I am looking at setting up a pair of amps to run as mono-blocks and online several sites have posited this as a solution: I want mono blocks just because I can.
Or just a properly functioning bridged amp with increased impedance handling and wattage with a mono output of the input?
Will this affect tube amps more than SS (and I am guessing the answer is yes to tubes no likey)?
So what is going to happen should I attempt this? Is my GFCI going to melt? Will my drivers fuse? Silence? Sparks?
Or just a properly functioning bridged amp with increased impedance handling and wattage with a mono output of the input?
Will this affect tube amps more than SS (and I am guessing the answer is yes to tubes no likey)?
if your amplifier is rated for 8ohms speakers then in bridged you MUST use 16ohms speaker or higher.
If your amplifier is rated for 4ohms speakers then in bridged you MUST use 8ohms speaker or higher.
If your amplifier is rated as stable, or safe, into 4r0 resistor, this probably means it can drive an 8ohms speaker.
4r0 (resistive load) DOES NOT mean it can drive a 4ohms speaker that is reactive as all speakers are.
The fact that you are asking these questions tells me your are not safe to be let loose on using any mains equipment beyond the manufacturer's recommendations.
If your amplifier is rated for 4ohms speakers then in bridged you MUST use 8ohms speaker or higher.
If your amplifier is rated as stable, or safe, into 4r0 resistor, this probably means it can drive an 8ohms speaker.
4r0 (resistive load) DOES NOT mean it can drive a 4ohms speaker that is reactive as all speakers are.
The fact that you are asking these questions tells me your are not safe to be let loose on using any mains equipment beyond the manufacturer's recommendations.
You'd need four mono-blocks for two speakers, i.e., stereo. There's another catch. Bridged operation requires that one amplifier be driven by an inverted signal. You'd need a way to do that. IMO you'd be better off with a pair of stereo amps designed for bridged operation like most Crown power amps or other commercial/pro/reinforcement/pa/guitar amps. You flip the stereo/bridged switch on the back, connect to one input, and the amp takes care of the rest. Because they designed it for bridge operation there's at least some probability that it will survive!
The fact that you penned such a reply tells me that you are not safe to be let loose in any instructional, training, or educational environment.
I have tried to kludge my valve amps and no joy, so they wont do it. No blue flames, just silence when attempting to run one channel from both ground taps. Don't know the circuit topology.
Another way is to run an RCA-Y-Splitter to split each single male to two and to bi-wire each side.
Each amp would receive two channels of identical signal, each channel of the amp would have an output, and both outputs would lead to one speaker/driver/listening channel. Maybe this could cause issues with each side seeing the same bridged load, but should not be an issue.
Y-splitter will not solve the problem. The signal, going to one of the bridged amplifiers, needs to be inverted (180 degrees phase shift). See here for the proper bridging adapter:
Bridging Adapter For Power Amplifiers
Andrew's comments are 100% valid.
Cheers,
Valery
P.S. Read about the bridging pitfalls carefully, right above the schematic in the article.
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Thanks for the circuit suggestion.
I am just now realising that this site is run by and for terminal degree'd engineers ONLY and that no other points of view are all allowed. It's not really a hobbiest site, is it? More like a ''seek approbation for your idea from the engineers'' site.
Andrew and you could have worded it this way:
""You are asking a lot of beginner questions that an Engineer would immediately not ask. When you work on circuits be careful - but you seem responsible and cautious, if not highly educated in circuit topology. Just use basic common sense and a few simple rules and you will be fine. Here is the link to basic safety practices as a revision. Begin with low-V DC when you experiment.""
THAT'S how you could phrase it.
I am just now realising that this site is run by and for terminal degree'd engineers ONLY and that no other points of view are all allowed. It's not really a hobbiest site, is it? More like a ''seek approbation for your idea from the engineers'' site.
Andrew and you could have worded it this way:
""You are asking a lot of beginner questions that an Engineer would immediately not ask. When you work on circuits be careful - but you seem responsible and cautious, if not highly educated in circuit topology. Just use basic common sense and a few simple rules and you will be fine. Here is the link to basic safety practices as a revision. Begin with low-V DC when you experiment.""
THAT'S how you could phrase it.
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Hi miragem3i,
My answer to the first sentebce is "No" 🙂
This is a great international community for everyone, regardless of knowledge, experience, etc. We try to help, but as most of us communicate in many threads, we normally put things right to the point.
Sorry if it looked "offensive" - believe me, nobody meant it.
If you have more questions, including the ones with regards to bridging, you are welcome - me or somebody else will try to help
Best regards,
Valery
My answer to the first sentebce is "No" 🙂
This is a great international community for everyone, regardless of knowledge, experience, etc. We try to help, but as most of us communicate in many threads, we normally put things right to the point.
Sorry if it looked "offensive" - believe me, nobody meant it.
If you have more questions, including the ones with regards to bridging, you are welcome - me or somebody else will try to help
Best regards,
Valery
You will probably need to use an op-amp or something similar for input summing, like many commercially designed amplifiers do.
Hi SonyFan, you're right, op-amp buffer is a good solution if there is a requirement to preserve a decent input impedance, otherwise (if the source is rather powerful) couple of resistors will be enough 😉
Cheers,
Valery
Another solution for getting the balanced signal you need to bridge your amps is a transformer such as Jensen Transformers Jensen JT-11P-1 Line Input Transformer Audio Hum & Noise Eliminators at Markertek.com A bit easier to incorporate than the active circuit posted earlier.
Miragem3i, try not to be so easily offended. This is a great community and we strive to keep our new member SAFE. Sometimes this safety advice may seem a little harsh, but the spirit is to protect you from your own inexperience and eagerness to try new things.
As AndrewT pointed out, bridging can get you more power, but your amp needs to be able to handle the added current of a load with an apparent impedance of half of what it measures. Not all amplifiers are capable of handling this extra current at high powers. I certainly understand the "monoblocks because I can", but be sure that your amplifiers can handle the current with your speakers so you don't end up with amps in the shop for repair.
Miragem3i, try not to be so easily offended. This is a great community and we strive to keep our new member SAFE. Sometimes this safety advice may seem a little harsh, but the spirit is to protect you from your own inexperience and eagerness to try new things.
As AndrewT pointed out, bridging can get you more power, but your amp needs to be able to handle the added current of a load with an apparent impedance of half of what it measures. Not all amplifiers are capable of handling this extra current at high powers. I certainly understand the "monoblocks because I can", but be sure that your amplifiers can handle the current with your speakers so you don't end up with amps in the shop for repair.
This old amp that came with a bridging module
http://www.diyaudio.com/forums/soli...-ga28f-construction-thread-3.html#post3967704
http://www.diyaudio.com/forums/soli...-ga28f-construction-thread-3.html#post3967704
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