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Post by Boomzilla on Oct 7, 2020 12:01:39 GMT -5
I've received a power amplifier for review. The amplifier was delivered with a technical specifications sheet & warranty card, but no owners manual. I've looked online, and can't find one there either. The hookup is ambiguous. My confusions include the following: The speaker outputs have switches for "Std." and "Bridge." On every stereo amplifier I've ever seen that offers a bridged mode, the intention is for speaker wires to be connected to the red terminals of BOTH the right and left channels (no black "ground connection" is used). But I don't know if this amp is wired that way or not. The "bridged" switch may (or may not) activate an internal switch that connects the "out of phase" channel to what is normally the "ground" (black) terminal for that channel. The output jack labeling would imply that such an internal switch DOES exist, and that in bridged mode, the + and - terminals for the bridged channel alone should be used. But since I don't know for sure, and since there's no owners manual to clarify, I"m reluctant to experiment lest I damage the amp. The inputs are similarly confusing. All channels have both RCA and XLR inputs. Only two of the channels, however, are marked as "bridge" inputs. So my questions are, can the non-bridged inputs use the XLR inputs (despite the fact that the circuitry for those channels is unbalanced only). Based on prior experience, I believe that the answer is "yes." Many amps offer XLR inputs that have unbalanced circuitry, and I suspect that this one is probably similar. My other input question is "can the bridged inputs (when used in bridged mode) use the unbalanced RCA inputs, or do they require balanced XLR inputs?" Again, I suspect that the answer is "yes." Other amplifiers with balanced circuitry (the XPA-1 amps from Emotiva, for example) will accept input on either their XLR or RCA jacks. But without guidance from the manufacturer, I'm reluctant to experiment. Ultimately, I don't want to damage the amplifier because I don't know what the manufacturer intends. I've asked the manufacturer for guidance, but have not yet received a reply. Any help would be appreciated. Boomzilla |
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klinemj
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Post by klinemj on Oct 7, 2020 12:38:39 GMT -5
I would not experiment either, but...if I were to guess...
If you want to run bridged, you move the swith to "Bridge" and an internal switch makes it so you connect 1 speaker to the "Bridge Output 1" speaker outs and another to the "Bridge Output 3" speaker outs...and internal wiring controlled by the switch handles everything to get the amps that would provide "output 2" to connect to "output 1" and "output 4" to "output 3". And, when doing this, you would use inputs 1 and 3 and could use either RCA or XLR inputs.
If you don't want to run bridged, it could be up to a 4 channel amp.
Again - all guesses except that last part about up to a 4 channel.
What amp is it?
Mark
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Post by Boomzilla on Oct 7, 2020 13:10:27 GMT -5
Starke Sound AD4.320
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DYohn
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Post by DYohn on Oct 7, 2020 13:54:33 GMT -5
Looks like an internally bridged 4-channel amplifier. If you flip the swatch to "bridge" mode only the highlighted set of binding posts will be active. I recommend if you try this to make sure the amp is powered off before you move the switch.
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klinemj
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Post by klinemj on Oct 7, 2020 15:05:23 GMT -5
Interesting to see what you think of it. It's very odd that what is shown as a "manual" on line is really a spec sheet. Quite odd.
