johnsonwu

Responses from johnsonwu

My Amp is Broken - Not Sure What to Do - Any Recommendations?
I have a Thermaltrak equipped HD220 myself and Audio Research would ABSOLUTELY refuse to return my repeated calls AND repeated emails.  The good old days of Leonard and Kalvin are gone.A $25/hr tech... GOOD LUCK finding one who knows what the 5 pi... 
My Amp is Broken - Not Sure What to Do - Any Recommendations?
Here’s the problem with ThermalTrak devices that supposedly was solve by Ayre but not AR https://www.stereophile.com/solidpoweramps/407ayre/index.htmlON Semi only made 1 set of thermaltraks, and yes I just confirmed that Mouser has them in stock.B... 
My Amp is Broken - Not Sure What to Do - Any Recommendations?
Ralph the OP was referring to thermaltrak output chips made by OnSemi.  Can’t be bypassed.  They were discontinued for a while. Now back inthe market.   
My Amp is Broken - Not Sure What to Do - Any Recommendations?
You can still get thermaltrak chips on mouser or digikey last I checked.   
Review: JM Labs Diva Utopia Be Speaker
I am assuming you didnt detect and harhness/brightness immediately after the mod like  llkmi7 observed right? 
Review: JM Labs Diva Utopia Be Speaker
You should not be hearing a tonal shift towards the highs unless there's an issue with wiring the resistor.  Have you also checked the outer foil/inner foil orientation of the VCap?Also try not to use electrical tape, use heat shrink tubes or nylo... 
Hard Audio - Ceramic Speakers
The old accuton midrange C90-6-079 used in a lot of commercial offerings sure conveys a cold and dry sound especially when playing violins.  The newer C90-6-724 delivers a marked improvement right out of the box.  Requires a slight attenuation if ... 
Y No YG ?
I'm fortunate enough to own both the YG Hailey and Avalon Eidolon Diamond and I swap between the 2.  IMO both speakers belong to the "modern" "cool" school of sound.  The YGs sound like electrostats when playing easy programs at moderate volumes, ... 
Review: JM Labs Diva Utopia Be Speaker
If you don't do the woofer inductor mod then stick with 180uf unless you hear a midbass suckout in that case the subwoofer doesn't cross well in the room and you will need to get the midbass to play lower by using a 220uf. The 440uf lytic, ok to p... 
Martin Logan Tweaks / Upgrades
Open the box and trash the junk crossover parts and use reasonable audio grade substitutes.  An inductor, a resistor, and 2 caps are what you need.    
High Quality bi-amp-able full range speakers - choices?
Hi Aigenga,The EOS uses an Accuton ceramic tweeter that sounds very dry.Pop it open and replace the coupling cap with a Jensen copper foil or VCap oil to tame it and replace the attenuating resistor with a Mills Non-inductive wirewound.  You willb... 
High Quality bi-amp-able full range speakers - choices?
Just recap the EOS tweeter to neutralize that cool ceramic sound and be happy.   It will be hard to find a pair of speakers that images as well as the EOS 
Counterpoint - Alta Vista - Mike Elliott
I have the schematics and I have serviced no less than 5 of them.Most of them have failures like popping caps, rustling plate resistors, blown rectifier 6CA4 and blown Zeners.Why would anyone take out 3 valves?  I assume they are the 12AX7 error a... 
Considering switching from Audio Research to PrimaLuna, troube with VS115 amp
Resistor blowing due to a runaway tube (age or mfg defect) is a common problem. Unless you have VAC phis that have thermal tube sentry circuit you will always run into it. Nothing wrong with audio Research. Just ignore what most people say and rep... 
How much does tube brand REALLY affect sound in terms of rectifier tubes?
Bigkidz if your preamp has a regulator after the rectifier then changing the rectifier won’t change much. If it’s a classic design LCRC filtered then I would expect you to easily be able to hear it. Also I think getting slightly different tubes e....