Canuck Audio Mart Hifi and Audio ForumCanuck Audio Mart Hifi and Audio Forum
It is currently Sat Dec 16, 2017 1:22 am

All times are UTC - 8 hours




Post new topic Reply to topic  [ 29 posts ]  Go to page Previous  1, 2
Author Message
PostPosted: Mon Sep 07, 2015 12:55 pm 
Offline

Joined: Sun Oct 13, 2013 1:57 pm
Posts: 81
Location: Burnaby, BC, CA
hifijones wrote:
milag wrote:
Too bad some of those french manufacturers leave their customers in the dust.
I'am thinking Audiomat also, pretty bad for anything more complicated than a tube replacement.


Micromega was legendary for poor product support back in the '90s. The majority of their problems could be traced to the infamous/cursed Philips CDM12.4 transport used in many of their CD players and transports. They essentially stonewalled customers and simply referred the problem to Philips, which also did very little to take care of the problem.

As a result of that debacle, there was no importer/distributor for Micromega components in N. America for many years. There may have been other factors involved as well but crappy support from the factory will torpedo a companys' good fortunes pretty quickly.

What I find hard to believe is that YBA no longer has any distribution in N. America. Plurison used to be the distributor in Canada and in the US it was Audio Plus Services in Champlain, NY. I guess they lost their mojo somehow. It seemed as though Sam Tellig singlehandedly kept the YBA doors open for decades with his glowing product reviews in Stereophile.


Yeah, American companies would never do that LOL!

Shall we start a list?


Top
 Profile  
Reply with quote  
PostPosted: Mon Sep 07, 2015 4:15 pm 
Offline
User avatar

Joined: Wed Apr 28, 2010 2:00 pm
Posts: 3022
Location: Rio Rancho, NM, US
I never said American companies have never nor would ever treat their customers like that. I'm sure that many companies would act in an equally irresponsible manner when faced with a similar situation. Especially one that greatly affects the bottom line: money & profits.

I was just relating some known and documented behavior by a French manufacturer. milag started it; I was just piling-on. :lol:

_________________
I think, therefore I am not sure.


Top
 Profile  
Reply with quote  
PostPosted: Mon Sep 07, 2015 4:47 pm 
Offline

Joined: Mon Jan 31, 2005 8:37 am
Posts: 503
Location: Quebec, QC, CA
If we were to buy direct from the manufacturers, at least the distributor and retailer would no longer have the excuse of "no longer carrying the line" in not having to service the product they sold years ago, or even months ago in some cases.

But then we could no longer audition product before buying some will say.

Well, that opportunity to listen at a dealer does cost us dearly.


Top
 Profile  
Reply with quote  
PostPosted: Mon Sep 07, 2015 5:02 pm 
Offline

Joined: Mon Jan 31, 2005 8:37 am
Posts: 503
Location: Quebec, QC, CA
hifijones wrote:
I never said American companies have never nor would ever treat their customers like that. I'm sure that many companies would act in an equally irresponsible manner when faced with a similar situation. Especially one that greatly affects the bottom line: money & profits.

I was just relating some known and documented behavior by a French manufacturer. milag started it; I was just piling-on. :lol:


Well, I have been trested pretty badly myself by both manufacturer and dealers - twice actually, both times canadian in origin too.


Top
 Profile  
Reply with quote  
PostPosted: Mon Sep 07, 2015 9:06 pm 
Offline
User avatar

Joined: Wed Apr 28, 2010 2:00 pm
Posts: 3022
Location: Rio Rancho, NM, US
I'd like to clarify my previous remarks about YBA. In no way was I trying to link poor representation and/or service from Plurison and Audio Plus Services to the fact that YBA is no longer distibuted in N. America.

In fact, nothing could be further from the truth. I can't speak specifically regarding Plurison as I had no experience with them. But I did have extensive experience with Audio Plus Services because I worked for a YBA dealer for several years and the factory support from them was top-notch.

In fact they were one of the absolute finest of all of the distributors that I dealt with as Service Manager. Professional, friendly, courteous to a fault and they always did exactly what they were supposed to do. And most importantly, they accomplished all this in a realistic and manageable time frame. I have no reason to believe that Plurison was any different.

So I doubt seriously that the reason that YBA lost their distribution in Canada and the US has anything to do with product and factory support from a vendor/customer service point-of-view. YBA gear rarely needed service anyway.

