Bi-Amp unmatched gain, does it matter

mpitogo

McIntosh MA-5200 29db gain for mid/high
Rotel RB-1590 27.5db gain low

no active x-over just MA pre-out to both

F1nut

Yes

gp4jesus

F1nut wrote: »

Yes

yup.

mpitogo wrote: »

McIntosh MA-5200 29db gain for mid/high
Rotel RB-1590 27.5db gain low

no active x-over just MA pre-out to both

passively XO’d?

mhardy6647

-- some "trim" will need to be provided either before, during or after the XO.

"During" will (should!) work fine if one uses a separate active XO, along the lines of something like this...




or something like this, perhaps if one has an aversion to "pro" gear:

mpitogo

Dang ok so maybe I’ll just give up on the bi-amp and just bi-wire the RB-1590 to LSiM 707s.

Sounds like anything to try and bi-amp with mismatched gear will just complicate the signal path.

http://www.marchandelec.com/electronic-crossovers.html

https://www.minidsp.com/products/minidsp-in-a-box/minidsp-2x4?lang=en&gclid=CjwKCAjwnLjVBRAdEiwAKSGPIzErfSCBTp4IWqlWx4vmttiYG0YeVmURz1bdJOSAVIuE1HllR82f0BoCKtMQAvD_BwE

mhardy6647

There's a lot to be said for doin' crossovers in the low power (small signal) domain rather than post-power amplifier (i.e., in or just ahead of the loudspeakers). Why spend watts just cookin' chokes, capacitors and (power) resistors, huh? Ever ask yourself that?

tonyb

Why bi-amp to begin with ? The lsim series is easy to drive, you don't need massive power. I might try just using the Mac on them.

mpitogo

The Mac is currently powering them. Want to try more power. I think @Joey_V tried the rb-1590 and it wasn’t bad, just not as good as his Classé.

Joey_V

You dont like the RB1590?

mpitogo

@Joey_V quite the contrary, I’m breaking them in and enjoying what I’m hearing so far. I was missing out on serious bass with the MA’s amp section. I’m hearing stuff I did not hear before with the same LSiM 707 but fed with some amp of authority. Mind you there is no eq on my pre and I’m listening to music I’m familiar with.

I’m quite shocked actually...I thought power didn’t matter at the volumes I listen to, normally between 40-45% at times 50% with classical on the MAs volume knob.

soundfreak1

If you are going to biamp, external xo is required if you really want the results biamping offers. Short cuts just (no external xo) won't do anything worth while. As far as pro gear goes the rane isn't bad for the price but if you can go to the "home audio" version's ( and they are not cheep) it is well worth it. When done correctly it can truly be amazing.just get one with "gain controls for outputs and balancing is easy.

mpitogo

Thanks, I tried it out without a line level xo or gain control. Results where not impressive. I was looking at this http://www.marchandelec.com/xm66-electronic-crossover.html or just giving up entirely and just run the RB-1590 alone.

soundfreak1

I have used the Rane 22b with decent results, however when I found the vintage nakamichi EC100/PS100 (you can stick a fork I'm my ....well) they turn up on flee bay every once in a while when they do grab one! Usually around a duce and as long as the freq. Control is in good shape everything else can be replaced and upgraded (caps and the like) for less than 150.00. Best bang for the buck I have found or even heard of. Simple precise, accurate and dead quiet.

gp4jesus

Consider the DBX Driverack PA. I admit making or modding cables w/XLRs on one end or the other is a bit of a hassle. But the all XO choices & options, 5-band full PEQ, 31 band GEQ, and time alignment more than make up for it.

mhardy6647

gp4jesus wrote: »

Consider the DBX Driverack PA. I admit making or modding cables w/XLRs on one end or the other is a bit of a hassle. But the all XO choices & options, 5-band full PEQ, 31 band GEQ, and time alignment more than make up for it.

