That's Class A for you 😉 Just under 70C is probably about right. Currents are high, casing is small... they run hot. If you need more convincing then check the bias currents are correct by measuring the volt drop across the 0.68 and 0.47 ohm resistor network and calculate the current. Should be around 1.6A from memory for the ACA. That's nearly 40 watt dissipation per channel, 80 watt in total. HOT.
(70C although hot to us is just ticking over as far as the semiconductors go so no worries there)
(70C although hot to us is just ticking over as far as the semiconductors go so no worries there)
that is helpful info, will check the currents, thank you Mooly!
And does this mean I can put a couple hot dogs on the chassis and grill while listening?
And does this mean I can put a couple hot dogs on the chassis and grill while listening?
I have to admit, I have never checked the temperature on my ACAs with anything more than my hand. 🤣
[[ Zencutor II ran hottest]]
Dern if I had known that I would have gone for those instead of the wimpy ACA 😉
And believe it or not, I actually kept a damp cloth with fan blowing on it on top of my Musical Fidelity A1-2008 here in Vegas last summer (great sounding amp by the way).
That worked to keep the amp from burning up, but it was a pain having to keep drizzling water on the cloth to keep it damp while listening...
Dern if I had known that I would have gone for those instead of the wimpy ACA 😉
And believe it or not, I actually kept a damp cloth with fan blowing on it on top of my Musical Fidelity A1-2008 here in Vegas last summer (great sounding amp by the way).
That worked to keep the amp from burning up, but it was a pain having to keep drizzling water on the cloth to keep it damp while listening...
next Summer put it in bucket of oil
if that worked for HAMs in Yore, it should work now
if that worked for HAMs in Yore, it should work now
Don't you guys have AC over there?
Imagine... running the big Aleph 2 while the AC is running.
We Americans are foolish sometimes... the things we do to listen to good music in comfort while we keep the beer cold.
Imagine... running the big Aleph 2 while the AC is running.
We Americans are foolish sometimes... the things we do to listen to good music in comfort while we keep the beer cold.
The power in Vegas and Phoenix is cheap.
Here by the Coast... where it seldom gets above 90F, we pay 600 bucks a month to keep the house at 78F. We use about 1500 KwH per month in August-September. After the lifeline allocation, our cost is 48 cents per KwH. We have a very well insulated home, two brand new highest efficiency units, five zones, and if we tried to keep the house at 70F it'd cost us a knock on the door from the State Power Kontrol Gestapo....
I was joking about the big amps. August-September is time for the Class D amps and the Bose Acoustimass.
@Zen Mod HAM: Honda of America Manufacturing? Excellent outfit. My wife dealt with their supply chain.
Here by the Coast... where it seldom gets above 90F, we pay 600 bucks a month to keep the house at 78F. We use about 1500 KwH per month in August-September. After the lifeline allocation, our cost is 48 cents per KwH. We have a very well insulated home, two brand new highest efficiency units, five zones, and if we tried to keep the house at 70F it'd cost us a knock on the door from the State Power Kontrol Gestapo....
I was joking about the big amps. August-September is time for the Class D amps and the Bose Acoustimass.
@Zen Mod HAM: Honda of America Manufacturing? Excellent outfit. My wife dealt with their supply chain.
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I am using Amp Camp Amps with XLR connections as a stereo mono block setup.
1)
How to connect a single REL's three wire sub speaker cable (with Neutrik Speakon) to the mono blocks (one sub for both channels)?
2)
How to connect two REL's three wire sub speaker cable (with Neutrik Speakon) to the mono blocks (one sub for each channel / mono block)?
Old REL instruction says: "We do not recommend connecting a single REL to mono blocks High Level because it could damage your REL or mono block amplifiers" and "For a single REL with mono blocks, we recommend connecting Low Level".
Should I just find a sub with "High Level Inputs and High Level Outputs" or with "XLR inputs and XLR output", like Genelecs (to cut lows away even before mono blocks and to get 100% working connections)?
I am looking for a REL model T/5X, as it is kind of base model.
1)
How to connect a single REL's three wire sub speaker cable (with Neutrik Speakon) to the mono blocks (one sub for both channels)?
2)
How to connect two REL's three wire sub speaker cable (with Neutrik Speakon) to the mono blocks (one sub for each channel / mono block)?
Old REL instruction says: "We do not recommend connecting a single REL to mono blocks High Level because it could damage your REL or mono block amplifiers" and "For a single REL with mono blocks, we recommend connecting Low Level".
Should I just find a sub with "High Level Inputs and High Level Outputs" or with "XLR inputs and XLR output", like Genelecs (to cut lows away even before mono blocks and to get 100% working connections)?
I am looking for a REL model T/5X, as it is kind of base model.
Hey OnionRing!
Which REL model(s) do you have?
Which preamp are you using?
I do not have an REL sub, so am googling and guessing a bit here... Neutrik Speakon connectors are 2, 4, or 8 pole (connections) so I doubt REL is somehow using only 3 of the connections. If you have an actual example (of a 3-connection Speakon) I'd enjoy seeing exactly what they are doing, though. They could be using a common ground.
Personally, I'd start by giving REL a call or email and telling them exactly what your plans are. They may even have a pre-made cable that you can purchase which will work exactly as you need. Outside of a few bad apples, I've always obtained good information from the manufacturer themselves.
