[martycat]

Just feel curious whether the different kinds of batteries affect the performance of SR-71? I've got some different batteries, alkaline / non alkaline (the old type of battery... dunno what I should call it.

) / rechargeable NiMH at 8.4V and "stated 9V"...
The amp is still running on 2 "old type batteries" and I dunno when they will be flatted. The red led goes dimmer now but it's still working. I tried 2 8.4V NiMH for a while before but didn't notice big difference. So should I bother with the battery issue? Thanks!

 

[raisin]

Regular disposable alkaline battery's provide 50+ hours of play time, and will keep the red LED burning much longer than that. From what I understand, rechargable battery's don't last quite as long.

 

[martycat]

Thanks! So besides of the battery life, is there any difference sound wise?

 

[john_jcb]

Quote:

Originally Posted by martycat Thanks! So besides of the battery life, is there any difference sound wise?

None that I have read about.

 

[Lisa]

Try new alkalines and compare them to half depleted 8.4v nimh. If there isn't a noticable difference your rechargeables will be fine.

Alkalines drop their voltage graduately. Which can cause a decrease in soundquality while they deplete.
Rechargables stay at the same voltage untill just before they're empty. So the soundqaulity should remain the same.

Therefor fresh 9V alkalines can sound better than half depleted ones while Nimh will not loose soundquality. It depends on the amp if this is an issue or not.
If it isn't an issue it doesn't matter what you use. If it is, it could be that fresh alkalines sound better than Nimh, but they will loose quality gradualy while they deplete. So then it's up to you what you prefer. Good at first, slowly getting worse while the batteries deplete(alkalines) or same quality all the time. Less then fresh alkalines, better than (more than) half depleted alkalines (nimh 8.4V) (I don't exactly know when the point is when using alkalines where they both give out the same voltage.)

You can always go for Plainview or MAHA 9V NiMH batteries if you want good sound and rechargables since they are 9.6V.

 

[martycat]

Thanks all! Then I think I'll stick with the NiMH... as it sounds a big waste to dispose the half drained alkalines. Well... I just have the SR-71 takes 9V in my entire house.

Yea I'm interested in the Plainview but I can't justify the shipping charge for some little batteries to my homeland.

 

[Lisa]

You don't know for sure if the SR-71 suffers from soundquality loss when the batteries are more than half depleted.
If I were you I would just get a pair of alkalines and try to see if you hear a difference between the nimh and fresh alkalines. then after 10 hours of use. 20 hours etc. and then make up your mind which betteries suit your needs best.

 

[Ray Samuels]

Lisa....
I do not agree with what you mentioned regarding the Alkaline being best when they are fresh & quality of sound drops when they are down in voltage, may be in different components, but let me state this clearly that the Emmeline SR-71 works the same way & with the same quality of sound when the Alkaline are new at 9VDC all the way down to less than 3.5VDC with out dropping the quality of sound or reduction of volume at all. when it stops playing, that is the only time you would think to change the battery. The LED stays on a little longer then it goes off.
Ray Samuels


Quote:

Originally Posted by Lisa Try new alkalines and compare them to half depleted 8.4v nimh. If there isn't a noticable difference your rechargeables will be fine. Alkalines drop their voltage graduately. Which can cause a decrease in soundquality while they deplete. Rechargables stay at the same voltage untill just before they're empty. So the soundqaulity should remain the same. Therefor fresh 9V alkalines can sound better than half depleted ones while Nimh will not loose soundquality. It depends on the amp if this is an issue or not. If it isn't an issue it doesn't matter what you use. If it is, it could be that fresh alkalines sound better than Nimh, but they will loose quality gradualy while they deplete. So then it's up to you what you prefer. Good at first, slowly getting worse while the batteries deplete(alkalines) or same quality all the time. Less then fresh alkalines, better than (more than) half depleted alkalines (nimh 8.4V) (I don't exactly know when the point is when using alkalines where they both give out the same voltage.) You can always go for Plainview or MAHA 9V NiMH batteries if you want good sound and rechargables since they are 9.6V.

