realistic scr-8

[monchito]

ok after a battle of trying to clean up i saw my scr-8 and remembered it was in need of a speaker so i just grabbed it and did a quick fix but the speaker that was supposed to replace this was in bad shape also so i looked around and remembered that i had some speakers from a old lasonic so here is what it looks like now

 

[monchito]

here is another one plus it needs a little work still plus the led board need some attention to but over all i was amazed how well it sounded its very bassy

 

[BMoney]

now that's a nice mod/fix!
great job monchito!

 

[monchito]

it makes it look alot better with those speakers

 

[redbenjoe]

now that's a nice mod/fix!
great job monchito!

super idea to use those speakers-
and with those big caps and the light color --
they look MUCH better than the originals

 

[eldorado]

nice box. looking good.

me like.

 

[monchito]

now that's a nice mod/fix!
great job monchito!

super idea to use those speakers-
and with those big caps and the light color --
they look MUCH better than the originals

i knew you would like it ira it does make it look the way they should have done it when they first came out

 

[oldskool69]

Not a bad swap! Probably sounds more like it's twin the G.E. 5239-A Blockbuster. I had an SCR-8 before I dump...I mean sent it to Ira.

The SCR-8 didn't hit ashard as the BB.

 

[Superduper]

Hmm, I never thought about that but it sounds entirely plausible. Supposedly, they are the same but I imagine there are some differences and choice of speakers might be different as well. Ramon -- how much room is available in there for larger speakers? Do you think replacements with larger magnets and deeper body will fit? Anything in the back blocking the speakers?

 

[monchito]

Hmm, I never thought about that but it sounds entirely plausible. Supposedly, they are the same but I imagine there are some differences and choice of speakers might be different as well. Ramon -- how much room is available in there for larger speakers? Do you think replacements with larger magnets and deeper body will fit? Anything in the back blocking the speakers?

not reall only the tranformer but i belive a bigger mag might work as long its the same in depth wise the right hand side has all the room to spare plus the box uses the typical toshiba layout where the electronics are at the top

 

[monchito]

ok norm here is a pic of the inside

 

[Superduper]

Thanks Ramon. Doesn't look like that much toom to me. Most decent aftermarket speakers have huge magnets. Also, most are deeper too. Still worth looking into though. When I have time..... got so much going on right now.

 

[monchito]

ok norm i was really going to put the speakers from a m70 but it turned out to be 8ohms instead of 4 so i know it might work but i think i will lose something in the process

 

[oldskool69]

ok norm i was really going to put the speakers from a m70 but it turned out to be 8ohms instead of 4 so i know it might work but i think i will lose something in the process

You are correct. You will lose volume and the amp will have to work harder to push current.

 

[monchito]

yea that why i did not go that route anyway with the lasonic speakers it sounds a lot better i still want to go againts the bb so i will have a chance with iras

 

[Superduper]

ok norm i was really going to put the speakers from a m70 but it turned out to be 8ohms instead of 4 so i know it might work but i think i will lose something in the process

You are correct. You will lose volume and the amp will have to work harder to push current.

I'd tend to disagree. Lower impedance is where you can strain an amp because it will push more current, working it harder, possibly blowing the amp if impedance gets too low. Higher impedance means less current will get pushed so it'll be more like cruising along, albeit at lower volume and output. However, since the amp is currently struggling at higher output levels anyhow, it might not be a bad compromise to try to cut the output a bit. In fact, most amps caution agains too low impedance. No such caution exists, far as I know, for too high impedance. You just won't get much power output if impedance is too high. That's just my opinion, FWIW.

 

[monchito]

norm thats what i thought to the lower the more it stuggles but i may try to install them just to try them out since the box has very good deep bass i will try that and give a report to what i find

 

[oldskool69]

Maybe I misunderstood and thought he was using an 8ohm speaker.

If that were the case I'm correct in that the current flow would be restricted further, thus decreasing volume, requiring more work out of the entire circuit to get original levels of loudness and Norm is is right because the amp chip itself will cruise as it does not have to keep up with excessive current flow. Now, if you are using a 4ohm speaker, then you will have greater current flow easing the strain on the circuit itself and the amp chip will have to work harder to keep up with it or fry in the process.

I haven't cracked open my Blockbuster since last year so Icouldn't tell you what the original load for the factory setup is on the speakers. Did it say it on the SCR-8?

 

[Superduper]

What I noticed about the SCR-8 is that at up to about 5/8 to 2/3 volume, it sound great. Good power output. More than that and there is noticeable distortion. Nobody in their right mind would operate it like that since it sounds like it wants to blow up. The speakers could be contributing to it but I'm thinking that the amp doesn't like being at that power output level.

So, if Ramon were to install the M70 speakers, which is 8 ohms, instead of 4, then at full volume, the amp may be perfectly happy. It may not be as loud as if it were a 4 ohm speaker but since you could only get 1/2 or 2/3 volume anyhow (the rest is wasted) with the 4 ohm speakers, then maybe you can get full range on the volume control with the 8 ohm speakers instead. Just a hypothesis. Let's see if Ramon follows through and reports on this experiment.

 

[oldskool69]

Exactly. I experiment as well with speaker setups as most boombox amps can easily be driven into clipping at which point the sound like crap even f the speakers can take more. I have a lot of heavy hitter type boxes ao I get a kick out of seeing how far I can drive my lesser ones.

One factor we did not mention however is efficiency. (Better known as sensitivity.) A great example of this is my Sansui SP-5500X speakers (very sensitive) which at 1w can deliver 98dB SPL. Now that's efficient! But let's be realistic. To find that to work in a boombox...would be like finding the holy grail.