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I recently came to own a pr of JBL 4430s. I tried to bi-amp with a Bel Canto Set 40 on HF and a Dynaco ST400 on LF, a modest BBE crossover and a First Sound Pre-amp. Could not get close to the passive x-overs and have decided to abandon bi-amp. The Set 40 sounds fantastic on HF but does not have the power to really handle the LF too. Any suggestions from experience on what I should put to these classics to preserve the sweet tube sound but also provide a beefy tight LF?
Paul 4430
Follow Ups:
I dont profess to know it all about these babies. Ive only had them about 2 years.
But been driving them with their passive Xovers in tact, using 60 watt (I use them in pentode rather than triode) mono blocks. Currently using NOS Valves VRD mono blocks, which are 6550 push pull, with 5AR4 rectifier, 12AU7 into 12AX7 preamp stage. The preamp is a Tubes4hifi tube preamp. Its model SP12 with some souped up tweaks. Its a dual 12AU7 per channel design.
For my tastes and room size (which isnt super large) these go VERY loud! You have to turn the volume up to painful levels to make it sound like the amps are being pushed too hard. And Im somewhat young and like to play loud at times and Im telling you, the 60 watts these amps deliver have more than enough power to make these speakers sing without strain.
I understand over the years many folks say they need 200+ watts of SS power to sound their best. I may never know. Personally Ive never felt Ive been missing anything. And so far Ive always been a tube guy since getting into high end audio. Just been drawn to the sound and havent felt Ive missed anything with the selection process Ive done.
Ive also driven these with a 15 watt EL84 amp. And they sound great at moderate to low levels. When wanting to jam loud it cant drive them. No surprise there. Really short of crazy hard to drive speakers, I think a 6550 PP amp would suit most peoples needs. Granted if your a VERY anal / detailed oriented listener, maybe 60 tube watts wont do it for you. Fine, totally understandable. But for the average person, Id guess it would be satisfying. Ive been so happy with these amps and these speakers.
About the 4430. I can EASILY see how these speakers might not be for everyone. They dont do super tweeter highs AT ALL. What a shock knowing their design :-). Fine by me. They have a "live" sound to me. You can tell your listening to a horn but its not offensive. Ive also owned JBL L300s and the sound didnt do it for me. They did allot well but that old school JBL conical horn just doesnt jive with me. Overall the 4430 do have a flat sound to them. But are far from boring. Yes their bass is very pronounced. However I dont find it bloated or overblown. Also their upper mid is ok considering its only a 15" and a horn. Sure they are not the last word in detail but what they do to most music wins me over. Id classify them as forgiving. Its a sound one either really likes or its just not for them.
Hope you love yours. I dont see them going down in value for a while. Their well deserved cult following will keep em alive for a bit more.
Keep us posted on your experience.
All the best
Dave
Hi Dave
I don't think I thanked you for the info on your setup with the VRD Monos. It is good to hear from someone who has the same speaker and a good bit of experience listening and trying alternate components. I think I am giving up on the bi-amp possibility with these. I just keep hearing people say they are super challenging to correctly involve an active crossover with and the results may not be an improvement. I am going to look into the VRDs.
Thanks again for your input - I appreciate it.
Paul
Paul 4430
If your really interested in one of the best push pull tube amps out there, these would really rank as such (Id guess).
Looking at your Bel Canto 40 watt SETs and the Dynaco SS amp, Id guess these would be a big upgrade, for these speakers. I think a high powered single ended amp might not do all too well with a speaker like this. This really was never made for SE use. And a mediocre (no offense) SS amp really wont do this speaker justice.
I can tell you the VRD amps deliever EVERYTHING in spades on these speakers. The bass is just amazing! I feel Im missing nothing. They have elegance, detail, power and force whenever its demanded of them. And even when I feel like playing ridiculously loud they seem to not run out of steam.
Now if you have some 15x25 or bigger room, maybe these will not be what you want, I really wouldnt know. But for a conventional sized room, they will get PLENTY loud for my tastes.
Also Im using a MHDT Havana DAC for my digital needs. A D/A I also recommend with the highest marks.
Heres Craig's web page for the amps. In the pic he still shows the old build with a PCB on the pre stage for the amps. That is no more. He has long went all point to point wired inside.
I ordered mine with all premium parts and the price for the pair was about $3200. I really dont think theres anything out there for that money that could best these. No regrets at all.