Mark
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Post by gus4emo on Oct 7, 2020 21:22:58 GMT -5
I've received a power amplifier for review. The amplifier was delivered with a technical specifications sheet & warranty card, but no owners manual. I've looked online, and can't find one there either. The hookup is ambiguous. My confusions include the following: The speaker outputs have switches for "Std." and "Bridge." On every stereo amplifier I've ever seen that offers a bridged mode, the intention is for speaker wires to be connected to the red terminals of BOTH the right and left channels (no black "ground connection" is used). But I don't know if this amp is wired that way or not. The "bridged" switch may (or may not) activate an internal switch that connects the "out of phase" channel to what is normally the "ground" (black) terminal for that channel. The output jack labeling would imply that such an internal switch DOES exist, and that in bridged mode, the + and - terminals for the bridged channel alone should be used. But since I don't know for sure, and since there's no owners manual to clarify, I"m reluctant to experiment lest I damage the amp. The inputs are similarly confusing. All channels have both RCA and XLR inputs. Only two of the channels, however, are marked as "bridge" inputs. So my questions are, can the non-bridged inputs use the XLR inputs (despite the fact that the circuitry for those channels is unbalanced only). Based on prior experience, I believe that the answer is "yes." Many amps offer XLR inputs that have unbalanced circuitry, and I suspect that this one is probably similar. My other input question is "can the bridged inputs (when used in bridged mode) use the unbalanced RCA inputs, or do they require balanced XLR inputs?" Again, I suspect that the answer is "yes." Other amplifiers with balanced circuitry (the XPA-1 amps from Emotiva, for example) will accept input on either their XLR or RCA jacks. But without guidance from the manufacturer, I'm reluctant to experiment. Ultimately, I don't want to damage the amplifier because I don't know what the manufacturer intends. I've asked the manufacturer for guidance, but have not yet received a reply. Any help would be appreciated. Boomzilla As long as it was not made in Russia....lol... |
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Post by creimes on Oct 7, 2020 22:42:02 GMT -5
I just found this picture of Boom trying to wire up his new audio gear   |
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Post by Boomzilla on Oct 9, 2020 15:40:52 GMT -5
Starke Sound does have a user manual that answers all questions for their amp. Somehow, my box didn't get one, though. For the record, Mr. DYohn was correct on the hookup. Starke employs a bunch of internal switches to accommodate bridged hookups. |
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klinemj
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Post by klinemj on Oct 9, 2020 16:22:16 GMT -5
Hey - that's what I said, too...where's my credit? Did I get dinged for typing "swith" instead of "switch"? LOL!
Mark
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DYohn
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Post by DYohn on Oct 9, 2020 16:44:55 GMT -5
Starke Sound does have a user manual that answers all questions for their amp. Somehow, my box didn't get one, though. For the record, Mr. DYohn was correct on the hookup. Starke employs a bunch of internal switches to accommodate bridged hookups. In other words, "Exactly like many car audio amplifiers."  |
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Post by Boomzilla on Oct 9, 2020 18:21:03 GMT -5
Ah - I have ZERO knowledge of car audio...
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Post by Boomzilla on Oct 9, 2020 19:12:58 GMT -5
Hey - that's what I said, too...where's my credit? Did I get dinged for typing "swith" instead of "switch"? LOL! Mark You're right. Sorry. |
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klinemj
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Post by klinemj on Oct 9, 2020 20:12:33 GMT -5
LOL! No problem...just having fun!
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Post by vcautokid on Oct 10, 2020 3:20:19 GMT -5
Bridging is always about the outputs. And never never are the negatives ever used, otherwise the potential unhappiness occurs. The inputs don't really care. And yes, many Balanced inputs don't always stay that way going through summers or phase splitters and so on. Not the end of the world as you still get the benefit of common mode noise cancellation, and in some cases a bit more voltage to play around with. Bridging or the old term Strapping is always with the pluses tied together.
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KeithL
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Post by KeithL on Oct 10, 2020 12:33:20 GMT -5
I was just reading this - and the same thing occurred to me as vcautokid brought up...
What 405x5 is talking about is NOT "bridging"...
In its normal usage, in the context of audio equipment, "bridging" refers to a particular way of connecting two channels together. It refers to connecting two otherwise separate amplifier channels together as a single fully balanced channel... You feed a normal input signal to one channel... And an inverted signal to the other... (With unbalanced inputs this can be achieved using a separate inverter circuit or by re-configuring one of the amp channels to invert.) (With balanced inputs it can be achieved by exchanging the (+) and (-) input leads for one of the amp channels.)
