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Ok...tired subject, but I need advice.
- Thread starter dukey donkey
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- advice need advice
Indeed. Viva los carrots.
Unfortunately, making one's self happy can have drawbacks...
- Feb 12, 2006
- 61,060
- 5
- 221,081
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
You are supposed to smoke it, not make a salad out of it
I like it in butter, on a grilled cheese.
God's gift is pretty darn versatile....lolYou are supposed to smoke it, not make a salad out of it
Always good when things happen by chance that make my day..lol serendipitous...
In case anyone cares... this is my current eq situation lol
yeah the voice is up a little but I like how it makes my lows sound... The Delta 12lfa's roll off the highs and high mids pretty early...have a bit of woolly texture I have to tweak out, but at current settings I get crispy attack and deep, thick bass... good mid presence too... Gonna play with the full band tonight and see for sure but I have a good feeling they're going to ask me to turn down lol
I looked over this thread somewhat out of curiosity. A couple questions...
The places you play do not reinforce the bass?
I cannot understand why anyone would not.
Get yourself a reasonable active DI, and keep it with your rig. Use it between the bass and the amp. This way, the room can hear what your bass sounds like. The bass rig on stage, is for you, and the bandmate's benefit of hearing you on stage. Not for the room. And there is some point where the dynamic volume level on stage is just too much. No need to have 125 dB stage levels. No matter what the style of music is. This competes with the Sound System, in a bad way too.
I have been in Pro Audio, and a performer, (over 50 years- over 10,000 shows) and always DI the bass like this. I also do amp and equipment repairs, and find in most cases, the DI built into the back of amplifiers, is placed as more of a convenience to the Engineering, rather than one that is transparent, with regards to the best place in the circuit to put it. I never use them... In the circumstance of a lower dynamically loud band, and an exceptional Bass rig, I will add a good low end mic, (like an RE 20) in front of the cabinet in a second channel.
I am also curious as to what design was used in making your speaker cabinets?
You really cannot just make some box, and put random speakers in there, and have it work right. You pick the speakers you want to use, and design the cabinet to the T/S parameters of the speakers. A wrong cabinet volume/space, a wrong port size, if anything is off, you will have limited bandwidth, and limited volume.
The places you play do not reinforce the bass?
I cannot understand why anyone would not.
Get yourself a reasonable active DI, and keep it with your rig. Use it between the bass and the amp. This way, the room can hear what your bass sounds like. The bass rig on stage, is for you, and the bandmate's benefit of hearing you on stage. Not for the room. And there is some point where the dynamic volume level on stage is just too much. No need to have 125 dB stage levels. No matter what the style of music is. This competes with the Sound System, in a bad way too.
I have been in Pro Audio, and a performer, (over 50 years- over 10,000 shows) and always DI the bass like this. I also do amp and equipment repairs, and find in most cases, the DI built into the back of amplifiers, is placed as more of a convenience to the Engineering, rather than one that is transparent, with regards to the best place in the circuit to put it. I never use them... In the circumstance of a lower dynamically loud band, and an exceptional Bass rig, I will add a good low end mic, (like an RE 20) in front of the cabinet in a second channel.
I am also curious as to what design was used in making your speaker cabinets?
You really cannot just make some box, and put random speakers in there, and have it work right. You pick the speakers you want to use, and design the cabinet to the T/S parameters of the speakers. A wrong cabinet volume/space, a wrong port size, if anything is off, you will have limited bandwidth, and limited volume.
If you rewire your 4x12 back to 8Ω, that would give you the option of using 2x12, 4x12, or 6x12 depending on the gig and how much you want to carry. You will have to turn up the master volume to get the same power to the cab(s) at higher ohms. This is normal and will not hurt your head or speakers.
It's possible that you were having problems using both cabs because they were out of phase with one another. This is easy to check with either a 9v battery or a multimeter. If the cabs are out of phase, you will have a significant drop in volume, especially in lower frequencies.
- Feb 12, 2006
- 61,060
- 5
- 221,081
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Audiodude57... your comments about DIs on amps in general is pretty inaccurate. Many DIs (when set to pre) are placed in exactly the same place a source where an active DI would be placed, the active part being handled by the input buffer which is the same as the active input circuit of the DI. This is certainly true of every DI I have designed into maybe 25 models of bass amp that I have been responsible for in my career.
I am also a (semi-retired) touring pro audio guy for at least as long... I might know a thing or two about DIs.
I am also a (semi-retired) touring pro audio guy for at least as long... I might know a thing or two about DIs.