One may buy 'hybrid' cables and/or adaptors. Easy-peasy, although 'standardization' of XLR connectors is a little hit or miss historically.

www.markertek.com is your friend

kharp1

I'm in the camp of its suited for professional gear with dedicated xo, but, better to stay away from in home use.

gp4jesus

I don’t get the point (or points) that either of you are attempting.

mhardy6647 wrote: »

One may buy 'hybrid' cables and/or adaptors. Easy-peasy, although 'standardization' of XLR* connectors is a little hit or miss historically.

you've had a bad experience*? But other than that you would consider the DBX or like XO?

kharp1 wrote: »

I'm in the camp of its suited for professional gear with dedicated xo, but, better to stay away from in home use.

so a dedicated XO for home use is a bad idea?

mhardy6647

gp4jesus wrote: »

I don’t get the point (or points) that either of you are attempting.

mhardy6647 wrote: »

One may buy 'hybrid' cables and/or adaptors. Easy-peasy, although 'standardization' of XLR* connectors is a little hit or miss historically.

you've had a bad experience*? But other than that you would consider the DBX or like XO?

kharp1 wrote: »

I'm in the camp of its suited for professional gear with dedicated xo, but, better to stay away from in home use.

so a dedicated XO for home use is a bad idea?

My point(s).
1. you can make or buy cables (or adaptor plugs) to interface home and pro equipment.
2. The standard wiring of the three conductors in XLR cables wasn't standardized until surprisingly recently.

http://www.clarkwire.com/pinoutxlrbalanced.htm



I would absolutely consider the dBx or even a Behringer active XO. There is nothing wrong with pro grade equipment like this (although the quality of the Behringer stuff is somewhat cheezy). Lots of folks who know what they are doing use an admixture of consumer and pro equipment -- depends on what one is trying to accomplish and knowing what one's getting oneself into.

The semi-vintage Electrovoice active crossovers (which are highly configurable albeit not without effort!) are highly sought after in some circles -- recent prices thereof reflect this, too, unfortunately.

Full disclosure: the standard "line level" signals for pro audio are slightly different than the consumer standard. Practically speaking, most equipment, IMO/IME can be interconnected without issues related to signal overload (most hardware has an input attenuator somewhere in the chain).



(if you look closely, you'll see some pro components mixed in with this state-of-the-art "domestic" hifi -- one of the best I've heard/experienced, in fact).

soundfreak1

I have used pro xo''s, have several friends that have used them with decent results, myself included. Having said that they just don't sound as good! They (xo's) are not built for " high quality" sound reproduction. IMHO too much stuff inside not related too or needed for separation of freq. " stuff for room equalization and delays and such" good for venue sound but not necessary (or needed ) imho for home use. If you want room eq''s , buy a good eq but you don't need it in your xo as it just more stuff to introduce noise and distortion. When it comes to xo''s simpler the better. I prefer the nak as it is "dead quiet" does what it is suppose to do and leaves everything else the hell alone, plus not much more money and can be upgraded and updated for less than a buck or so. I have heard multi thousand dollar modern units that weren't a major improvement at 10 times the price.

mhardy6647

I don't disagree with any of the above (FWIW), being a less is more kind of guy myself. The commercial XOs are chockablocks with IC opamps -- not exactly a recipe for the highest-fi, but they ain't junk (well -- many of them ain't junk) and there is something to be said for a bit of flexibility. No, we don't need limiters and compressors, but adjustable delay could be a useful tool, as could be variable XO slopes and frequencies for all passbands. Some of the active XOs offer such amenities. If nothing else, a flexible active XO could be a good modeling tool.

RTA and EQ (nowadays in the digital domain, so D/A and A/D neeed for analog sources) is fine -- but if one wants to biamp, one still needs some flavor of XO (active or passive).

Zero experience with the Nakamichi in question - I don't doubt that it works well but does it do what the OP needs -- i.e., does it permit the XO frequencies that the OP is gonna need?





Is the slope adjustable? Looks like not -- what is the slope? Looks like maybe 6 dB/octave and the same XO frequency for low and high pass.