All the best
Dave
Dave
Thanks for your suggestions. The VRDs do seem like a lot of bang for the buck. And, that fact that you have very good things to say and we share the same speakers, that is a big +. I do have a larger room, but can't imagine that the VRD will not do everything I would like it to.
I will definitely put these on my short list.
Say, do you have your JBLs on any stands? I would like to put mine up about 10-15 inches. Am considering custom 3 or 4 leg stands from Sound Anchors.
I may have some question about your DAC as well if you don't mind.
Thanks
Paul
Paul 4430
Yeah I really cant think of anything the VRDs lack. They are some of the best 6550 PP amps made IMO. Their builder Craig, really doesnt mess around. He hates audiophile mysticism and refuses to spend money needlessly on snake oil. He is quite the 180 from allot of builders and sellers out there. You might be a little taken back when you talk with him, again not many like him in this industry. I love it personally.
My 4430s are currently on the floor. They have their 2" factory stand built into the base. I know many of these speakers were hung or put in soffits in the wall. Ive no doubt that getting them about 10" high might add to some air and spaciousness. Currently the room I have this rig in is rather small so Im not missing anything sound wise. And with the buttcheek horns the highs spread high and low in the room just fine. But having them raised would help clean the lower freq Im sure. Just dont have the time to mess with my rigs these days. Hope to soon.
You should google MHDT Havana for countless reviews and praises of the DAC. Id have to agree with all the positives written. I wanted a DAC that was mellow and NON edgy but didnt miss any detail. I got it. Ive used a few other NOS dacs and this one has been my favorite so far. I really cant find anything not to like. But yes feel free to ask away.
All the best
Dave
As a rule of thumb with valve amps you can get away with 6dB less headroom compared to ss amps due to their benign clipping behaviour.
You really need high power ss amps not because you need the power but because you really need the headroom.
As much as I personally like ss amps I'd never ever would want the hear one get close to clipping.
With that in mind a 50w valve amp would be equivalent to a 200w ss amp.
Provided current delivery is not an issue of course.
Also how the harmonic distortion is VERY different on tube vs SS. Tube is easier on the ears vs SS, so Ive heard.
On the notion of clipping, this is another reason I prefer tubes. I use allot of old, sensitive drivers and dread the idea of ruining a voice coil. I like the idea if Im jamming loud and am driving the amp into a level of clip/distortion I run less a risk of killing any drivers. Cant even tell you how many tweeters I smoked using 70s-80s SS receivers as a kid/teen. I learned early on about blowing drivers. Only once I became a audio nerd as a young adult did I fully understand why. Not too much power, too little :-)
Yeah different strokes for folks. Ive heard many SS systems that sounded breath taking. I just like the sound, glow, reliability Ive come to know from my tube gear. Plus, IMO, it cost less to get some of the best tube has to offer if you know where to shop.
Talk about current delivery. For a PP tube amp these seem about as good as it gets for 6550 PP build. Hand made, point to point wired. Large filter capacitance and choke PS. Around $3k new. Id probably have to spend around $5k+ to get equivalent SS sound. All generalities but Im happy with what I have.
Dave
The best ss amp I've heard bar none cost £2000 for 750w per channel into 8Ohm and it is perfectly stable into 2Ohm.
I've got three of its little brothers and, like you, I am very happy with what I've got. ;-)
Yes after reading your insightful post I did look up your system profile.
Yeah those MC2 amps have quite a cult following. I must admit I did not know of them before. They seem to have a UK base. Not sure how big a splash they made here in the states.
Sad to hear the manufacturer decided to end that series and go class D if I read correctly.
But I did a bit of googleing and found allot of positive reviews. Also looked at a few under the hood shots and was VERY impressed with the build.
Would love to hear em if I had the chance locally. Doubt that will happen however.
A nice bang for the buck find you have there. I feel the same of my VRDs.
All the best
Dave
Only their two largest E-series amps are class D, all the others use exactly the same audio circuitry as the MC-series.
What they lack is the rather sophisticated digital control which is only really interesting when you get close to clipping or they get a bit warmer than they should.
The MC750 and MC1250 appear to live on though as Quested AP800 and AP1300.
PS: The bang for the buck was even better as I bought mine s/h: £350 for the MC450, £300 for the MC750 and £100 for the T500. They would have cost about £4000 new in total.
May I ask... Youve taken an approach many do not. Using studio / pro amps to drive your gear. Note I didnt say most dont as there are allot here who do also.
What other amps did you try that did and or didnt do it for you?
