Marantz Transistor/Diode/Trimmer Sub Guide
- Thread starter Steven Tate
- Start date
alschmucker
Active Member
SE6021 Datasheet, Equivalent, Cross Reference Search
Type Designator: SE6021
Material of Transistor: Si
Polarity: NPN
Maximum Collector Power Dissipation (Pc): 0.3 W
Maximum Collector-Base Voltage |Vcb|: 80 V
Maximum Collector-Emitter Voltage |Vce|: 80 V
Maximum Emitter-Base Voltage |Veb|: 6 V
Maximum Collector Current |Ic max|: 1 A
Max. Operating Junction Temperature (Tj): 125 °C
Transition Frequency (ft): 250 MHz
Collector Capacitance (Cc): 15 pF
Forward Current Transfer Ratio (hFE), MIN: 100
Noise Figure, dB: -TO106
SE6021 Transistor Equivalent Substitute - Cross-Reference Search
May be this helps
Type Designator: SE6021
Material of Transistor: Si
Polarity: NPN
Maximum Collector Power Dissipation (Pc): 0.3 W
Maximum Collector-Base Voltage |Vcb|: 80 V
Maximum Collector-Emitter Voltage |Vce|: 80 V
Maximum Emitter-Base Voltage |Veb|: 6 V
Maximum Collector Current |Ic max|: 1 A
Max. Operating Junction Temperature (Tj): 125 °C
Transition Frequency (ft): 250 MHz
Collector Capacitance (Cc): 15 pF
Forward Current Transfer Ratio (hFE), MIN: 100
Noise Figure, dB: -TO106
SE6021 Transistor Equivalent Substitute - Cross-Reference Search
May be this helps
I am restoring a 2270 and have been ordering the parts. When it came to the power transistors the MJ21194 NPN was not in stock at Digi-key or Mouser. Kept looking and found that Mouser stocks these: MJ21195G (PNP) and MJ21196G (NPN). The specs are identical to the 93 &94 parts. Thought it may be something to add to the sub list. New to AudioKarma but it has been an immense help preparing for my rebuild.
Thanks everyone!
Thanks everyone!
part. Same part otherwise. 
Hey all,
So I have a 4230 here that I've been working on for quite a while now. I'm finally making some progress however I seem to have an issue with H704/H705 on the power amp boards. I've seen substitutions for the 2SC1318 that was originally in that place as KSC2690 (which doesn't fit without drilling the holes larger, which I'd like to avoid for now) and KSC2383.
When I have a KSC2383 in that position, the amp goes into heavy oscillation and would basically burn up if I didn't have it on a current limited power supply. I've tried both the O gain and Y gain KSC2383 with the same results.
If I use a 2n4401 in that spot, it works perfect however I don't like having to bend the leads up all funny. is there a better sub I should be using? I've searched all over this site and the web and haven't come up with much.
So I have a 4230 here that I've been working on for quite a while now. I'm finally making some progress however I seem to have an issue with H704/H705 on the power amp boards. I've seen substitutions for the 2SC1318 that was originally in that place as KSC2690 (which doesn't fit without drilling the holes larger, which I'd like to avoid for now) and KSC2383.
When I have a KSC2383 in that position, the amp goes into heavy oscillation and would basically burn up if I didn't have it on a current limited power supply. I've tried both the O gain and Y gain KSC2383 with the same results.
If I use a 2n4401 in that spot, it works perfect however I don't like having to bend the leads up all funny. is there a better sub I should be using? I've searched all over this site and the web and haven't come up with much.
By "current limited power supply" do you mean a DBT? The 4230 dislikes DBTs very much.
I actually ended up taking the amp boards out of the chassis and connecting them to a bench power supply when I was attempting to isolate the problem.
Is the KSC2383 something you've (or anyone else reading this?) used with success in the positions I've mentioned?
Steven Tate
CEO Flat Forehead Soc.
If you do a search on 2SC1318 in the Marantz section, you will see that lots of people have had success with KSC2383YTA as a sub over several models. However, success in one application does not mean it is a guaranteed good sub in all applications. These sub suggestions are starting places that seem to work 90% of the time. But you definitely need to be vigilant and make sure your particular circuit is not going to behave badly with one of these subs.
Thanks, yeah I've spent hours searching AK, diyaudio, etc. I do see the references to 2SC1318 but I've not found anything about it in this specific position on a 4230. In fact I haven't found any posts from people who have successfully replaced those transistors with anything. Just a lot of second hand "this should work" info.
And I get what you're saying about being vigilant about understanding the circuit it's in (Which I'm trying to do - I've spent an ungodly amount of time learning about amplifier circuits, bought several books, etc, but at the end of the day I'm not an EE, and this thing's not worth paying someone $1200 to restore, so it would end up being scrapped)
At this point I guess I'll leave the unsightly 2n4401's in there, since they work.
Steven Tate
CEO Flat Forehead Soc.
Looking at the specs of the 2N4401 vs. 2SC1318, they look very comparable. I may replace the KSC2690 with 2N4401 as the second sub since it is much closer in specs.
Yamaha5000
Never settle for 2nd best
What bench power supply did you use? I need + and - 50vdc at 5a
Newbie62
New Member
I am brand new to AudioKarma site. This is exactly what I was looking for! I am brand new to restoring audio equipment. I bought a Marantz 1070 back in 1975 with my paper route money. I traded up to a Marantz quadraphonic unit a couple of years later. Anyway, I bought a used 1070 on ebay many years back for around $120. It worked. Now it does not and I am going to try to fix it. This list is absolutely what I need! I was trying to cross reference the parts from the 1970s and was having a difficult time of it. Thanks!!!
Steven Tate
CEO Flat Forehead Soc.
Glad it looks helpful! Be aware that not all listed subs will work in every application. But, for the most part, they are subs that have been reported to work by someone on AK. Good luck!
Welcome to AudioKarma. Let us know how the restoration works out for you.
Has anyone found a good replacement for Q401 Q402 on a marantz 1120 power supply board?
They are listed as
S33369 & S33370
I can’t find any info on such animals and mine are blown for some reason. I might need a bucket of them until I find the reason they are popping.
They are listed as
S33369 & S33370
I can’t find any info on such animals and mine are blown for some reason. I might need a bucket of them until I find the reason they are popping.
I need to open the unit up, but based on some pictures I took at the time, I'm relatively certain I replaced the SE6021 and 2N4356 combo in the Model 33 headphone amplifier with ZTX851/951, mostly due to their very low noise figure (see tests here)
I'd be tempted to use the same combo in my Model 32, but Mouser doesn't have have them on stock (or @ocdecio's suggestion) and the classic BCs don't seem to have enough collector current to make them safe. I think I'll got with a KSC2383YTA in this case. If I'm reading this right, it should be a sort of pass device, so this should work.
@ducati2 I've successfully replaced SS33369 with 2N2219A and SS33370 with 2N2905A in my Model 33.
I'd be tempted to use the same combo in my Model 32, but Mouser doesn't have have them on stock (or @ocdecio's suggestion) and the classic BCs don't seem to have enough collector current to make them safe. I think I'll got with a KSC2383YTA in this case. If I'm reading this right, it should be a sort of pass device, so this should work.
@ducati2 I've successfully replaced SS33369 with 2N2219A and SS33370 with 2N2905A in my Model 33.