_________________
I think, therefore I am not sure.


Top
 Profile  
Reply with quote  
PostPosted: Tue Sep 08, 2015 4:19 am 
Offline

Joined: Sun Apr 17, 2005 6:49 am
Posts: 597
Location: ., AB, CA
dtsaudio wrote:
I've serviced a number of these. There is NO service manual or schematic available. YBA never gave them out. However they are a pretty simple amp and any tech who can't figure it out shouldn't be working on this stuff.
The caps do fail occasionally in these amps, but if it isn't humming that is not likely the problem. There are no caps in the signal path.
The way these amps were designed is that the bias is set fairly low, and they use the warm-up to get rid of crossover distortion. Cold they exhibit a noticeable crossover notch on a scope that is clearly audible. Warmed up it should disappear. About 30 minutes is necessary. If bias is out, it should be set after an hour or so of running at idle. The heat sinks should get warm, but not hot. Too high a bias and the amp will start to run away and boom!
Also should the caps need to be changed, they have a non-standard footprint and it may be necessary to modify the board a bit to make the new ones fit.
That's all the trade secrets I'm giving out.


Thanks very much Dan - that is very valuable info. I am just assuming a recap is in order - but there is no hum whatsoever - so maybe it is a bias adjustment as you mention.
Given that Plurison also does have original parts for the amp and they also know it well and have worked on mine before - I think I am leaning to sending back to them for a good once over and not worry about the shipping costs.

Thanks everyone
jp


Top
 Profile  
Reply with quote  
PostPosted: Tue Sep 08, 2015 5:46 am 
Offline
User avatar

Joined: Wed Apr 28, 2010 2:00 pm
Posts: 3022
Location: Rio Rancho, NM, US
J. P. wrote:
Given that Plurison also does have original parts for the amp and they also know it well and have worked on mine before - I think I am leaning to sending back to them for a good once over and not worry about the shipping costs.


Or you could send it to Dan and let him fix it. :) Either way, once you get it squared away, I'd leave it on all the time. Or if the hydro usage concerns you, take Dan's excellent advice and turn it on 30 minutes ahead of time, throw on a CD and let it warm up musically before you sit down in the sweet spot for a serious/critical listening session.

_________________
I think, therefore I am not sure.


Top
 Profile  
Reply with quote  
PostPosted: Tue May 23, 2017 1:32 pm 
Offline

Joined: Sun Apr 17, 2005 6:49 am
Posts: 597
Location: ., AB, CA
Thought I would update this thread - After getting the caps redone at Plurison in Sept of 2015 (as they had the exact replacements being the former Canadian distributor) the issue was still not solved. So I left it boxed up until now, when I decided to chat via email with Dan Santoni (DTS Audio). Based on Dan's online diagnosis, I boxed it up and shipped it off to him May 8 via Canada post. He received it on a Friday May 12 (not bad for Canada Post Airdrie to Hamilton) and had it re-biased that afternoon and monitored it over the weekend to see if the bias might drift and then boxed it back and shipped it back Tuesday May 16. It arrived today.
So those of us who need some work done and cant find a suitable tech - my advice is to ship it to Dan and have him work his magic.
Absolutely excellent service !!!!!! My amp is singing like it is supposed to now thanks to Dan.
Cheers
Jim


Last edited by J. P. on Wed May 24, 2017 2:58 pm, edited 1 time in total.

Top
 Profile  
Reply with quote  
PostPosted: Tue May 23, 2017 1:56 pm 
Offline
User avatar

Joined: Sun Sep 10, 2006 2:07 pm
Posts: 4502
Location: Welland, ON, CA
J. P. wrote:
Thought I would update this thread - after chatting via email with Dan Santoni (DTS Audio) I boxed it up and shipped it off to him May 8 via Canada post. He received it on a Friday May 12 (not bad for Canada Post Airdrie to Hamilton) and had it re-biased that afternoon and monitored it over the weekend to see if the bias might drift and then boxed it back and shipped it back Tuesday May 16. It arrived today.
So those of us who need some work done and cant find a suitable tech - my advice is to ship it to Dan and have him work his magic.
Absolutely excellent service !!!!!! My amp is singing like it is supposed to now thanks to Dan.
Cheers
Jim


Yep, Dan's abilities have been well documented in the CAM forums throughout the years, but it definitely bares repeating at regular intervals.

Happy to hear your amp is back in shape. Owned some YBA electronics at one time. Unfortunately someone saw fit to relieve me of their ownership without my permission.

