Did you ever developed a speaker from scratch?
It's not the LEVEL of the chassis, it's the frequency response which is not linear in 99% of the cases when built in the cabinet. Baffle step, edge difraction etc. add to the frequency response. Making an electronic perfect corssover will lead to a rally bad frequency response.
An older project - the fat lines are the raw speaker drivers. You need EQ AND FILTERS to get them linear. (and these are VERY well behaved drivers in a fitting cabinet)
It's not the LEVEL of the chassis, it's the frequency response which is not linear in 99% of the cases when built in the cabinet. Baffle step, edge difraction etc. add to the frequency response. Making an electronic perfect corssover will lead to a rally bad frequency response.
An older project - the fat lines are the raw speaker drivers. You need EQ AND FILTERS to get them linear. (and these are VERY well behaved drivers in a fitting cabinet)
I get that. I'll measure them, I'll add what's needed. The question was about choosing the right amp modules, I know that's not all!! But yes it's interesting to see what you started with and where you got in the end.
Seriously, what IamJF shares are textbook knowledge...at least for speaker design...
The reason why we said so much about this is because that's the principle to follow. Not that you use some soulution/CH precision/FM acoustic amps will help on this problem.
Certainly you can design the active analog circuit with EQ to flatten the response of each band as well.
If you don't have time to read the loudspeaker design cookbook (or similar material), perhaps you can consider reading some writing in DIYRM by Scott Hinson.
I spend money on Linkwitz-Riley analog crossover before with adjustable XO point, +- 6dB gain per band but not with delay.
It will output sound. But it's far from perfect. And I think people come here not just for making sound.
It's my experience that I think it's not worthy to to......but one might find it fun to play with.
The reason why we said so much about this is because that's the principle to follow. Not that you use some soulution/CH precision/FM acoustic amps will help on this problem.
Certainly you can design the active analog circuit with EQ to flatten the response of each band as well.
If you don't have time to read the loudspeaker design cookbook (or similar material), perhaps you can consider reading some writing in DIYRM by Scott Hinson.
I spend money on Linkwitz-Riley analog crossover before with adjustable XO point, +- 6dB gain per band but not with delay.
It will output sound. But it's far from perfect. And I think people come here not just for making sound.
It's my experience that I think it's not worthy to to......but one might find it fun to play with.
You all assume too much. I ask a question about one topic and that doesn't mean I ignore the rest.
"Not that you use some soulution/CH precision/FM acoustic amps will help on this problem." I know. I still need and want to build that amplifier though.
"DIYRM by Scott Hinson" that's a two way with a passive crossover, what does that have to do with my project? I might know your answer, all those principles discussed. I did read about those elsewhere, is sound-au.com a respectable source? I thought it was, but you never know..
I understand you all want to make sure I'm not just diving into a project knowing nothing. No worries. I just don't want to list the whole project or what I know and what I don't know. I've been reading a lot, had e-mail contact with SB Acoustics themselves, appointment with a speaker builder/sound engineer, it's all been taking care of.
But when it came to the amp I wanted to be open for suggestions on the modules, that's all. Not second guess everything which I did not spell out. But I did see loads of valuable tips.
It's just strange all those assumptions. Maybe it's something in the way I formulated the question which triggers it, maybe every conversation here goes like
this, I don't know.
"Not that you use some soulution/CH precision/FM acoustic amps will help on this problem." I know. I still need and want to build that amplifier though.
"DIYRM by Scott Hinson" that's a two way with a passive crossover, what does that have to do with my project? I might know your answer, all those principles discussed. I did read about those elsewhere, is sound-au.com a respectable source? I thought it was, but you never know..
I understand you all want to make sure I'm not just diving into a project knowing nothing. No worries. I just don't want to list the whole project or what I know and what I don't know. I've been reading a lot, had e-mail contact with SB Acoustics themselves, appointment with a speaker builder/sound engineer, it's all been taking care of.
But when it came to the amp I wanted to be open for suggestions on the modules, that's all. Not second guess everything which I did not spell out. But I did see loads of valuable tips.
It's just strange all those assumptions. Maybe it's something in the way I formulated the question which triggers it, maybe every conversation here goes like
this, I don't know.
