Ed-
Glad to see you got them. Please let me know if there were any issues.
All-
I sold 4 pairs of the heat sinks. I have two pair left. $25 for 1 pair, $40 for both + $15 shipping in the US.
I have priced shipping out of the US, and I think you'd be better off going with Conrad sinks due to the cost of shipping.
Glad to see you got them. Please let me know if there were any issues.
All-
I sold 4 pairs of the heat sinks. I have two pair left. $25 for 1 pair, $40 for both + $15 shipping in the US.
I have priced shipping out of the US, and I think you'd be better off going with Conrad sinks due to the cost of shipping.
rabstg said:Ed-
Glad to see you got them. Please let me know if there were any issues.
All-
I sold 4 pairs of the heat sinks. I have two pair left. $25 for 1 pair, $40 for both + $15 shipping in the US.
I have priced shipping out of the US, and I think you'd be better off going with Conrad sinks due to the cost of shipping.
You have mail,
I'll take all 4 units.
Paypal OK?
Blessings, Terry
Terry - you are STILL building amps? The power company will have to give you our own substation soon. 
Balanced input on KSA?
Hi
Anybody tried to "upgrade" the KSA-50/100 to balanced-XLR-inputs ?
Im interested to try this "improvement" on my KSA-project.
If yes, is it possible for you to post a schematic for such a solution?
Regards 😎
Hi
Anybody tried to "upgrade" the KSA-50/100 to balanced-XLR-inputs ?
Im interested to try this "improvement" on my KSA-project.
If yes, is it possible for you to post a schematic for such a solution?
Regards 😎
Hi,
stick a discrete opamp on the front end. Look at Borbely and Bryson and many others.
Read Jung first to see the importance of balanced source resistance/reactance (0.01% if you can achieve it) and high input impedance for excellent CMRR.
stick a discrete opamp on the front end. Look at Borbely and Bryson and many others.
Read Jung first to see the importance of balanced source resistance/reactance (0.01% if you can achieve it) and high input impedance for excellent CMRR.
Analog Devices makes a chip that converts single ended to balanced and balanced back to sigle ended. The SSM-2141/2142/2143 series.
Have not tried this yet, but looks interesting.
They sell for about $25.00 each.
Search for ssm 2142 on the opening page here:
http://www.analog.com/
Have not tried this yet, but looks interesting.
They sell for about $25.00 each.
Search for ssm 2142 on the opening page here:
http://www.analog.com/
You can convert a RCA signal to a XLR signal in two other ways:
1) Use a transformer to generate the -S signal. This is the preferred way since it gives you a true XLR balanced signal.
2) Simply tie one of the hot XLR conductors to ground. Of course, doing it this way you don't get the noise-reduction benefit of the balanced signal principle.
By doing method 2 you do not convert an RCA to an XLR signal (there is no such thing as an XLR signal - all that does is designate a connector type). What you will do is take a balanced signal and convert it to single-ended, thereby losing all the advantages of having balanced in the first place.
However equipment that accepts a balanced signal can be made to accept an unbalanced signal using method 2.
Balancing is only really of merit where: signal levels are low, the environment is electrically noisy, cable runs are long.
Since in an ordinary domestic environment none of these are really
applicable to a pre-power link, is it worth the bother.
1) Use a transformer to generate the -S signal. This is the preferred way since it gives you a true XLR balanced signal.
2) Simply tie one of the hot XLR conductors to ground. Of course, doing it this way you don't get the noise-reduction benefit of the balanced signal principle.
By doing method 2 you do not convert an RCA to an XLR signal (there is no such thing as an XLR signal - all that does is designate a connector type). What you will do is take a balanced signal and convert it to single-ended, thereby losing all the advantages of having balanced in the first place.
However equipment that accepts a balanced signal can be made to accept an unbalanced signal using method 2.
Balancing is only really of merit where: signal levels are low, the environment is electrically noisy, cable runs are long.
Since in an ordinary domestic environment none of these are really
applicable to a pre-power link, is it worth the bother.
Thanks for the tips
acenovelty:
Actually for 4-5 month ago I bought the Analog Devices chip set SSM-2141/2142 for an old Carver upgrading project and for balanced outputs. Also I can certainly use the chips for balanced input on a KSA-50 clone. Only drawback to this is I had to add more electronics in the signal pathways and this is not fun. Regarding the pricing, the chips is not that expensive as that, "only" 10 bucks each.
But on the other hand this solution gives me the opportunity to connect two amps in a bridge configuration and this will give more cancellation to distortion and noise with the benefit to raise the total output power with a factor of 4 (if big enough power supply and heatsinking/power devices), hm..........
Was only thinking of one thing: a solution like an OP-amp: with the two inputs inv. and non inv. Could this be a way to go. Shall try to draw a simple schematic for the discussion here later.
Any new tips are welcomed
Ragards 😎
acenovelty:
Actually for 4-5 month ago I bought the Analog Devices chip set SSM-2141/2142 for an old Carver upgrading project and for balanced outputs. Also I can certainly use the chips for balanced input on a KSA-50 clone. Only drawback to this is I had to add more electronics in the signal pathways and this is not fun. Regarding the pricing, the chips is not that expensive as that, "only" 10 bucks each.
But on the other hand this solution gives me the opportunity to connect two amps in a bridge configuration and this will give more cancellation to distortion and noise with the benefit to raise the total output power with a factor of 4 (if big enough power supply and heatsinking/power devices), hm..........
Was only thinking of one thing: a solution like an OP-amp: with the two inputs inv. and non inv. Could this be a way to go. Shall try to draw a simple schematic for the discussion here later.