The speaker is then connected between the (+) outputs of the two channels... (The grounds are connected together - which is assumed to be the case - since both are ground to begin with.) The result is a single fully differential fully balanced amplifier channel.
MOST amplifiers can be bridged... with the following considerations... - Since the speaker is connected between the "hot" outputs of both channels neither speaker wire can be grounded.
- Each amplifier channel will see 1/2 of the speaker's total load impedance. (If you connect an 8 Ohm speaker to a bridged amplifier each of the amplifier channels "sees" a 4 Ohm load.)
- SOME amplifiers which are not specifically designed to be bridged may become unstable if you bridge them. (This won't happen with most amplifiers. However, if it does happen, it could result in damage to the amp or the speaker.) - Every fully balanced amplifier is already bridged (so you cannot then bridge two of them together.
What 405x5 is describing is strapping the two SPEAKER outputs together - presumably in order to make more output current available. This is NOT what is normally meant by "bridging" and is NOT what the "bridging switch" on a normal amplifier is doing.
THIS MUST *ONLY* BE DONE WITH AMPLIFIERS THAT ARE SPECIFICALLY DESIGNED TO ALLOW IT. IF YOU CONNECT THE TWO SPEAKER OUTPUTS OF A NORMAL AMPLIFIER DIRECTLY TOGETHER... YOU WILL *PROBABLY* CAUSE SERIOUS DAMAGE TO THE AMPLIFIER, YOUR SPEAKER, OR BOTH.
In case it wasn't obvious, we're talking about amplifiers without output transformers, which are wired directly to the speakers. With tube amps, and the occasional solid state amp that has an output transformer, the rules are a bit different.
Bridging is always about the outputs. And never never are the negatives ever used, otherwise the potential unhappiness occurs. The inputs don't really care. And yes, many Balanced inputs don't always stay that way going through summers or phase splitters and so on. Not the end of the world as you still get the benefit of common mode noise cancellation, and in some cases a bit more voltage to play around with. Bridging or the old term Strapping is always with the pluses tied together. I once bought a pair of Carver 1.0t’s. This “first generation” pair had no external bridging switch that would convert that beast into a 1000 watt mono block. Rather than join the + with an adapter, we pulled the covers (brand new) and internally soldered the positives together with a one inch piece of speaker wire. Elegant and neat, they ran like that from 1988 until 2001 when I broke for Home theater. I “debridged” them before selling them off all those years later. The power was ridiculous.....I could never use even half without sending my voice coils out into the center of the room. Whoever bought those amps. essentially ended up with new amps. because they were simply loafing the entire time I had them. |
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Post by mgbpuff on Oct 11, 2020 8:34:39 GMT -5
All well and good (for most amps). But Carver, as usual, is sometimes very different than most amps. The M 1.0t was designed as a differential amp from the start. one amp channel was out of phase with the other. The original amp (which the 405x5 had) had no stereo/ mono switch but had diagrams on the back to set up. The 2nd gen had a switch, a connection diagram, but it was not necessary to jumper anything. The power output was increased by a factor of 4 in the mono mode.  This pic has one of each version. |
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Post by 405x5 on Oct 11, 2020 19:03:22 GMT -5
All well and good (for most amps). But Carver, as usual, is sometimes very different than most amps. The M 1.0t was designed as a differential amp from the start. one amp channel was out of phase with the other. The original amp (which the 405x5 had) had no stereo/ mono switch but had diagrams on the back to set up. The 2nd gen had a switch, a connection diagram, but it was not necessary to jumper anything. The power output was increased by a factor of 4 in the mono mode. View Attachment This pic has one of each version. Exactly! 43 years, I’ve been with B.C. and it’s been a fun time 1976 to 1987 Phase Linear 400. 1987 to 2001 1.0t version one bridged pair 2001 /present Sunfire Signature Grand Signature. Next??? Who the Hell knows !! |
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