I love reading about others experiences and what they found along the way. What brought them to where they are now.
I must admit, Ive only really tried well made tube gear in my rigs. All the SS amps Ive owned and tried really need rebuilds so I feel Ive never really heard SS done well in my own gear.
Im young enough yet so theres time for me to hear more gear. For now I feel quite happy.
Thanks much for sharing your thoughts.
Dave
OPther amps I tried but not necessarily owned are Pioneer, Yamaha (domestic and pro), Phase Linear, QUAD, SAE, Harrison, Bryston, Arcam (easily the worst of the lot), Revox (quite good), NAD etc.
Can't remember all the model numbers though.
I used to spend a lot of time in studios btw so I always was after amps that do not anything by themselves.
I also noticed that I like high damping factors (that's valves out of the window) and more than sufficient power.
One thing that got me interested in MC2 amps was the fact that Terry Clarke designed them.
In case you don't know Terry, he founded Klark Teknik with his brother and KT gear was always famous for being as clean as it got.
Later I found out that the other guy involved in MC2s design is Ian McCarthy who started a HiFi company called EAR with a bloke called Tim de Paravincini.
PS: I do love valve power for instrument amps. There is nothing better for some sweet, creamy distortion. The amp in my Leslie organ speaker is a valve job powered by a couple of 6550s. A thing of sublime beauty when pushed into the red.
Very interesting.
I have in my possession an Aragon 2004, Phase Linear 400 ver 2, McIntosh MC250, Carver 1.5, a few other odd balls.
Ive always wondered if any rebuilt would make for a good taste test of SS done well.
I dont know how Id like it being as conditioned to my current likes in tubes. Can a 50-100 watt SS sound amazing on allot of the vintage speakers I know and love.
Just seems like you and I have fallen for a different sound of amp. Im sure what Im used to hearing is probably different from your known sound and tastes.
If youve heard any of my amps and were impressed let me know. Not sure if I should have one rebuilt and drive these 4430s for a listen.
One thing I was also wondering about. You mention your being after totally neutral and non colored (or so Ive interpreted). But dont your amps have some kind of digital DSP type of addition to the amp? Thought you mentioned about them doing something to the signal when driven hard. Again I may be totally off in this perception. Sorry if so.
Thanks much to educating me on some of this stuff.
All the best
Dave
Friend of mine used to totally swear by his Phase Linear but when I saw him again a week after he heard my MC2 he had bought two of them already!
It is a popular misconception that the MC-series amps are digital or have DSP built in and I suspect that is the reason I got at least one them so cheap.
Thing is the amp is digitally controlled but there is nothing digital at all in the signal path.
What it means is that a little computer overlooks the workings of the amp ie if it gets close to clipping or overheating instead of limiters kicking in or relays tripping the computer fades down the supply rail voltage until the danger cedes. The amp will usually not go silent, just quieter.
It also works at switch on when the computer checks that everything works as designed and then fades the supply rail voltage up. This also increases the amps longevity as ss gear tends to fail on switch on in the vast majority of cases.
The audio path is as short as possible and essentially a standard class AB bipolar circuit.
However it is heavily biased (Ian McCarthy told me that the chances it will get into class B mode at home are small to nil) and the driver stage is current driven rather than usual voltage transfer design.
Hi DJK
Thank you for replying. I did bi-amp with a BBE Electronic crossover at 1K+/- but could never really find the right sound. Bass was always overpowering. I am not very knowledgeable in the physics of speakers and sound, so do not often understand the technical side and trouble shooting measures. The builder of my Pre-amp - Emanual Go of First Sound, encouraged me to keep the number of components to a minimum, and I have ready others saying that bi-amp of the 4430 is usually not going to bring a better result than the passives JBL put in. I am not happy with the Bel Canto alone however and do not believe I am able to come close to the dbs you are mentioning. I wonder if there is a problem with the Set 40 that I am unaware of? I could change out the pre-amp and see what happens with the Bel Canto? I bought the First Sound on pure reviews and blog writings. Never heard one.
Do you think I should return to a bi-amp? Any other thoughts?
THanks
Paul
Paul 4430
The treble on the 4430 needs a 6dB/oct boost from 3kHz upwards.
Some active xovers feature a cd horn correction which does just that although the frequency at which the boost starts may vary.
Thanks B.L.
Do you have any crossover suggestions that have this feature or might be a good fit for these speakers? Any help is appreciated.
Paul 4430
The only new ones I could find were the Behringer CX3400 and the Samson S3-way.