Very well. I'll stop then, good luck.
"I understand you all want to make sure I'm not just diving into a project knowing nothing. No worries. I just don't want to list the whole project or what I know and what I don't know. I've been reading a lot, had e-mail contact with SB Acoustics themselves, appointment with a speaker builder/sound engineer, it's all been taking care of."
That would be very spectacle since what you choose for your analog active crossover are all LR based crossover and will guarantee you only the electrical response to match the desired response but not acoustically.
Indeed I shouldn't presume you don't know that's the acoustical response that matters but not electrically. Just the option you put tells me otherwise.
Anyway, good luck.
"I understand you all want to make sure I'm not just diving into a project knowing nothing. No worries. I just don't want to list the whole project or what I know and what I don't know. I've been reading a lot, had e-mail contact with SB Acoustics themselves, appointment with a speaker builder/sound engineer, it's all been taking care of."
That would be very spectacle since what you choose for your analog active crossover are all LR based crossover and will guarantee you only the electrical response to match the desired response but not acoustically.
Indeed I shouldn't presume you don't know that's the acoustical response that matters but not electrically. Just the option you put tells me otherwise.
Anyway, good luck.
"Indeed I shouldn't presume you don't know that's the acoustical response that matters but not electrically" — That's by far the most annoying sentence I read on this forum. You say you'll stop and then go on.
It's not that you information isn't valuable. It's your presentation of it which is ultra wise *** without really explaining anything on-topic.
It's not that you information isn't valuable. It's your presentation of it which is ultra wise *** without really explaining anything on-topic.
A quick note on sound-au.com Rod is a skeptic and won’t take any BS. Information he publishes is fact checked to his satisfaction before he publishes. However some of the articles are now a little dated and in some cases the state of the art has moved on a little since articles were written, but in most cases the info is good. Since there is only on person creating content the site is absolutely remarkable. All of Rod’s project boards worked well for me first time and for me that is worth a lot.
I hope you get as much musical enjoyment out of your projects as I have from mine!
I hope you get as much musical enjoyment out of your projects as I have from mine!
We want to help people in their decisions. That's normally the reason they ask here.
You obsess about a more or less non-topic (match wattage of amp to drivers) and refuse the tipps you got. People tell you that you need EQ to correct the driver and fit the crossover slopes to the driver behaviour and next post you tell us you use an all 4th order electronic crossover.
So - much fun with the project!
Thanks for sharing - that's interestingly affordable for a couple of side-projects that I have in mind.
My main speakers are 3 way and are controlled by a MiniDSP Eight, which is great, but too expensive for me for projects.
Project 1/ I have DCM Timeframe TF700 speakers from which I am considering removing crossovers (that are now 40 years old), adding an active crossover, and triamping. Then placing the speaker cloth with a modern funky fabric, etc.
Project 2/ Buy Sansui SF-2 omni directional speakers (now 50 years old), strip the brown lacquer to replace with polyurethane; replace the drivers with modern neodymium units; supplement with a discrete subwoofer, e.g. SVS SB2000; create active 2-way + sub crossover; bi-amp them.
Until now, the cost of two more MiniDSP Eights was a hurdle, so this is very helpful.
Wasn't the next post. I started with that, it was in the original question from the start, that was always the plan, an amp for an active crossover. You can change the slopes on those boards!! I switched the source/brand of the boards when I found one which I think fits me better with somebody who answers the phone for questions.
I do or did not refuse the tips I get. Some of them were offtopic for me, schooling me on passive crossovers while I explicitly told that an active crossover was the setup for the project, some of them were very useful, lot of the info I already knew.
Doesn't matter the conflict is in the tone, internet is weird like that.
And that the wattage of an amp isn't important is a good thing to know. But you also can't just throw any driver combination or amp together, so I still think it's a valid question. Although you disagree.
The crossover guy advice me to work with an old A/B Rotel amp, and maybe update that one a bit. Like the RMB-1048. So I'm looking into that. But maybe you really want me to talk about slopes and EQ and not about amps. (I checked, it really is the amplifier sub forum)
Again, I'm not refusing the info, I will measure the drivers and will do what's needed to eq them, set the timing right, attenuation etc, but also again, I still need that multi channel amp, so checking my options.
