the speaker output with my DMM. Once channel is below 20mV However the other three are high 42.2/45.6/46.3 Jaime said below 100mV is ok.
He thinks I'm just throwing parts at it because I don't have a scope to measure all the proper specs. He also said if I was going to a 082 I should go up to a OP275 as that would be better.
He thinks I'm just throwing parts at it because I don't have a scope to measure all the proper specs. He also said if I was going to a 082 I should go up to a OP275 as that would be better.
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