Advent 300 Rebuild: Let the jaws hit the floor, let the jaws hit the flooooor!
- Thread starter patfont
- Start date
rmoreau61
Well-Known Member
Thanks for the words of encouragement. Part of the buy is to figure out how to sell it on my wife! The family room is at capacity and I'm eyeing the living room.... May be time to start culling the herd. I feel like the 300 would pair up nicely with my Advent Minis, though... and I've got an excellent source of knowledge right here for the expected recap/rehab adventure.
rmoreau61
Well-Known Member
I was thinking more along the lines of "it is small and light and does not take up much space, maybe she won't notice it..." Admittedly, a pretty weak plan. Personally (especially after seeing pics in this and some of the other related posts), I believe it would be as elegant a work of art as any of the pieces on display in our shelves and mantle - plus we could get some killer iPod sound. That's it, I'm already improving my sales pitch! Thank you for the inspiration.
Welcome to AK! Sounds like a plan and I think you'l have a lot of fun. T. Holman helped make a number of great products.
rmoreau61
Well-Known Member
Not to mention the MA connection with H. Kloss and his history. I've come across Advent and KLH speakers as throw alongs with other equipment I've picked up. Still kick myself over giving away a hand me down AR XA turntable years ago (I thought CD's were the future). I still intend to right that wrong.... Indiana Jones would dope slap me for my blatant disregard for historical artifacts. I repent and am back with a vengeance!
Thanks for the welcomes!
Thanks for the welcomes!
GD70
Lunatic Member
Old thread I know, but my 300 that has been in my workshop for some years really needs some help, so I've decided to look after it this winter.
A few questions:
- The volume (and, noticably, the bass) is much lower in one channel than in the other. Would this be something that might be fixed by a recap? I.E. should I recap first and then look at other parts?
- I see you've used film caps in some locations (the signal path) and 'lytics elsewhere. Are the locations of the signal path caps identified somewhere so I can do the same?
- Is there a comprehensive list of caps for this thing somewhere? Does the version matter?
A few questions:
- The volume (and, noticably, the bass) is much lower in one channel than in the other. Would this be something that might be fixed by a recap? I.E. should I recap first and then look at other parts?
- I see you've used film caps in some locations (the signal path) and 'lytics elsewhere. Are the locations of the signal path caps identified somewhere so I can do the same?
- Is there a comprehensive list of caps for this thing somewhere? Does the version matter?
Ah thanks, did get the parts list from that site.
Will upgrade the 3000uF to 6800uF Nichicon if I can find them.
Can you answer the question about which locations/which caps?
I'm thinking/taking a WAG that the volume difference may be due to a faulty output transistor, but recapping first shouldn't actually hurt anything so should be OK. Maybe I'll test the outputs while I'm waiting for caps to arrive.
I'm kind of a trained monkey with a soldering iron and not so good at the circuitry stuff, so I don't think I can answer your questions re the locations. But yes, replacing the caps won't hurt. As I seem to recall my 300 was a little unbalanced before but better after and I did not replace any transistors. I did use larger caps in the PS, perhaps not 6800 but at least 4000.
Good luck with your 300 project, it is def worth a nice rebuild!
I have an AKers 300 here right now with low volume in the right channel and it turned out to be that one of the axial caps was bad. There were also other problems. To deem your 300 healthy check the voltages noted in the SM and if all are ok and bias is steady, it may indeed just be a bad cap.
hope this helps
I have an AKers 300 here right now with low volume in the right channel and it turned out to be that one of the axial caps was bad. There were also other problems. To deem your 300 healthy check the voltages noted in the SM and if all are ok and bias is steady, it may indeed just be a bad cap.
hope this helps
fred soop
Super Member
Anything in the signal path should be film, preferably polypropylene. If the capacitors to be replaced are too large for that, then electrolytics should be approximately 10 times the value needed for the low end of the bandwidth to bring distortion down to the noise floor (demonstrated by Douglas Self). Additionally, if the DC voltage across the capacitor is very low, such as an input coupling capacitor, then a non polarized type is preferable.
On an Advent 300, by and large, every 10uF cap and every 1uF cap is in the signal path. And though I'm not generally a proponent of broad-brush recapping, on this model I would indeed recommend replacing all of them. Don't forget to check the tuner board - in particular, replacement of the 1 uF axial caps near the MPX chip is warranted.
Hope this helps,
chazix
Hope this helps,
chazix
randyhouse
New Member
I just started on one. Recapped the power supply and am on my way with the rest. One question, how does one by pass the tone controls? It sounds like a great mod.
If you are going to use a very high quality amp with it, it does make an improvement. If you do the tone control bypass the loudness switch will still work. I have done it in the past it is a mechanical bypass and can be changed back. I like to leave the tone controls active, but that is the choice of the person who owes the unit.