If it were me, I'd start by simply running RCA cables to the sub directly from the preamp. Yes, the REL manual states that it is somehow gauche to do so...
"...LOW LEVEL INPUT: This single channel phono input allows for conventional connection to a preamplifier and should be used in the rare event that a HIGH LEVEL connection proves incompatible." It would be the easiest and likely safest way to start, and frankly is very much in the spirit of DIY audio. A little careful experimentation will teach you many lessons.
Which REL model(s) do you have?
Which preamp are you using?
I do not have an REL sub, so am googling and guessing a bit here... Neutrik Speakon connectors are 2, 4, or 8 pole (connections) so I doubt REL is somehow using only 3 of the connections. If you have an actual example (of a 3-connection Speakon) I'd enjoy seeing exactly what they are doing, though. They could be using a common ground.
Personally, I'd start by giving REL a call or email and telling them exactly what your plans are. They may even have a pre-made cable that you can purchase which will work exactly as you need. Outside of a few bad apples, I've always obtained good information from the manufacturer themselves.
If it were me, I'd start by simply running RCA cables to the sub directly from the preamp. Yes, the REL manual states that it is somehow gauche to do so...
"...LOW LEVEL INPUT: This single channel phono input allows for conventional connection to a preamplifier and should be used in the rare event that a HIGH LEVEL connection proves incompatible." It would be the easiest and likely safest way to start, and frankly is very much in the spirit of DIY audio. A little careful experimentation will teach you many lessons.
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bhjazz,
I don't have subwoofer yet, but I am looking for a base model, T/5X.
I want to use XLR only (as much as possible), so preamp's RCAs' are a little bit out of the question. This is a good idea, thought.
I know this might be a tricky connection, so my backup is Genelec 7050C in same price range as mentioned REL.
REL's three wire sub speaker cable should give you a link for that connection.
I don't have subwoofer yet, but I am looking for a base model, T/5X.
I want to use XLR only (as much as possible), so preamp's RCAs' are a little bit out of the question. This is a good idea, thought.
I know this might be a tricky connection, so my backup is Genelec 7050C in same price range as mentioned REL.
REL's three wire sub speaker cable should give you a link for that connection.
@OnionRing
I re-read your post and now see you don't actually have that sub yet. My mistake. And XLR is a fine choice. I use it myself!
Thanks for the link to an REL 3-wire cable. They are doing what I suspected: positive left, positive right, and one ground connection. Now we can go back to your original questions.
The REL T5/x does not have any XLR input so you're left with either the Speakon or RCA.
I find this comment concerning, however:
Gosh, the Speakon is high level only. Hmm.
If you decide to try...
First, take a look at this pic from the build guide at: https://guides.diyaudio.com/Guide/Amp+Camp+Amp+V1.8+Change+Information/10?lang=en Later on you can find step 15 MONO XLR Bridged from that post.
1) This will put the subs in mono (the signal is summed):
Since you would be using two ACAs running balanced mono bridged:
connect one positive (+) REL cable end to one of the red connections,
the other positive (+) red cable to the other connection,
and the last one (-) to the bottom black cable on the far left.
2) This will put the subs in mono for each channel (the signal is not summed):
connect one positive (+) REL cable end to one amp red connection (as per the pic above),
the other positive (+) red cable to <nothing>,
and the last one (-) to the same amp black cable connection on the far left.
The subs, then, end up being one channel or the other.
Finally, I don't know what these connections will do to the ACAs, how they would change the output impedance or anything, really. I will reiterate this information from my earlier post: give REL or an authorized REL dealer a call. They can confirm (or deny) my proposed connection methods and can better describe the impact these connections will have on your ACAs. I'd hate for you to release the magic smoke...or worse.
Cheers!
I re-read your post and now see you don't actually have that sub yet. My mistake. And XLR is a fine choice. I use it myself!
Thanks for the link to an REL 3-wire cable. They are doing what I suspected: positive left, positive right, and one ground connection. Now we can go back to your original questions.
The REL T5/x does not have any XLR input so you're left with either the Speakon or RCA.
I find this comment concerning, however:
Gosh, the Speakon is high level only. Hmm.
If you decide to try...
First, take a look at this pic from the build guide at: https://guides.diyaudio.com/Guide/Amp+Camp+Amp+V1.8+Change+Information/10?lang=en Later on you can find step 15 MONO XLR Bridged from that post.
1) This will put the subs in mono (the signal is summed):
Since you would be using two ACAs running balanced mono bridged:
connect one positive (+) REL cable end to one of the red connections,
the other positive (+) red cable to the other connection,
and the last one (-) to the bottom black cable on the far left.
2) This will put the subs in mono for each channel (the signal is not summed):
connect one positive (+) REL cable end to one amp red connection (as per the pic above),
the other positive (+) red cable to <nothing>,
and the last one (-) to the same amp black cable connection on the far left.
The subs, then, end up being one channel or the other.
Finally, I don't know what these connections will do to the ACAs, how they would change the output impedance or anything, really. I will reiterate this information from my earlier post: give REL or an authorized REL dealer a call. They can confirm (or deny) my proposed connection methods and can better describe the impact these connections will have on your ACAs. I'd hate for you to release the magic smoke...or worse.
Cheers!
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