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Old 03-23-2018, 06:17 AM
jonfields45 jonfields45 is offline
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Default NAD - Fishman Loudbox Mini Charge

It came yesterday and I put it through its paces with an SM58, MiSi Trio equipped RainSong Concert Hybrid Parlor and a K&K Mini equipped RainSong Concert Hybrid WS.

I guess the news is there is not much to report. It sounds fine with plenty of volume potential. Whether it is plugged into the 12 volt adapter, or not, seems to of no importance (given a charged battery). I think the reverbs are very good. I did not notice anything missing in its bass response, which was reported by one other AGFer and held up my purchase some as I thought about it.... However I only have a Yamaha DBR10 at home for comparison (and the DBR10 needs to be on a stand or in monitor position to sound as good as the Fishman).

I had previously contacted Fishman to confirm the battery type. It is a Sealed Lead Acid battery which on the plus side have a standard universal charging method and are plentiful for future replacement. Lighter Lithium Ion battery packs tend to be quite proprietary and it is hard to imagine a Fishman product at its low sales volumes relative to say a PC driving a market for third party replacements.

A very high resistive impedance load brings out some badness for the K&K and it was subtly there (a loss of high end sparkle and something not quite right in the low mids). I have a 500K input impedance MOSFET buffer pedal and also a 1M strapping resistor and both took care of that problem. Several respected AGF contributors do not take K&K's warning seriously, and a pure capacitive high impedance load (usually avoided by audio designers) should not cause any issue which will make some of the posted experiments not applicable, but I think with this amp a K&K should be buffered first for best tone -- at least for a RainSong CH-WS.

[For the technically inclined, each K&K head can be modeled as your signal in series with a capacitor. Like the pickups on a Strat, each head generates slightly different harmonic content that is not quite identical for amplitude and phase. If all three heads put out the same signal, then a one head pickup would sound as good as a three head version... Each head sees the other heads as a load for those harmonics which are not identical in amplitude and phase which causes some odd cancellations more apparent at higher frequencies where the difference between heads can be significant. A dominant time constant that makes those head loads look trivial compared to the amp input is the simple solution and that is why K&K specs a load in the 1M range. Too low a load, and then the series capacitance of each head becomes a pass band time constant and you loose bass response.]
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  #2  
Old 03-23-2018, 09:16 AM
lkingston lkingston is offline
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Default NAD - Fishman Loudbox Mini Charge

Quote:
Originally Posted by jonfields45 View Post
It came yesterday and I put it through its paces with an SM58, MiSi Trio equipped RainSong Concert Hybrid Parlor and a K&K Mini equipped RainSong Concert Hybrid WS.

I guess the news is there is not much to report. It sounds fine with plenty of volume potential. Whether it is plugged into the 12 volt adapter, or not, seems to of no importance (given a charged battery). I think the reverbs are very good. I did not notice anything missing in its bass response, which was reported by one other AGFer and held up my purchase some as I thought about it.... However I only have a Yamaha DBR10 at home for comparison (and the DBR10 needs to be on a stand or in monitor position to sound as good as the Fishman).

I had previously contacted Fishman to confirm the battery type. It is a Sealed Lead Acid battery which on the plus side have a standard universal charging method and are plentiful for future replacement. Lighter Lithium Ion battery packs tend to be quite proprietary and it is hard to imagine a Fishman product at its low sales volumes relative to say a PC driving a market for third party replacements.

A very high resistive impedance load brings out some badness for the K&K and it was subtly there (a loss of high end sparkle and something not quite right in the low mids). I have a 500K input impedance MOSFET buffer pedal and also a 1M strapping resistor and both took care of that problem. Several respected AGF contributors do not take K&K's warning seriously, and a pure capacitive high impedance load (usually avoided by audio designers) should not cause any issue which will make some of the posted experiments not applicable, but I think with this amp a K&K should be buffered first for best tone -- at least for a RainSong CH-WS.