Both are rather cheap, the trick is to find out if one of them is cheap&cheerful rather than cheap&nasty.
Either that or go digital which would make things a lot easier.
I use s/h BBS FDS360 and a parametric eq for my Tannoy-based speakers since Tannoy DCs need the same cd horn correction and also a mild notch.
THanks B.L. I appreciate your suggestions. I will check them out.
Paul
Paul 4430
So did you try and fool's bi-amp, or did you really bi-amp with an electronic crossover?
With 37W/channel the Bel Canto Set 40 would be capable of driving the 107dB/W JBL 2344 horn in the 4430 monitor to well in excess of 125dB!
Even if you drove it through the passive JBL crossover bi-amp input and used a real electronic crossover it should have been able to play loud enough for you.
DJK:
If you have a 200W/channel amp it does not make sense to get a 2nd 200W/channel amp and bi-amp passively.
However, if you have a parallel crossover network, it can make perfect SENSE to "fools biamp", since you can use a high-damping factor brute amp for your low frequency section and a sweet sounding SET or Class A amp on the mids/highs. The only trick, of course, with two different amps is to be able to gain match.
So in a pro-sound mindset I'd say "fools biamp" is a viable term, but maybe not in audiophile terms.
I've done this sort of bi-amping using SET monoblocks to drive mids/tweets and a more robust amp to drive woofers with really nice results. What it did for me is cut down on how much current I was trying to pull through the 300B SET amps ultimately giving a higher level of overall output. I enjoyed the snappy, speedy and detailed sound of the 300B SETs on the mids/highs and the authoritative, well controlled bass from a brute of an amp on the lows.
I love the mids and highs of single 300B SET amps but the bass leaves a bit to be desired on some types of music. For me, this bi-amp method is a godsend.
Cheers,
Presto
Fools bi-amping is when you leave that horrid passive crossover in place.
You can achieve pretty much the same by just getting a single bigger amp.
The real and quite large difference happens when you use an active line-level xover.
Everything else is just pissing in the wind.
So if you remove a 6 or 10db l-pad from a highpass section and use a nice tube powered SET amp instead and use a high-damping factor brute amp on the lowpass (and attenuate to gain match) you're a fool for doing so?
I think it's brilliant!
I also think going "all active" is not necessarily better. There are active solutions that can be a step down from passive. I've heard them.
Cheers,
Presto
It is foolish as long as you leave the passive xovers series inductor in the circuit as it makes a complete mockery of the bass amps DF (read: control) and passives still produce around 3dB or more of insertion loss.
There is nothing stopping you from using any type of amp fully active and since active xovers usually have gain control it is a lot easier to match amps. No L-pads needed anywhere.
Also a good active xover is a fair bit cheaper than a passive using boutique components.
In my case the saving was easily enough to pay for the extra amp(s).
I am well aware of the benefits of active crossovers (and typically use them exclusively). But this is not a "from scratch" DIY effort. This is an existing passive design with a specific sound, and specific voicing. Even the impedance related 'errors' are part of the final voice of the speaker. Since the final sound is not really 'erroneous', then these errors are actually part of the equation.
Let's say you have 4th order LR (electric) passive crossovers. You replace them with 4th order active. Guess what, the sonics just changed because the impedance of each driver in the passive network was not perfectly flat, which interacted with the crossover impedance, resulting in a very specific transfer function. So when people speak of "fools biamping", one could argue just as fast that an arbitrary acoustic response from an 'active replacement' is also foolish, if the intent was to preserve the original sonics of the speaker in question.
You can get the added benefits of active, but the "changeout" is far far more complex than saying "Okay - replace LR2 passive with LR2 active, there, I fixed it."
If I could offer a customer identical acoustic response with a given crossover, I would consider calling the effort a "passive to active conversion". But if the sonics change, it's really a new speaker at that point and not an improved version of the original.
Building from scratch is a whole other kettle of fish.
Cheers,
Presto
It is however similar to me converting my Tannoys (Little Red Monitors) to active operation.
The original low pass was 12dB/oct electrical, while the tweeter was an odd combination of 6 and 12dB/oct which created the needed cd horn boost and also included a notch filter.
This was replaced by a very standard active L-R 24 and a parametric eq for the boost and notch.
The result still clearly sounds like a Tannoy pepperpot DC but with a remarkably cleaner, tighter bass and a slightly smoother treble. Obviously the tweeter needed de-inverting.
I also got them to within +-2dB over their entire range.
