Hi,
First question... when the UCD700 or alike will be available and for wich price ? i have to drive some 15" and the Ucd400 is perhaps a little limited for 15".
First question... when the UCD700 or alike will be available and for wich price ? i have to drive some 15" and the Ucd400 is perhaps a little limited for 15".
Hi Pa,
Not yet started with the UcD700, to busy with some interesting OEM customers 😀
Will be something for the end of this year.
For the moment you have to live with the UcD400, you can use two of in bridge?
Regards,
Jan-Peter
Not yet started with the UcD700, to busy with some interesting OEM customers 😀
Will be something for the end of this year.
For the moment you have to live with the UcD400, you can use two of in bridge?
Regards,
Jan-Peter
Maybe you should test first to see if 400 W is enough? The difference between 400 and 700 watts is only 2.43 dB in sound level.
Hi !
thanks for your answers...
i'hope Oem will sign, they would be silly not doing it 🙂
yes, 200 watts into 8 ohms (ucd400) is far enough in terms of sound level or concerning the output voltage, but a 15" need a lot of current to work well, i'have several 100 watts amps and when connected to the 15" the only thing you can have is noise, i think they can't drive the speaker due to the inductance effect of the speaker.
thanks for your answers...
i'hope Oem will sign, they would be silly not doing it 🙂
yes, 200 watts into 8 ohms (ucd400) is far enough in terms of sound level or concerning the output voltage, but a 15" need a lot of current to work well, i'have several 100 watts amps and when connected to the 15" the only thing you can have is noise, i think they can't drive the speaker due to the inductance effect of the speaker.
Hi...
What will be a suitable voltage (AC) for the UcD700 and UcD1000?
I'm hunting parts for a future PSU for these amps, and I found a batch of 1400VA transformers that might come in handy... 🙂
/Stefan
What will be a suitable voltage (AC) for the UcD700 and UcD1000?
I'm hunting parts for a future PSU for these amps, and I found a batch of 1400VA transformers that might come in handy... 🙂
/Stefan
Stefan,
The maximum voltage of the UcD700 (1000) will be something about 85VDC. The max. AC voltage +/-60VAC.
Regards,
Jan-Peter
The maximum voltage of the UcD700 (1000) will be something about 85VDC. The max. AC voltage +/-60VAC.
Regards,
Jan-Peter
Hi Jan-Peter,
When is the UcD700 expected to surface 🙂
If used with a 45V AC toroid, how much power can I expect (at 8 ohm)?
When is the UcD700 expected to surface 🙂
If used with a 45V AC toroid, how much power can I expect (at 8 ohm)?
Hi Duck-Twacy,
The UcD700 (or more) will be released before summer.
Power in 8 ohm: 45V-10%=41,5V --> (41,5^2)/8=215W
Jan-Peter
The UcD700 (or more) will be released before summer.
Power in 8 ohm: 45V-10%=41,5V --> (41,5^2)/8=215W
Jan-Peter
Duck-Twacy said:Hi Jan-Peter,
When is the UcD700 expected to surface 🙂
If used with a 45V AC toroid, how much power can I expect (at 8 ohm)?
The UcD400 will work perfectly fine with a 45V transformer and 8 ohms, and even 4 ohms. The UcD700 would offer no more if this is what you intend using for your power supply and you have 'normal' speakers. To take advantage of the next UcD level up from 400 you need to use a higher voltage, or use a silly load like 2 ohms.
I thought that 45V AC was rather on the edge for the UcD400. AC from the wall outlet can easily be 10% higher than nominal 230V.
And I just happen to have 45V toroids.
And I just happen to have 45V toroids.
I guess it depends how tight your mains voltage is. I'm going to use 45V and twin 'block' bridge (so 2.2V drop per secondary) PSU, so will be seeing just under 67V worst case. Just inside the 68V limit on the UcD400 🙂 Could be a problem at light loading and high mains times, but will just have to see...
Richie,
Am I reading this correct?
