always good idea
Gremlins are never sleeping
I can replace and change everything, but if something happens to mine ultrarare speakers, I'm in deeeeeeep trouble
Gremlins are never sleeping
I can replace and change everything, but if something happens to mine ultrarare speakers, I'm in deeeeeeep trouble
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Roger that. Then again, your Tannoys are ultrarare darlings from Heaven. Maybe just take the risk, seeing as I don’t have speakers 
Or use shitty speakers… 
Or use shitty speakers…
naah
I have plenty of Tanns (15" and 12")
of course that it would be pity breaking them in any way, but they are replaceable
my RCA LC1B practically aren't
I have plenty of Tanns (15" and 12")
of course that it would be pity breaking them in any way, but they are replaceable
my RCA LC1B practically aren't
you're not the first one who asked the same
as old saying sez (literally translated from Serbian, I'm sure there is one in Engish having same meaning) - Luck follows brave ones ......
I wasn't brave, I was lucky ... and smart to recognize Nugget
as old saying sez (literally translated from Serbian, I'm sure there is one in Engish having same meaning) - Luck follows brave ones ......
I wasn't brave, I was lucky ... and smart to recognize Nugget
you're not the first one who asked the same
as old saying sez (literally translated from Serbian, I'm sure there is one in Engish having same meaning) - Luck follows brave ones ......
I wasn't brave, I was lucky ... and smart to recognize Nugget
Maybe something originating from Pasteur?
Forbes Quotes
Typical badass Batsch to replace chance with bravery
Recognize nugget = prepared
you're not the first one who asked the same
as old saying sez (literally translated from Serbian, I'm sure there is one in Engish having same meaning) - Luck follows brave ones ......
I wasn't brave, I was lucky ... and smart to recognize Nugget
You don't see it often - a bit archaic maybe, but it's 'Fortune favours the brave'.
Can someone speak more to the speaker protection? I'll be using this amp on a pair of Sonus Faber speakers I would very much not like to blow up!
Thiele/Small parametre for Tannoy 3859
Coil restistance 4.81 (ohm)
Force factor ( BL) 12.67 (newton/ampere)
Total suspension compliance 0.08 (millimetre/newton)
Moving mass 61.21(gm)
Mechanical resistance 9.57 (mechanical ohm)
Effective radiating area 804.85 (square centimetre)
Shove 33.36 (newton second/metre)
Resonant frequency 70.50 (hertz)
Mechanical Q 2.83
Electrical Q 0.81
Total Q 0.63
Sensitivity 96.23 (dB SPL/2.8 volt à 1m) à 20degC
Equivalent volume compliance 75.60 (litre) à 20degC
made for wedge monitors and Cougar small box
no bass to speak of, so it must be augmented with bass helper
ideal for biiiiiiiig OB, with one or 2 15" bass helpers per side
though, rejuvenation (or replacement) of cloth surround inevitable
There is a thread dedicated to that subject at,
Speaker Turn On Delay and DC Protector Board Set (V3)
Speaker protection circuits are well known to cause more problems with new builds, and especially new builders. They introduce extra complexity into what should be very simple connections, plus they require an extra small transformer. None of the First Watt amps sold by Nelson Pass include them. The Aleph J does include a simple built-in current limiter.
A simple start up delay circuit is shown in the power supply build guide by 6L6. It consists of a pair of thermistors connected to the primary windings of the power transformer. That is good to have to avoid blowing AC inlet fuses at power on. It works by slowing the rate at which the big capacitors are initially charged. The Aleph J needs a larger thermistor than the common CL-60. It is better to use the Amphenol 12D2-15. The old CL-60 is still useful as a ground loop breaker, where it doesn't need to carry steady state current.
Awesome, thank you both! I would plan to follow that build (and I think by extension, this one? DIY Aleph J: A Build Guide) Very helpful and especially the context. I will leave it as-is.
Oh boy, it just got real, USPS just dropped off the first batch of real parts, the amp chassis is waiting to board a plane in Milan, and the transformer has either shipped or is about to ship. I was almost hoping for some delays to help spread things out.
Oh boy, it just got real, USPS just dropped off the first batch of real parts, the amp chassis is waiting to board a plane in Milan, and the transformer has either shipped or is about to ship. I was almost hoping for some delays to help spread things out.
If you take care with your build, continue planning well, ensure solder work is good, and test the amp and let it run for a good while before connecting any speakers, specifically ensuring stable bias levels and low and stable DC offset, don’t worry too much about speaker protection. Unless you have unobtanium speakers
Edit: or if u use poorly matched MOSFETs and don’t watch dissipation 🙂
Me, I like a bit of risk Then again, I don’t have speakers…
Edit: or if u use poorly matched MOSFETs and don’t watch dissipation 🙂
Me, I like a bit of risk
Then again, I don’t have speakers…
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Do all you initial your listening testing/biasing with a cheaper pair of speakers. Only hook up the nice speakers once you're confident it's all working correctly.
If you want to add the speaker protection once you get everything else working correctly, go for it. I like this one
https://www.diyaudio.com/forums/gro...pfi8eukoHSkMioQ-1d55YXXsn5Jph9uI_ZSXzXfvJMY4w though I'm sure the one in the DIYaudio store works great too.
If you want to add the speaker protection once you get everything else working correctly, go for it. I like this one
https://www.diyaudio.com/forums/gro...pfi8eukoHSkMioQ-1d55YXXsn5Jph9uI_ZSXzXfvJMY4w though I'm sure the one in the DIYaudio store works great too.
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Once built, it flawless. (Building is a bit complicated cause there’s confusing information in the thread. But you should finf everything within reasonable effort)
I would plan on using 'disposable' speakers to get everything tested and adjusted...but what sort of risk is there of a part failing after, say, 500 hours and blowing up your speakers because of that part failure? I was not aware of amps failing in a way that blow up speakers (but I am hardly the expert, just never heard of it).
I am not putting a condom on the outputs before my first set of speakers burn out. Then I will wisen up, for sure. Just my way, in stead of learning the smartest way beforehand.
Canonken, what for example can happen is if a rail/half/part of the amp or one or more components fail, the DC offset can be severly affected, sending several volts of DC directly into the speakers. Voice coils don’t like that. Probably a terrible explanation, but basically that is more or less what can happen. A bunch of stuff CAN go wrong of course, as with everything in life.
You should do what you feel is best and safe enough for you. Doing it or not, it’s just risk management. It basically comes down to how much risk you willing to take. Risk being a result of likelyhood and consequence, where your chosen circuit plus your skills make up the likelyhood, and the consequence made up basically of dollars you are willing to loose should it go wrong.
I know prople who lost A LOT of money cuz of voice coil burnouts, expensive speakers, and not with DIY amps either. No one can decide for you what risk you are willing to take. Safest way is to use one.
Regards,
Andy
Canonken, what for example can happen is if a rail/half/part of the amp or one or more components fail, the DC offset can be severly affected, sending several volts of DC directly into the speakers. Voice coils don’t like that. Probably a terrible explanation, but basically that is more or less what can happen. A bunch of stuff CAN go wrong of course, as with everything in life.
You should do what you feel is best and safe enough for you. Doing it or not, it’s just risk management. It basically comes down to how much risk you willing to take. Risk being a result of likelyhood and consequence, where your chosen circuit plus your skills make up the likelyhood, and the consequence made up basically of dollars you are willing to loose should it go wrong.
I know prople who lost A LOT of money cuz of voice coil burnouts, expensive speakers, and not with DIY amps either. No one can decide for you what risk you are willing to take. Safest way is to use one.
Regards,
Andy
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