Audiodude57... your comments about DIs on amps in general is pretty inaccurate. Many DIs (when set to pre) are placed in exactly the same place a source where an active DI would be placed, the active part being handled by the input buffer which is the same as the active input circuit of the DI. This is certainly true of every DI I have designed into maybe 25 models of bass amp that I have been responsible for in my career.
I am also a (semi-retired) touring pro audio guy for at least as long... I might know a thing or two about DIs.
Maybe your amp is different than I have worked with, in the shop and in real world application.
I prefer to DI the bass directly out of the instrument, and not after a buffer/1st gain stage in any amp. My preference, and get great bass tones to FOH, with the exception of a POS bass. Most guys have good-great instruments. Nothing right or wrong about my approach. It works for me, to hear the instrument, uncolored by anything in between.
- Feb 12, 2006
- 61,060
- 5
- 221,081
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
The input buffer of many amps is "exactly" the same thing as the input stage of an active DI (which I have designed a few as well).
There is no difference, you may think there is but not on many amps. This is just another old wives tale based on some fact 30+ years ago, as well as on some poorly implemented amps, but this is a far cry from the generality you stated earlier.
There is no difference, you may think there is but not on many amps. This is just another old wives tale based on some fact 30+ years ago, as well as on some poorly implemented amps, but this is a far cry from the generality you stated earlier.
So you've never worked on a real world Mesa Boogie bass amp? (or GenzBenz?) Because Agedhorse designs them, including the exact amp this thread is about, D800+. I'm inclined to believe him.
Only MB guitar amps...never had a need to repair a bass amp from them... so they are well designed. But I have schematics for about everything out there. And I stand at my preference, of DI'ing...
- Feb 12, 2006
- 61,060
- 5
- 221,081
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
YOUR preference is one thing, but your initial statement about "most bass amps" was not factually accurate.
With the OP's amp, it is (by design) identical to an active DI right at the output of the bass... except better because the 1M typical input impedance of the active DI doesn't combine with the input impedance of the amp to pull the load down to 500k. In this respect, having the DI be part of the amp is "better".
With the OP's amp, it is (by design) identical to an active DI right at the output of the bass... except better because the 1M typical input impedance of the active DI doesn't combine with the input impedance of the amp to pull the load down to 500k. In this respect, having the DI be part of the amp is "better".
After 175 posts the solution still evades. How about this suggestion ?
Your quad box drivers are each 8 Ohms
4 x 8 in series/parallel = 8 Ohms
4 x 8 in parallel = 2 Ohms
Your twin box drivers are each 4 Ohms
2 x 4 in parallel = 2 Ohms
2 x 4 in series = 8 Ohms
No matter which way you wire the cabinets (series/parallel) or the speakers in them (series/parallel) you will not be able to achieve a state where the power is shared equally between the drivers
The lowest cost solution is to replace the 4 Ohm drivers with 8 Ohm units and connect in series = 16 Ohms effective.
To ensure the sound does not change it is advisable to stay with the Eminence units for the second cab.
Then wire the 4 x 8 cab drivers in two separate pairs of series connected (do not join them in the middle) units = 2 x 16 Ohms in parallel = 8 Ohms effective
When you connect the second cab you will have three pairs of 16 Ohm circuits in parallel = 5.333 Ohms effective
This is close to an ideal load for amps rated 4 Ohms minimum load
You now have one 8 Ohm quad cabinet and one 16 Ohm cabinet
The driver specs show the two different models as having similar SPL so the speakers should all sound about as loud as each other
But as I have previously mentioned, and always subject to the amplifier's ratings and stability, the lower the load on a solid state amp the better the low-end bass performance
You have proved this with your 2 Ohm cab test, which suggests the problem was load matching and not the DIY speaker cabs.
But make sure the amp will handle the lower load
Also when you consider the frequency response curves of your drivers there is considerable rolloff in the low-end range. This is normal but to offset it requires the bass tone control or EQ set to boost the low-end bass response to your personal preference. That requires more power from the amp and into the drivers in that LF range.
To obtain equivalent power (loudness) from a 5 Ohm load to what you are getting into a 2 Ohm load you will need a higher rated powered amp for the 5 Ohm load - more or less double
You are close to a solution
- Feb 12, 2006
- 61,060
- 5
- 221,081
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
That suggestion was made already, but at the time we could not pry the necessary information out of the OP.
A better solution is to ditch all that crap and simply buy a good used speaker cabinet that does what the OP needs right from the start, one that he can try before deciding. The path he has chosen will end up being more expensive for a crapshoot solution (assuming he doesn't damage an amp in the process).
A better solution is to ditch all that crap and simply buy a good used speaker cabinet that does what the OP needs right from the start, one that he can try before deciding. The path he has chosen will end up being more expensive for a crapshoot solution (assuming he doesn't damage an amp in the process).
