Thanks to both.
ZM, I would love to hear what you have to say as I would like to do something with them but am t ground zero. And you know. Hopefully we can get an on topic pass for this since Mr. Pass uses Tannoy 15in HPD's in special set up as listening monitors for all Pass Labs. Says they are very revealing for amplifier listening. Guess I'll just have to take my chances. Do you have them? Thought I saw a pic but might be from another person.
I hope you have weathered the "storm" well albeit at slowed rate. Are they returning to normal where you are?
Regards,
Don
ZM, I would love to hear what you have to say as I would like to do something with them but am t ground zero. And you know. Hopefully we can get an on topic pass for this since Mr. Pass uses Tannoy 15in HPD's in special set up as listening monitors for all Pass Labs. Says they are very revealing for amplifier listening. Guess I'll just have to take my chances. Do you have them? Thought I saw a pic but might be from another person.
I hope you have weathered the "storm" well albeit at slowed rate. Are they returning to normal where you are?
Regards,
Don
things are easing in my neck of wood..... hope there will not be second wave .....
regarding Tanns, you can find some amusing things on my blog, just type Tannoy in search box
regarding Tanns, you can find some amusing things on my blog, just type Tannoy in search box
guidance please, anyone
I went off the deep end and bought a pair of pre owned Tannoy HPD 385/8 Speakers with xovers. Basically, 15" DC Tannoy's. They say in very good condition. We'll see. I need to put them in a box and have no idea how to figure out what would give me the best result for our Pass DIY amplifier projects. Pointing me in the right direction would be greatly appreciated. My DIY project just went into a realm I wasn't thinking of.
Thanking everybody in advance.
Regards,
Don
I went off the deep end and bought a pair of pre owned Tannoy HPD 385/8 Speakers with xovers. Basically, 15" DC Tannoy's. They say in very good condition. We'll see. I need to put them in a box and have no idea how to figure out what would give me the best result for our Pass DIY amplifier projects. Pointing me in the right direction would be greatly appreciated. My DIY project just went into a realm I wasn't thinking of.
Thanking everybody in advance.
Regards,
Don
see on my blog what I made (I drew, other guy made) for 15" DC
if that suits you, counting on fact it can be little smaller, buzz me and I'll send you first important details for final decision,then plans if you say yay
if that suits you, counting on fact it can be little smaller, buzz me and I'll send you first important details for final decision,then plans if you say yay
I have finally received my Cinemag.
And I have powered one channel, it's working!
I have dumb questions (Ohm low level), but I'll sleep better after confirmation.
Am I correct saying that 1A8 is reached with 210mV across negative PS resistor when that resistor is four parallel 0R47 ?
What is a nice offset, below 20mV?
And I have powered one channel, it's working!
I have dumb questions (Ohm low level), but I'll sleep better after confirmation.
Am I correct saying that 1A8 is reached with 210mV across negative PS resistor when that resistor is four parallel 0R47 ?
What is a nice offset, below 20mV?
4 x 0R47 in parallel is 0R1175
so U=I x R , = 1A8 x 0R1175= 0V2115
be sure to have final Iq set at temp equilibrium , and be sure to re-set DC Offset after removing temporary inserted monitoring resistor
if you're monitoring Iq at permanent resistor (in CRC) , you're done at once
so U=I x R , = 1A8 x 0R1175= 0V2115
be sure to have final Iq set at temp equilibrium , and be sure to re-set DC Offset after removing temporary inserted monitoring resistor
if you're monitoring Iq at permanent resistor (in CRC) , you're done at once
Both channels are alive and cooking nicely.
Dead easy to adjust, and offset stays extremely low when adjusted. Beautiful beast.
Pretty significant positive tempco, bias is raising of 150 mA at temp equilibrium 😉
ZM, the silkscreen says 21 mA for the input buffer bias, and you write 20 elsewhere, I believe the difference is not significant at all?
And where would you tap for power leds, directly at the PSUs, or on the amp PCB, like at the output of the 7805?
Dead easy to adjust, and offset stays extremely low when adjusted. Beautiful beast.
Pretty significant positive tempco, bias is raising of 150 mA at temp equilibrium 😉
ZM, the silkscreen says 21 mA for the input buffer bias, and you write 20 elsewhere, I believe the difference is not significant at all?
And where would you tap for power leds, directly at the PSUs, or on the amp PCB, like at the output of the 7805?
mine had lower TempCo, what you're using ini between mosfets and heatsink, and how big heatsink is ?
anyway, nothing to worry about
20 or 21mA, irrelevant; frankly , can't remember that I put that info on pcb silkscreen?
LED - tap on PSU pcb, for resistor use 1K per each rail V , ignore exact calculus, so 22K it is
anyway, nothing to worry about
20 or 21mA, irrelevant; frankly , can't remember that I put that info on pcb silkscreen?
LED - tap on PSU pcb, for resistor use 1K per each rail V , ignore exact calculus, so 22K it is
It's 4U from Gianluca. And red Keratherm.
I'm tweaking bias to 1A9 at equilibrium. I'll check temp later, sinks are hot but not burning hot.
And thanks for the LED tip!
I'm tweaking bias to 1A9 at equilibrium. I'll check temp later, sinks are hot but not burning hot.
And thanks for the LED tip!
Ran into Sissy trouble - the DiyAudio speaker protection circuit got triggered and there isn't any sound on the amp. I did a quick check on the DC offsets before the protection module and found the left channel is ~500mV but the right was hoovering around 10V. Not good.
Before I disassemble anything, is there any quick tests that i can try to find the offending culprit?
Before I disassemble anything, is there any quick tests that i can try to find the offending culprit?
first thing to check - is there 5V from 7805
after that, regular things - check for cold solder joints, and - most important - how's eeny 9140 looking - still isolated from heatsink, and still firmly bolted to, and still alive
twiddle trimpots for 1/8 turn forth and back , and if that solve the thing, replace them ( re-setting everything, logically)
these days all brands of trimpots are equally trustworthy
I was fixated on Bourns, but after few bad ones ditto from package, started to ignore brand, while proceeding with checking each (before soldering or sending to someone else)
after that, regular things - check for cold solder joints, and - most important - how's eeny 9140 looking - still isolated from heatsink, and still firmly bolted to, and still alive
twiddle trimpots for 1/8 turn forth and back , and if that solve the thing, replace them ( re-setting everything, logically)
these days all brands of trimpots are equally trustworthy
I was fixated on Bourns, but after few bad ones ditto from package, started to ignore brand, while proceeding with checking each (before soldering or sending to someone else)
Thanks ZM. I will probe the points. Hopefully leaving the channel amp on with this defect isn't going to kill it further.
Indeed. Cinemag is back in production. 🙂make some Eu based guy happy
let Yanks deal on their side of Big Pond
I ordered my CineMags back in march just before they were shut down. Received them 2days ago. I talked with Dave who was always really nice. It was not an easy restart for them. They are about 60mi from me. 2 days total transit time.
Yea, we can probably go direct on this side of the pond😀
Now I have to wait for Antek's🙁🙁🙁
Don
I started to probe the amp boards without powering up to find shorts. Nothing different against the working channel.
Decided to power up the amp again, and I realized that the LED for V+ rail is not lighting up. How did I miss that, too embarrassed to share now.
The culprit was a bad crimp connector at the transformers. Replacing it did the trick, music is flowing again, the Sissy is definitely missed. Thanks ZM for the tips.
(that's why I'm soldering everything - had too much thingies in repair with troubled connectors; though, can't argue with that, that was money I lived of 🙂 )
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