Believe me -- I have nothing against first order (ahem - given that I am currently running all-first order, albeit passive XOs on the Frankenaltecs), but I don't know what the OP wants or needs in terms of XO topology. It could be just what the doctor ordered, though.

soundfreak1

I don't disagree with above. I'm fortunate in having speakers specifically designed to be biamped from the manufacturer and when the "biamp switch" is ingaged it goes to a "different "internal xo optimizing the slope the manufacturer preferred in there speakers so there's more to it than just the crossove.r start with speakers optimized for it by the manufacturer is a good start I have tried it with many different speakers and never got the results I have with my current pair.

txcoastal1

mhardy6647 wrote: »

Is the slope adjustable? Looks like not -- what is the slope? Looks like maybe 6 dB/octave and the same XO frequency for low and high pass.

Even the Marchand Electronics, are either based on a 24db/48db slope. building a xover network is based on design i.e. Marchand Electronics is based on the Linkwitz-Riley network

mhardy6647

Ahh, that explains things.
Some of us are more bottom up.

DSC_9780 (3) by Mark Hardy, on Flickr

DSC_9976 (3) by Mark Hardy, on Flickr

kharp1

gp4jesus wrote: »

I don’t get the point (or points) that either of you are attempting.

mhardy6647 wrote: »

One may buy 'hybrid' cables and/or adaptors. Easy-peasy, although 'standardization' of XLR* connectors is a little hit or miss historically.

you've had a bad experience*? But other than that you would consider the DBX or like XO?

kharp1 wrote: »

I'm in the camp of its suited for professional gear with dedicated xo, but, better to stay away from in home use.

so a dedicated XO for home use is a bad idea?

My speakers come with an XO. When I ran band sound we use DBX's mostly, but, I've never found pro gear to be suited well to higher end home gear. I don't feel the trouble of trying to bi, or tri, amp home audio speakers beneficial. Don't know many speaker builders designing their speakers that way.

mpitogo

Thanks for the tips but as @kharp1 mentioned I'll just skip the potential noise generating extra hops in the signal path.

I just went with a new PS Audio Stellar Gain Cell DAC and Analog Preamplifier to replace my Macintosh MA-5200. PS Audio was running a sweet trade-in deal on their website, $510 off and couldn't resist.

Now I'm in the market for a new Phono Pre... I'm thinking Schiit Mani

gp4jesus

My apologies to the OP for the thread hijack.

a BIG thanks for comprehensive, flame-free responses! Also Holy Guacamole on those pics!

When I switched to the DBX to handle LR tower processing duties, making full use of its Time Alignment feature I heard details from “Boston*” (and many others) that I’ve never heard before. A light touch of PEQ helps to further tame the infamous RTi A** series edgyness**.
* listened to thousands of times; on vinyl in 70s & 80s, CD thereafter.
** going active removed most

Check my sig and/or look for details in a new post in:

http://forum.polkaudio.com/discussion/168616/audio-pro-ace-bass-subwoofer-b1-35-75-shipped#latest

or PM me on “a sub in each corner.”

Thanks for your indulgence. Tony

mhardy6647

I can offer what I think is the best possible reason to biamp, with active or passive crossovers.

Horses for courses.


* Midrange and treble amplification by single-ended, direct-heated triode. 45, 2A3, or 300B depending on loudspeaker sensitivity.
* Bass amplification with a top quality solid state amplifier (Perhaps a Nelson Pass product)

I would do it myself - except that I am too lazy and too cheap.

gp4jesus

mhardy6647 wrote: »

I can offer what I think is the best possible reason to biamp, with active or passive crossovers.

forgive my narrow mind - for me active only

mhardy6647 wrote: »

Horses for courses.

??

mhardy6647 wrote: »

Midrange and treble amplification by single-ended, direct-heated triode. 45, 2A3, or 300B depending on loudspeaker sensitivity.

above 300hz...*

mhardy6647 wrote: »

Bass amplification with a top quality solid state amplifier (Perhaps a Nelson Pass product)

Satified w/my current choice but...

*I would do it myself now except that I am too busy.

Looking toward to retiring by the end of next year.

Please wait till pm to click on the link I posted above. House population is over double the norm till ~ 3 pm tomorrow.

PS: Mark love your sig especially the physics, LOL

mhardy6647

Horses for courses is a British expression that means (at least to my understanding) use the right tool for the job.

Here's what Gurgle says:

soundfreak1

"Water seeks it's own level"

mhardy6647

This darned thread has me looking at active crossovers on eBAY today...