The one main difference is that without the passive xover between it and the amp the woofers power handling went down from 100w to 50w (the driver itself was clearly marked as such internally while the 100w figure came from the tech manual which states power handling as 125Wrms, 100Wrms for woofer and 25Wrms for the tweeter part).
A friend of mine activated his later 215DMT (officially the crossover is an 'overdamped second order low frequency, first order high frequency', same as mine really) and Tannoys own engineers recommended fourth order L-R but that was some time after I did mine.
I didn't bother asking Tannoy, I just went with my previous experiences of turning passives to active. Usually it is a good idea to use steeper slopes active than passive.
None of the advantages of active/multi-amping are being questioned though. What I am talking about is a couple assumptions that are being made when suggesting the active conversion is the way to go:
1. Guys like the OP are willing to do a passive to active conversion at all.
2. Guys like the OP have the skillset required. (i.e. +/- 2db).
Some people are fanatical about the voicing of their "brand name" speakers and they want the voicing that the original designed intended. Some guys claim they can hear +/- 0.1 db. Or +/- 0.5 db. (And some can't hear a reverse null... go figure).
The point is, I would not call a bi-amper a "fool" (fools bi-amping) if his intent was to use dedicated amps for low and highpass sections. In fact, I would call him ingenious if his high-pass amp was lower in gain (i.e. single-ended tube stuff) so he removed a simple L-pad out of the original circuit to compensate and not waste amp power on heating up resistors for a gain drop he no longer needs.
All that said, I think it's possible to do a passive to active conversion that is very close. With a DIY effort, BOTH final products are DIY, so there is no "carved in stone response". But with a "precious" high end design, the final response is a signature - once you muck with it, they're no longer "that speaker" but really just a speaker with all of the same physical parts, sans crossover.
SO! (gasp for air). Did you measure impulse response with your Tannoys?
I like the idea of concentrics very much, which is probably for many of the same reasons I became a MTM and WMTMW fan.
Cheers,
Presto
Hi Presto
I was reading your reply to DJK on the fools biamp and seems like you are doing exactly what I have been trying to do. Bi-amp a pr of horn speakers with a SET 845 on HF and a SS on the LF. I cannot think of a better sound for my taste, when this is working. You mention that the two amps need to have a match in gain. I am not terribly technical, but how do you measure these gains? Is it simply a standard measure in the amp specs? I really do believe in the 4430 JBL monitors and want to make them sound their best, and do so within financial reason. Any advice on this would be appreciated.
Paul
Paul 4430
Unfortunately, the 3134 crossover in the 4430 monitor does not appear to be "simply bi-wire/bi-ampable". You can select between single input to internal crossover networks, or this strange input that requires a "1khz crossover" in combination with portions of the internal crossover.
To biamp-these you will need whatever that "1khz external crossover" is, be it active or passive. I would ask around about these on the audioheritage.com website - search for 4430 or 3134. Sorry, but it's not a typical "remove the jumpers and bi-amp" situation and results in far more complexity than just gain matching.
Here are some links to get you started...
http://www.jblpro.com/pub/obsolete/443035.pdf
http://www.jblproservice.com/pdf/Network%20Schematics/3134%20Network.pdf
http://www.audioheritage.org/html/profiles/jbl/4430-35.htm
http://www.diyaudio.de/html/jbl_4430.html
Thank you very much Presto. You have given me alot to think on. I have gotten the feel that 4430 are not a simple task and that maybe they are better left untouched. I am going to follow your suggestions and see where they lead. In the meantime, thank you again for the advice.
Paul
Paul 4430
I have a 4430 speaker setup, with additional 15-inch subwoofers on each side, pretty much a 4435 setup. I have a Dynaco ST416-A, a Dynaco 400, and a Dynaco QSA-300 Quad amp (bridgeable). I have a JBL / Urei 5235 crossover, but am thinking of getting rid of that and getting a Nady CS-22XW crossover, which would give me Low and High outputs on each channel (1/4 unbalanced), and a summed subwoofer, that I could use to drive both 15-inch subs together in mono - perhaps with one of the Dynacos bridged into mono. The Nady has a 12db crossover slope, so if I bypassed the internal JBL crossovers, I'm thinking it could work well. Also have a dBx DriveRack and Digitech Quad-7 Equalizer, to provide front-end processing, as well as Ivie IE-30 Real Time Analyzer. Just want to have a really kick-ass studio monitoring system. Thoughts?
-t
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