Using a single bridge rectifier block, the AC to DC gain is 1.41 - now you are talking a drop of 2.2V with 2 rectifiers?
Can you please explain this further?
Thanks! 😀
Am I reading this correct?
Using a single bridge rectifier block, the AC to DC gain is 1.41 - now you are talking a drop of 2.2V with 2 rectifiers?
Can you please explain this further?
Thanks! 😀
Each diode in a standard block rectifier has a voltage drop, the GBPC3502 I'm using has 1.1V per diode. This drop actually seems pretty typical of most block rectifiers. As I'm using a full block rectifier per secondary the current has to pass through two diodes on its travels.
At worst case the AC will be 10% higher.
DC = ((AC * tolerance) - Vdiode) * sqrt(2)
= ((45 * 1.1) - 2.2) * 1.414
= 66.88V
If you were to use just one bridge per whole transformer you would be over the limit for the UcD400 as only one diode is used per cycle:
= ((45 * 1.1) - 1.1) * 1.414
= 68.44V
🙂
I have overlooked the regulation of the transformer in these examples. If it is only lighly loaded then it is likely that these voltages will be exceeded. However, I believe that in Europe, former 220V countries actually have +7% tolerance on the 230V putting them in a better position to us Brits with 230V +10%. So in Europe you may be OK with 45V secondaries if you use a bridge per secondary.
At worst case the AC will be 10% higher.
DC = ((AC * tolerance) - Vdiode) * sqrt(2)
= ((45 * 1.1) - 2.2) * 1.414
= 66.88V
If you were to use just one bridge per whole transformer you would be over the limit for the UcD400 as only one diode is used per cycle:
= ((45 * 1.1) - 1.1) * 1.414
= 68.44V
🙂
I have overlooked the regulation of the transformer in these examples. If it is only lighly loaded then it is likely that these voltages will be exceeded. However, I believe that in Europe, former 220V countries actually have +7% tolerance on the 230V putting them in a better position to us Brits with 230V +10%. So in Europe you may be OK with 45V secondaries if you use a bridge per secondary.
Hi,
What do you plan on doing about that, turning it up, or just trusting that a 10% surge is a rare occurance? A TVS might be enough, would be cool to squeeze every last bit out of it.
Regards
I have overlooked the regulation of the transformer in these examples. If it is only lighly loaded then it is likely that these voltages will be exceeded.
What do you plan on doing about that, turning it up, or just trusting that a 10% surge is a rare occurance? A TVS might be enough, would be cool to squeeze every last bit out of it.
Regards
classd4sure said:Hi,
What do you plan on doing about that, turning it up, or just trusting that a 10% surge is a rare occurance? A TVS might be enough, would be cool to squeeze every last bit out of it.
Regards
Use a regulated power supply if you want to squeeze out the last few possible watts without going in protection all the time when the line voltage is a bit higher and when transformer regulation factor is an issue.
I plan to try a regulated switching power supply, not for the above reason however. I don`t care about those last few watts, I don`t think you can hear that 1 dB difference or so. Of course the power supply voltage should be as solid aspossible but I don`t think there is any need to make sure that you get the highest possible power supply voltage.
Gertjan
Firstly, I will be using a 1000VA toroidal transformer, so regulation will already be quite tight. I am also relying on the fact that excursions to +10% will be a rare occurrence. As I mentioned earlier, I will be running either a pair of very power hungry subs or using the amp to pound out tunes in a pub back room or parties, so there will always be an amount of loading anyway.
I think a regulated PSU is a waste of time as it will not allow you to get the most out of your power supply and is something else to go wrong and create heat, EMI etc.
I just like to think that I can squeeze all that is possible out of the UcD400 🙂 This may not be the ideal for everybody.
I think a regulated PSU is a waste of time as it will not allow you to get the most out of your power supply and is something else to go wrong and create heat, EMI etc.
I just like to think that I can squeeze all that is possible out of the UcD400 🙂 This may not be the ideal for everybody.
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