 

[photographlondon]

I've been wondering about this myself, having used both Nimh and alkalines in my SR-71 it's good to hear that either is fine from the horses mouth, thanks for posting this info Ray

 

[martycat]

Lisa, maybe I have woody ears... I don't notice difference thru the life span of the same pair of battery. The amp seems to work the same... then suddenly it doesn't sing anymore with a dim red led.

Indeed I haven't tried any alkaline yet, I had finished a pair of "non-alkaline" and now it's running on 2 NiMH. I still can't notice any difference... I guess I need some more ear training~

Thanks for your advice!
Ray, I like the amp very much! My living place is very very small and it doubles as my home / portable amp. Thanks!

BTW, which type of battery do you recommend? Certainly I prefer the rechargeable for long term. But does the voltage really matter? I have 2 pairs of batteries and 2 of them are 8.4V, the other 2 are stated as "9V"...
Thanks!

 

[Ray Samuels]

Hi martycat...
I have never owned or used any rechargeable battery, that I can't help you with, as to voltage of the two rechargeable batteries you mentioned, it won't make the difference. I use only the copper top battery, after almost 60+ hours on the last set, the sound stoped. I do not know how many hours are the rechargeable capable of giving as it depends on how well they hold the charge & if they have that many cycles of life or even shelf life, it may also depends on the charger used.
Thanks.
Ray Samuels

Quote:

Originally Posted by martycat Lisa, maybe I have woody ears... I don't notice difference thru the life span of the same pair of battery. The amp seems to work the same... then suddenly it doesn't sing anymore with a dim red led. Indeed I haven't tried any alkaline yet, I had finished a pair of "non-alkaline" and now it's running on 2 NiMH. I still can't notice any difference... I guess I need some more ear training~ Thanks for your advice! Ray, I like the amp very much! My living place is very very small and it doubles as my home / portable amp. Thanks! BTW, which type of battery do you recommend? Certainly I prefer the rechargeable for long term. But does the voltage really matter? I have 2 pairs of batteries and 2 of them are 8.4V, the other 2 are stated as "9V"... Thanks!

 

[Flea Bag]

Does anyone here know if those 'Eveready' Heavy Duties or cheap industrial battery brands behave voltage wise? Do alkline voltages drop more severely than the above-mentioned ones?

 

[martycat]

Thanks Ray to make it clear! Great, I'll stick with the rechargeables.

 

[PATB]

Thanks for posting Ray.

I am also interested in this topic because I use my SR-71 with my iPod, dedicated source, etc. Right now, it is connected to the line out of my Sony VAIO laptop to drive my Grado SR-225. The amp is quite portable and handy so I always use it. Thank goodness the battery life is good enough that I don't have to worry about buying lots of batteries (I don't use rechargeables either).

 

[Lisa]

Quote:

Originally Posted by Ray Samuels Lisa.... I do not agree with what you mentioned regarding the Alkaline being best when they are fresh & quality of sound drops when they are down in voltage, may be in different components, but let me state this clearly that the Emmeline SR-71 works the same way & with the same quality of sound when the Alkaline are new at 9VDC all the way down to less than 3.5VDC with out dropping the quality of sound or reduction of volume at all. when it stops playing, that is the only time you would think to change the battery. The LED stays on a little longer then it goes off. Ray Samuels

Ray,
I haven't heard the SR-71 so that's why I mentioned that it depends on the amp and stated that alkalines CAN (not will) decrease the soundquality when they are further depleted. I'm sorry if I wasn't clear enough.
I notice this in my MINT amp which runs on a single 9V battery.
It is great to know though that the SR-71 doesn't suffer from this and even better that one can use 8.4V rechargables. Because you can't get those 9.6Vs here in Europe.