Any new tips are welcomed
Ragards 😎
BobEllis said:Terry - you are STILL building amps? The power company will have to give you our own substation soon.
Ha, I'll quit when you do. 😀
Blessings, Terry
Re: Balanced input on KSA?
Jensen, Cinemag, and Sowter all make 10K input transformers that should be fairly straightforward to use. I almost got around to trying a balanced input connecting to the inverting side of the input diff pair, but it never got beyond a beermat sketch. One day...
Flodstroem said:
Jensen, Cinemag, and Sowter all make 10K input transformers that should be fairly straightforward to use. I almost got around to trying a balanced input connecting to the inverting side of the input diff pair, but it never got beyond a beermat sketch. One day...
A simple, elegant and not so expensive solution is certainly of interest to many here. Transformers for the task take up valuable case real estate. IC's require a power supply usually below 18V complicating how to power them. Regulating 60 to 85 volts down that much or providing another power supply in an already crowded case is another problem. Still, it's a really good idea. The devil is always in the details.
Perhaps an external device between the amp and other devices is a way to go. Anyone wanting to connect their amp to say a Berhringer DCX2496 that takes only XLR connectors for tri-amping a line array will be most interested. Me too.
Perhaps an external device between the amp and other devices is a way to go. Anyone wanting to connect their amp to say a Berhringer DCX2496 that takes only XLR connectors for tri-amping a line array will be most interested. Me too.
Attachments
Inrush Limiting
I believe this was discussed a few times in much earlier posts, but is anyone using Inrush Current Limiting Thyristors such as Ametherm in their KSA50s? If so, what initial resistance and continuous current ratings would be appropriate.
I think I've settled in on 94000uf per channel for smoothing caps (2 times 47,000 per channel), and I'm concerned about the current draw on start-up.
I have a couple of different 'soft-start' kits...Hypex and also Rob Cheng's, but I was wondering if the thyristors would do the job.
I'm using passive cooling by the way, so I don't need fan control even though that is a feature of the Hypex unit.
Robert
I believe this was discussed a few times in much earlier posts, but is anyone using Inrush Current Limiting Thyristors such as Ametherm in their KSA50s? If so, what initial resistance and continuous current ratings would be appropriate.
I think I've settled in on 94000uf per channel for smoothing caps (2 times 47,000 per channel), and I'm concerned about the current draw on start-up.
I have a couple of different 'soft-start' kits...Hypex and also Rob Cheng's, but I was wondering if the thyristors would do the job.
I'm using passive cooling by the way, so I don't need fan control even though that is a feature of the Hypex unit.
Robert
Hi,
I assume you have a toroid powering your Klones.
EI transformers do not have as bad a switch on draw.
Thermistors and/or resisitors work well for a single switch on event.
If you have a poor mains supply that can brown out or worse drop out for a very few seconds then Thermistors do not provide the in-rush current protection required. They need a little time to cool down. A latching mains cut out solves this problem but adds complcation. Simpler is resistor droppers and bypass relay.
BTW I would fit a relay whether Thermistor or Resistor.
Your capacitance is not an issue. One would need to go much higher before this becomes a problem. The problem is in the toroid construction and the way the magnetic circuit (flux) builds up (or rather doesn't).
I assume you have a toroid powering your Klones.
EI transformers do not have as bad a switch on draw.
Thermistors and/or resisitors work well for a single switch on event.
If you have a poor mains supply that can brown out or worse drop out for a very few seconds then Thermistors do not provide the in-rush current protection required. They need a little time to cool down. A latching mains cut out solves this problem but adds complcation. Simpler is resistor droppers and bypass relay.
BTW I would fit a relay whether Thermistor or Resistor.
Your capacitance is not an issue. One would need to go much higher before this becomes a problem. The problem is in the toroid construction and the way the magnetic circuit (flux) builds up (or rather doesn't).
Fedex just nocked on the door and the kits are delivered, theres just one thing. No biggie at al thou.
I seem to have 12pc 4184-diodes and only 2pc of Zeners in 4kits.
So I just wanted to know if I can use those 1,3W in This datasheet. Page 2 product BZX85C/27. The retailer didn't have 1W but there shouldn't be a problem, right?
I seem to have 12pc 4184-diodes and only 2pc of Zeners in 4kits.
So I just wanted to know if I can use those 1,3W in This datasheet. Page 2 product BZX85C/27. The retailer didn't have 1W but there shouldn't be a problem, right?
I use a CL-60 in each channel's toroid primary to limit inrush. Aptionally you cold short the CL-60 a few seconds after turn on but the voltage frop is only a volt and a half in my case and I don't short them out. Nelson Pass uses them in his amps and he also leaves em in circuit and doesn't short them out. They cost less than 2 bucks each.
Mark
"I seem to have 12pc 4184-diodes and only 2pc of Zeners in 4kits."
The diodes were mixed from the supplier.
The ones supplied are 200ma and was "approved" by the group.
All-
I ran short of the MJE15032 and 15033 devices and none of the following shops have any. Mouser, Digi-Key, MCM and Parts express are all out of the 32's.
I need to order some today or tomorrow to get these last kits done.. Any suggestions?
The diodes were mixed from the supplier.
The ones supplied are 200ma and was "approved" by the group.
All-
I ran short of the MJE15032 and 15033 devices and none of the following shops have any. Mouser, Digi-Key, MCM and Parts express are all out of the 32's.
I need to order some today or tomorrow to get these last kits done.. Any suggestions?
MJE15034/35 should work fine. http://www.onsemi.com/pub/Collateral/MJE15034-D.PDF I hope that solves the availability issues.