[For the technically inclined, each K&K head can be modeled as your signal in series with a capacitor. Like the pickups on a Strat, each head generates slightly different harmonic content that is not quite identical for amplitude and phase. If all three heads put out the same signal, then a one head pickup would sound as good as a three head version... Each head sees the other heads as a load for those harmonics which are not identical in amplitude and phase which causes some odd cancellations more apparent at higher frequencies where the difference between heads can be significant. A dominant time constant that makes those head loads look trivial compared to the amp input is the simple solution and that is why K&K specs a load in the 1M range. Too low a load, and then the series capacitance of each head becomes a pass band time constant and you loose bass response.]


The two main disadvantages of a SLA battery are longer charge times and gradually diminishing power as the battery discharges. A lithium battery is going to charge far more quickly and give you full wattage until it suddenly dies. Of course it’s going to be way more expensive when it needs to be replaced.
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Old 03-23-2018, 02:22 PM
lkingston lkingston is offline
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The other day one of my friends met me at an outdoor tennis court. We wanted to see how his Fishman LB mini Charge and my Bose S1 would do competing against each other in a moderate sized outdoor venue. Volume and sound quality wise, they were very close, though we both agreed that the S1 has a slight edge. He does a lot of drop tunings and you could really hear the difference on the low notes.

Neither is really up to covering much space outdoors.

We were out there quite a while and you can hear the sealed lead acid battery drop a bit of output power over time.

Interestingly, we both liked the S1 tonematch mic preset better than the guitar preset or no preset on his guitar.
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Old 03-25-2018, 12:09 PM
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Thanks for the review. I have been looking at one of these for strictly home use. I was wondering how long was it out there on the tennis court before you noticed the decrease in power?
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Old 03-31-2018, 09:39 AM
jonfields45 jonfields45 is offline
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I was in GC this morning and I noticed that the Loud Box Mini Charge has a much heavier duty more deeply textured vinyl compared the Loud Box Mini (at least for what was on display). I know that fragile vinyl has been a long time criticism of the Mini and it appears to have been fixed for the Charge.
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Old 05-19-2018, 04:38 PM
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Any updates on the Charge? How is it working out?

I may pick one up and also an S1 Pro ..and return the loser in the shootout.
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Old 05-19-2018, 11:21 PM
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Any updates on the Charge? How is it working out?

I may pick one up and also an S1 Pro ..and return whichever is the loser in the shootout.
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Old 05-20-2018, 07:39 AM
jonfields45 jonfields45 is offline
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Quote:
Originally Posted by Groberts View Post
Any updates on the Charge? How is it working out?

I may pick one up and also an S1 Pro ..and return whichever is the loser in the shootout.
No issues to report. It is a nicely powerful little amp. I've tested it as a PA for my duo using an XLR Y-cable for two SM58s and a simple resistor mixer (two 50K ohm resistors) for two active guitars. Sitting on the ground I find myself cutting back the bass a bit on the guitar(s). Up on a chair or table, flat works fine. I like that the AUX input on the back goes to the master volume. I've tried using it with an active guitar (3.5mm TRS male to 1/4" Female TS adapter -- the 25K ohm input impedance is too low for a K&K) and that works well too. Maybe the guitar preamp has a bit of bass boost that the mic and aux inputs do not.

I leave it on its charger in my music room and when my duo practices it has become the bass amp (I leave the DBR-10 in a closet by the garage these days along with the rest of my PA gear). I'm also using it as an electric guitar amp, though lately with a Behringer GDI21 for a touch of distortion. In both applications it works really well at practice room volumes.

The internal battery must be a fairly low self discharge SLA since leaving it unplugged during my last trip out of town (5 days) resulted in the charge light only coming on for a few seconds when I returned.
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Last edited by jonfields45; 05-20-2018 at 07:46 AM.
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Old 05-22-2018, 12:21 PM
lkingston lkingston is offline
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Quote:
Originally Posted by jonfields45 View Post
No issues to report. It is a nicely powerful little amp. I've tested it as a PA for my duo using an XLR Y-cable for two SM58s and a simple resistor mixer (two 50K ohm resistors) for two active guitars. Sitting on the ground I find myself cutting back the bass a bit on the guitar(s). Up on a chair or table, flat works fine. I like that the AUX input on the back goes to the master volume. I've tried using it with an active guitar (3.5mm TRS male to 1/4" Female TS adapter -- the 25K ohm input impedance is too low for a K&K) and that works well too. Maybe the guitar preamp has a bit of bass boost that the mic and aux inputs do not.