_________________
Just because you're paranoid doesn't mean that they're not out to get you.


Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 02, 2017 11:53 am 
Offline

Joined: Sat Sep 02, 2017 11:40 am
Posts: 1
Location: Victoria, BC, CA
I received a YBA Integre DT for repair complaining of hum and "clicking". One channel appears fine, the other (left) almost immediately took out a fuse inline with my bench speakers when I turned it up a tiny bit; these appear to have no protection circuit. Checked semiconductors and all seem OK to the output, fired it up again and the channel appears to DC the speaker line when volume control is turned. Scoped both channels at the output and both appeared to work with speakers disconnected; increased volume and the bad channel DCs like crazy. I suspect either bad (or dirty) control (cleaning through the side made no difference) or possibly a capacitor, although I see no audio at any easily accessible capacitor lead.

No schematic available according to Google or this thread, Plurison no longer distributes in Canada. Any suggestions? Thank you kindly.


Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 02, 2017 1:36 pm 
Offline
User avatar

Joined: Mon Sep 26, 2011 8:33 am
Posts: 52
Location: Gatineau/Ottawa, QC, CA
Hi, at Québec City you could find the Audiotech from the store Audiolight at 418-687-9252.

They fix my YBA in the pass...Good luck!

https://magasinaudiolight.com/

Steve


Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 02, 2017 2:09 pm 
Offline

Joined: Sun Apr 17, 2005 6:49 am
Posts: 597
Location: ., AB, CA
I don't believe that YBA ever produced schematics or service manuals for these. Sorry I cannot help you out as I sent my amp to Dan Santoni (DTS Audio) in Hamilton an he fixed mine perfectly and very quickly as well.
Good luck
jp


Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 02, 2017 5:44 pm 
Offline
Dealer/Sponsor

Joined: Tue Jun 14, 2016 8:33 am
Posts: 1183
Location: Kingston, ON, CA
Hytekfred wrote:
I received a YBA Integre DT for repair complaining of hum and "clicking". One channel appears fine, the other (left) almost immediately took out a fuse inline with my bench speakers when I turned it up a tiny bit; these appear to have no protection circuit. Checked semiconductors and all seem OK to the output, fired it up again and the channel appears to DC the speaker line when volume control is turned. Scoped both channels at the output and both appeared to work with speakers disconnected; increased volume and the bad channel DCs like crazy. I suspect either bad (or dirty) control (cleaning through the side made no difference) or possibly a capacitor, although I see no audio at any easily accessible capacitor lead.

No schematic available according to Google or this thread, Plurison no longer distributes in Canada. Any suggestions? Thank you kindly.


sounds like it might be a leaky servo capacitor.

Dan mentioned the amp is apparently..Dc coupled, low bias. Which probably means a servo circuit.

Which probably means a large value low voltage cap?

If you shotgun-swap all the small signal low value caps in the channel, you might catch it. Not very much in the way of intelligence applied but it sometimes has to go that way when confronted with the given mystery.

If that does not catch it, you are probably down to any given associated diode junctions (transistor or diode)..and if not that...iffy traces-resistors-solder junctions.

_________________
(Ken Hotte, of) Teo Audio


Top
 Profile  
Reply with quote  
PostPosted: Sat Sep 02, 2017 8:11 pm 
Offline
Dealer/Sponsor
User avatar

Joined: Tue Feb 28, 2006 5:40 am
Posts: 458
Location: Hamilton, ON, CA
No servo. It relies on carefully matched input transistors and uses a cap to ground on the feedback.

How much DC are you measuring at the output with and without a load? It makes a big difference in tracking this down.
Check the voltages at the two differential pairs in each channel and carefully compare them. If you have any drift at all there you can have a few volts offset at the output.
Also there are 5 small electrolytic capacitors per channel. Four of them are local filtration. You can tell which ones, as they are next to each other in pairs. The fifth is part of the feedback circuit. If it is shorted or leaky you will have some DC.
If the DC is approximately half the rail or greater you have either a bad output or driver transistor. Easy enough to tell also if you scope it under load.
Check also the rectifiers. Since this is a DT, make sure both sets of rectifiers are outputting the same voltage.

_________________
Dan Santoni
http://www.dtsaudioelectronics.com


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 29 posts ]  Go to page Previous  1, 2

All times are UTC - 8 hours


Who is online

Users browsing this forum: No registered users and 6 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group