About assumptions. No it's not you. It's just Diyaudio. It's a great place in soo many ways, but sticking to the topic is not our force. Rotels are good. Those are 4 channels? You only need ample headroom power for midletone. Much less power for highs and best a **** load of power beyond the rated power of rdrivers for bass. That is based on the efficiency of the divers youve chosen, but it's the same for most 3 ways. And only if you sometimes want to play loud. If volume is moderate you dont need much headroom if any. Going with identical amps can also have its benefits. Sometimes it's easier that their gainlevel is the same. Please report on progress and ask more questions. You will sometimes get some goldnuggets. Sometimes even what you ask for.
Cheers!
Cheers!
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DSP is a form of active crossover, so those suggestions are valid. They are suggested, because they are good. They are so good that many people don't bother with anything else anymore.
If you use analog active crossover, how did you plan to EQ? If you do it with the active crossover, you are most likely going to need to solder small electronic components. Is that no problem?
The Rotel is 8 channels, and we will try to merge two for the bass. https://www.rotel.com/sites/default/files/product/manuals/RMB-1048-OM.pdf It also has attenuation hidden on the front panel, so we have that twice so that will be okay.
"If you use analog active crossover, how did you plan to EQ? If you do it with the active crossover, you are most likely going to need to solder small electronic components. Is that no problem?" yes that's not a problem, those boards have the option to add extra's: "Two plug-in function boards per output to add additional filter stages." — https://audio-products.nl/shop/lr24-3/
See my plan isn't that bad;-)
I understand dsp, and I also understand why it's appealing. I want to try active crossover and analoge path after the pre-amp first. If it's not end game I'll search for the octo 8 or topping 8 channel and try that. I see it as a challenge, by now I'm seriously curious what the limits are. And yes I'll probably buy that Dayton microphone system and see what EQ is needed and get that on a small board. If all goes well, I'll build a dsp system next so I can compare.
See my plan isn't that bad;-)
I understand dsp, and I also understand why it's appealing. I want to try active crossover and analoge path after the pre-amp first. If it's not end game I'll search for the octo 8 or topping 8 channel and try that. I see it as a challenge, by now I'm seriously curious what the limits are. And yes I'll probably buy that Dayton microphone system and see what EQ is needed and get that on a small board. If all goes well, I'll build a dsp system next so I can compare.
That's right. You would need a sound card (or an "interface" as in pro world) with two input channels soundcard. The first channel is for the mic and the second one is a loopback. The idea is to capture precise flight time of the audio and that helps with time align and crossover design (oops you locked your slopes). Many of us use VituixCAD for design. The links on top of that page will teach you many things about how to measure individual elements.
If you want to go that path that's totally fine and you will gain a lot of experience!
It's just - we did that already. I had a Rotel amp for many years as main amp. I know 2 active systems from colleagues which used Rotel power amps. That was 15 years ago. These are good amps, but no comparison to Hypex or other modern amplifiers. Non of the systems use them now in 2023.
My first big electronic project as youngster was a preamp with 4th order ative crossover for the subwoofer. Nearly 25years ago. That works for a sub - not so for a 3way, you need EQ to get the drivers flat first but you know that now ;-)
Get a microphone with correction curve, otherwise you don't know if you get a good one or one of the few which are >6dB off at high frequnecies. Here some data, they measured a lot of microphones:
https://www.hifi-selbstbau.de/index...ik/500-mikrofonkalibrierungen-eine-uebersicht
So after all - started with ChipAmps and Rotel, got ICE Power and Pascal modules, ended with hypex and Benchmark AHB2.
Started with self built active crossovers for subs, learned the art of passive crossover, done Sub/Sat and active with PA systems and arrived at modern DSP with S/N in the 115dB range for the whole system.
You can do this journey way faster as we did 🤓 but when thinking about the cost of amps and time for setup and tinkering around ... I still recommend a Hypex DSP plate amp, a good measurement mic + interface and some REW tutorials. Cause very likely you will end about there anyways 😉