I leave it on its charger in my music room and when my duo practices it has become the bass amp (I leave the DBR-10 in a closet by the garage these days along with the rest of my PA gear). I'm also using it as an electric guitar amp, though lately with a Behringer GDI21 for a touch of distortion. In both applications it works really well at practice room volumes.

The internal battery must be a fairly low self discharge SLA since leaving it unplugged during my last trip out of town (5 days) resulted in the charge light only coming on for a few seconds when I returned.

You could also use one of these, although it is expensive for what it is:

http://avlifesavers.com/xlrmix.htm
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Old 05-22-2018, 10:18 PM
Riles Riles is offline
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lkingston—XLR mixer seems like a great solution to use for guitar and 3 vocal mics (which is my typical set up) for smaller PA systems like S1 Pro or L1c or similar. Have you used this before? Thanks for advice
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Old 05-23-2018, 08:43 AM
lkingston lkingston is offline
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Quote:
Originally Posted by Riles View Post
lkingston—XLR mixer seems like a great solution to use for guitar and 3 vocal mics (which is my typical set up) for smaller PA systems like S1 Pro or L1c or similar. Have you used this before? Thanks for advice


I have one. You do lose a little gain, but if you have a higher output dynamic like a beta 58 it isn’t bad. I don’t use it regularly but it can be handy from time to time.

Keep in mind that it is about the same price as a Behringer Xenyx 1002B which is a full featured battery powered mixer which is definitely more bang for the buck.

My regular gigging format is one guitar and at least two vocals so I know where you are coming from.
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Old 05-23-2018, 10:05 AM
sublro sublro is offline
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Quote:
Originally Posted by jonfields45 View Post

[For the technically inclined, each K&K head can be modeled as your signal in series with a capacitor. Like the pickups on a Strat, each head generates slightly different harmonic content that is not quite identical for amplitude and phase. If all three heads put out the same signal, then a one head pickup would sound as good as a three head version... Each head sees the other heads as a load for those harmonics which are not identical in amplitude and phase which causes some odd cancellations more apparent at higher frequencies where the difference between heads can be significant. A dominant time constant that makes those head loads look trivial compared to the amp input is the simple solution and that is why K&K specs a load in the 1M range. Too low a load, and then the series capacitance of each head becomes a pass band time constant and you loose bass response.]
hey jon - so are you saying here that a 470kohm impedence would be a bad thing with the K&K? i'm thinking of using an EQ pedal with 470kohm as the first thing on my signal chain, as my preamp is a 10megohm impedence, but if i understand you right here, you're saying that less than 1mohm according to K&k could also be problematic? (i.e. reducing bass? how much? consequential? the reason I wanted to use the MXR is that it's 18 volt and so has (i think) additional headroom to help with spikes that the K&K can put out when playing percussively and "hitting" the bridge right over the pickup's elements....
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Old 05-23-2018, 10:18 AM
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FYI. Thread derail aside, I ordered the Fishman Loudbox Mini Charge and it should be here this Friday! Comes with the really nice heavy duty carry bag for free until then end of May2018. ($99 value bag tha I would have wanted anyway)

I will be sure to record a new demo in my small office/music room.
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Old 05-23-2018, 11:25 AM
AeroUSA AeroUSA is offline
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Quote:
Originally Posted by sublro View Post
hey jon - so are you saying here that a 470kohm impedence would be a bad thing with the K&K? i'm thinking of using an EQ pedal with 470kohm as the first thing on my signal chain, as my preamp is a 10megohm impedence, but if i understand you right here, you're saying that less than 1mohm according to K&k could also be problematic? (i.e. reducing bass? how much? consequential? the reason I wanted to use the MXR is that it's 18 volt and so has (i think) additional headroom to help with spikes that the K&K can put out when playing percussively and "hitting" the bridge right over the pickup's elements....
Losing extra bass on a K&K could be a good thing. 500-1kohm is fine.
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Old 05-23-2018, 11:29 AM
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Losing extra bass on a K&K could be a good thing. 500-1kohm is fine.
thanks - yeah, enough bass is not a worry with k&k :-)
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